New York
Generalized Bedrock Geology of NY
INCOMPLETE WORKING VERSION OF FILE NEPALEO.T2T
In previous terrane discussions, I have stuck to areas that geologists recognize as "terranes", but now we have come to the biggie for North Americans -- the rocks at the core of the North American continent. The area involved is very large. As is the number of formations and groups. Fortunately, it can be subdivided reasonably easily into Eastern and Western parts separated by a wide belt of Cretaceous and Tertiary rocks in the Great Plains that separates the two halves. Even more conveniently, in the Eastern part there is a long period of non-depositation that includes -- with a handful of isolated exceptions -- just about everything later than the Permian.
Therefore, this "East Laurentian Terrane" includes all the Paleozoic rocks East of the Rocky Mountains except those of the Black Hills, and except the Permian (and Triassic) beds of West Texas and adjacent Oklahoma. It excludes the beds in the various Terranes associated with the opening and closing of the Iapetus Sea. They are addressed in other Terrane discussions. But it does include the "Humber Zone" of Newfoundland and Quebec as well as the Paleozoic rocks of Western Manitoba, Central Oklahoma, and Central Texas. The Black Hills and West Texas Permian will be discussed in the Western Section.
The pattern of depositation in the Eastern Laurentian Paleozoic is remarkably consistent considering the size of the area. After a long period of non-depositation in the Ediacaran and most of the Lower Cambrian, marine sandstones appear in the Middle Cambrian. As time passed, the sandstones/siltstones/quartzites became more calcaerous. Limestones, and especially, dolomites became the dominant rocks in the latest Cambrian and Early Ordovician. As time passed, the dolomites transitioned to purer limestones -- often abundantly fossiliferous -- in the Middle Ordovician. In the upper Ordovician, the limestones were replaced with black shales in the East and alternating shales and thin limestones further West. The Silurian was time of diverse depositation -- continental beds, shallow water marine deposits, evaporties, and deeper water deposits are mixed. By the Middle Devonian, fossiliferous shales, clays and thin limestones were widespread. As the Devonian passed, beds became shallower, more acidic (fossils are molds rather than shells) and are interbedded with thick black organic shales. In the Mississippian, beds became mostly continental in the East while cyclic deposits of marine limestone, shales, sandstones and continental beds appeared in the West. As the Mississippian progressed, the marine beds became thinner and less frequent and coal beds started to appear in the cyclic deposits. The marine beds dissappeared entirely during the Pennsylvanian. Finally, Permian continental beds top the Paleozoic deposits in a few areas.
Several different (overlapping) naming schemes have been used starting in the 19th Century. For example, the Upper Devonian rocks of New York have conventional Group/Formation/Member names, but they are also been grouped East to West into Catskill (non-marine), Chemung (shallow water marine), and Portage(/Naples) (deep water marine) facies. Early Geologists and Paleontologists were often prone to apply the nomenclature of the very fossiliferous and accessible Paleozoic beds of New York to beds of similar age in other regions. Much, but not all, of that work has been erased by subsequent workers.
This is bookkeeping stuff for my use and edification-DJK. It looks like this page will eventually include all of the Laurentian Paleozoic formations East of the Mississippi and some west into the Eastern plains, so the list of missing formations will be here for a while.
Missing Formations:
Fossils:
| thick | age | rocks | where | underlaying | overlying | equivalents | fossils: | [GEOLEX link | NO cgkn link | group |
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| 152m | Pennsylvanian,Upper | sandstone,shale,coal,limestone | MD,PA,WV | Glenshaw | Pittsburg Coal | fossils:? | GEOLEX link | NO cgkn link | Conemaugh Group |
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| ? | Pennsylvanian,Upper | limestone,shale,siltstone,coal | OH,PA,WV | Allegheny | Casselman | equivalents | fossils:marine invertebrates | GEOLEX link | NO cgkn link | Conemaugh Group |
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| 30 | Pennsylvanian,Lower | sandstone,conglomerate,coal? | MD,OH,PA | Connoquenessing | Olean | fossils: | GEOLEX link | NO cgkn link | Pottsville |
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| 120m | Ordovician,Middle | Sandstone,shale,limestone | OK(s),TX(w) | McLish | Criner,Bromide | equivalents | fossils:marine invertebrates | GEOLEX link | NO cgkn link | Simpson |
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| 2m | Pennsylvanian,Middle | limestone,shale | VA,WV | underlaying | Powellton | Breathitt | fossils:marine invertebrates(uncommon) | GEOLEX link | NO cgkn link | Kanawha,Wise |
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| 486m | Ordovician,Lower | limestones | OK(s) | Cool Creek | West Spring Creek | Alden | fossils:? | GEOLEX link | NO cgkn link | Arbuckle |
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| 486m? | Ordovician | limestones | OK(s) | Cool Creek | West Spring Creek | Kindblade | fossils:? | GEOLEX link | NO cgkn link | Arbuckle |
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| thick | age | rocks | where | underlaying | overlying | equivalents | fossils: | [GEOLEX link | NO cgkn link | group |
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| thick | age | rocks | where | underlaying | overlying | equivalents | fossils: | [GEOLEX link | NO cgkn link | group |
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| thick | age | rocks | where | underlaying | overlying | equivalents | fossils: | [GEOLEX link | NO cgkn link | group |
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| thick | age | rocks | where | underlaying | overlying | equivalents | fossils: | [GEOLEX link | NO cgkn link | group |
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| thick | age | rocks | where | underlaying | overlying | equivalents | fossils: | [GEOLEX link | NO cgkn link | group |
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NEW YORK (AND WESTERN VERMONT) FORMATIONS
NOTE The key to the New York State Geologic Map shows the relationships of most of these formations much more clearly than I can do in a text only presentation.
Typically 30 meters but up to 50 meters of sandy dolomite and dolomitic Middle Ordovician sandstone found in Arkansas,Missouri and Illinois. It overlies the Jefferson City Dolomite/Dutchtown Dolomite/Crystal City Sandstone and is overlain by Augusta Formation. It is the oldest member of the Joachim Dolomite
Fossils: None? Possibly a few bivalves?
Up to 30 meters of Pennsylvanian shales and limestones found in Iowa, Kansas, Nebraska, and Oklahoma. Overlies the Emporia Shale/Wabaunsee Group and is overlain by the Americus Limestone/Council Grove Limestone. It includes the Aspinwall Limestone, Brownville Limesone, Falls City Limestone, Five Point Limestone, Hamlin Shale, Hawxby Shale, Janesville Shale, Onaga Shale, Towle Shale, and West Branch Shale. Treated as a group by some authors and as a member of the Vanoss Group by others
Fossils: fusilinids and brachiopods
100 meters of Lower Ordovician dolomite with minor shale and limestone found in the Southwest Arm area of Newfoundland. It overlies the Catoche and is overlain by the Table Head Group. It is the uppermost member of the St George Group
Fossils: conodonts. ichnofossils?
3 to 5 meters of Uppermost Silurian Dolomite found in Western New York (and adjacent Ontario?) where it overlies Bertie Formation carbonates and is overlain by Lower Devonian formations
Fossils: TBPL
An obsolete term for sandstone units at the base of the Lower Silurian Medina Group including the Whirlpool Sandstone, Grimsby Sandstone, and Thorold Sandstone and associated units. Abandoned because it was unclear exactly what units were involved. It overlies the Ordovician Queenston Shale and is overlain by the remainder of the Silurian units in the area. It is found in the Niagara region of New York and Ontario.
Fossils: Unknown
Upt to 60 meters of Middle Silurian "shale" (clay) with minor limestone and dolomite found in east central Kentucky and adjacent Ohio. It overlies the *Indian Fields Formation*/Drowning Creek and is overlain by Devonian rocks Includes the [Lulbegrud Clay *Lulbegrud], [Waco Limestone *Waco], [Estill Clay *Estill]/ or [Lulbegrud Clay *Lulbegrud],[Flades Clay *Flades] or Osgood Formation,Laurel Formation,Missie Formation The Alger is sometimes considered to be a member of the Crab Orchard Formation
Fossils: Some brachiopods, corals, bryozoa, trilobites in the limestone/dolomite beds.
| 99m | Pennsylvanian,Middle | shale,sandstone,clay,coal,limestone | MD,OH,PA,VA,WV | Pottsville | Conemaugh | Breathitt | fossils:marine invertebrates | [GEOLEX link https://ngmdb.usgs.gov/Geolex/Units/Allegheny_53.html | NO cgkn link | Allegheny Group |
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Ten to thirty meters (depending on the author) of fossiliferous Middle Devonian limestone found in East Central Michigan. It overlies the Genshaw Formation and is overlain by the Dock Street Clay/Four Mile Dam Limestone. The nomenclature is confused and confusing. The Alpena is a member of the Traverse Group
Fossils: Crinoids,Corals,Stromatoporoids,fish fragments,others?
8 to 17 meters of cherty, fossiliferous Lower Devonian limestone that overlies the Becraft formation in East Central New York and are overlain by Port Ewen beds. It is considered to be part of the Helderberg Group. Fossils: TBPL
Up to 260 meters of Lower Pennsylvanian coal, shale, siltstone and sandstone found in Kentucky, Virginia and West Virginia. It overlies the Upper Seaboard Coal/Sewanee Sandstone and is overlain by the Beaver Creek Coal. It is a member of the Breathitt Formation
Fossils: Marine invertebrates, ichnofossils
Two fairly thin limestones bracketing a shale--perhaps 3 meters total. Upper Pennsylvanian and Lower Permian limestonesfound in Oklahoma(ne), Nebraska(s) and Kansas(e). It overlies the Emporia Shale and is overlain by the Dunlap Limestone/Elmdale Formation. It is a member of the Council Grove Group/Vanoss Group
Fossils: abundant fusilinids, crinoid stems, brachiopods
10 meters of Middle Devonian Dolomite exposed in Ontario opposite Detroit. Most Authors include the overlying Sylvania Sandstone in the Amherstburg. Soemtimes regarded as being equivalent to the Lucas Dolomite The Amherstburg is a member of the Detroit River Group.
Fossils: Present
Fossiliferous Black River age Middle Ordovician limestones found in isolated outcrops South and East of the Adirondack Mountains in New York. It is probably the uppermost portion of the Black River in areas where it outcrops.
Fossils: Fairly abundant and diverse marine fossils-Brachiopods,Bryozoa,etc
Fossiliferous Middle Devonian limestone found in SouthEastern Michigan, adjacent Ontario and NorthWestern Ohio. It overlies the Flat Rock dolomite and is overlain by the Amherstburg dolomite/Lucas dolomite
Fossils: Abundant coral-stromatoporoid reef fossils
10 to 15 meters of Middle Devonian siltstone with minor limestone found in East Central New York where it overlies the Calisle Center Formation and is overlain by the Saugerties Formation It is a member of the Schoharie Formation.
Fossils: probably present. Unclear how abundant or diverse
70 meters or more of Upper Devonian marine gray mudstones found in large parts of the Applachian Basin between the Rhinestreet Black Shale below and the Dunkirk Black Shale/Pipe Creek Conglomerate/Hanover Shale above. It is an element of the Portage facies. It is a member of the West Falls Group.
Fossils: Uncommon. Some plants. A few marine fossils.
80-100 meters of Lower Cambrian sandstone/quartzite found in Maryland,Pennsylvania,Virginia and West Virginia. It overlies the Harpers Ferry Formation and is overlain by the Tomstown Dolomite/Frederick Limestone. It is a member of the Chilhowee Group
Fossils: Ichnofossils. Trilobites, brachiopods, hyolithids in the upper beds.
A widespread unit of dark Upper Devonian/Lower Mississippian marine shale found in many areas of Michigan, as well as Northwest Ohio, Northern Indiana, Northern Illinois and Wisconsin. It overlies the Milwaukee Formation/Squaw Bay Formation and is overlain by the Ellsworth Shale or recent glacial debris.
Fossils: sparse marine invertebrates, pollen spores, conodonts
300 meters or more of colorful Lower Cambrian shales and minor limestone found in Tennessee,North Carolina and Georgia. It is the oldest formation exposed in its region and underlies sandstones of the Rome Formation/Hesse Sandstone It is a member of the Rome Formation
Fossils:
Up to 1800 meters of Upper Cambrian and Ordovician Limestones and Dolomites found in Missouri and Oklahoma. The Arbuckle overlies the Reagan Sandstone and is overlain by the Simpson Group. The Arbuckle is treated as a Group including the Butterly Dolomite, Chapman Ranch Formation, Cool Creek Formation, Cotter Dolomite, Eminence Dolomite Fort Sill Limestone (OK*), Gasconade Dolomite, Jefferson City Dolomite, Kindblade Formation, McKenzie Hill Limestone, Potosi Dolomite, Powell Dolomite, Roubidoux Dolomite, Royer Marble, Signal Mountain Limestone, Strange Formation, Van Buren Formation, West Spring Creek.
Fossils: Marine invertebrates
An obsolete term applied to several beds of fossiliferous Mississippian Limestone found in Arkansas, Missouri, Oklahoma, and Illinois totaling as much as 120 meters. The Archimedes rocks overlie the St Louis Limestone and are assigned nowadays to the Palestine Sandstone, St Genevieve Limestone, Warsaw Limestone and Keokuk Limestone in Illinois and Missouri. They are assigned to the Pitkin Limestone in Arkansas and Oklahoma.
Fossils: Abundant marine invertebrates -- bryozoa-Archimedes
up to 20 meters of fossiliferous Upper Ordovician shale,clay and limestone found in Southwest Ohio, Indiana, Kentucky and Tennessee. Different lithologies dominate at various locations. The Arnheim overlies the Leipers Limestone/Mt Auburn Shale/McMillan Formation/Hermitage Formation/Grant Lake Limestone. It is overlain by the Waynesville Shale/Sequatchie formation/Fernvale limestone. It is the oldest member of the Richmond Group and is sometimes subdivided into the Sunset Formation and the Oregonia Formation.
Fossils: Marine invertebrates are common, well preserved, and abundant.
Up to 43 meters gray-green Upper Ordovician mudstone with minor limestone found in South Central Kentucky. The Ashlock overlies the Calloway Creek Formation and is overlain by theGrant Lake Formation/Drakes Formation. It is laterally equivalent to the Fairview Limestone/Arnheim Formation/McMillan Formation. It is divided into six members:Tate Formation,Gilbert Formation,Stingy Creek Formation,Terrill Formation, Sunset Formation,Reba Formation
Fossils: The limestones in the Ashlock have abundant,diverse fossils. The other units have few or no fossils.
Several hundred meters of Middle Devonian non-marine Hamilton age shales and sandstones found in the Northern part of the Catskill Mountains of New York. It overlies similar marine beds of the Plattekill Formation It is overlain by Upper Devonian Oneonta beds.
Fossils: plants?
30 to 60cm of fossiliferous Lower Permian limestone found in Nebraska(se),Kansas(e),and Oklahoma. It is the lowest limestone in the Admire Group and the middle member of the Onaga Shale. It overlies the Towle Shale and underlies the Hawxby shale
Fossils: pelecypods, crinoids, brachiopods.
About 8 meters of calcaerous Pennsylvanian shale with limestone beds found in Oklahoma, Kansas(e) and Nebraska(se) The included limestones are called the Aspinwall Limestone It overlies the Brownville Limestone and is overlain by the Falls City Limestone. It is a member of the Admire Shale/Wabaunsee Group
Fossils: crinoid fragments, diverse brachiopods, others?
Up to 3000 meters of often calcerous Middle Ordovician marine shale found in Alabama, Georgia, Tennessee, and Virginia. It overlies the Chickamauga Limestone/Whitesburg Limestone/Lenoir Limestone/Newala limestone It is overlain by the Rockwood Formation/Ottosee limestone/Chambersburg limestone/Moccasin formation/Chota formation. In part it is equivalent to the Chickamauga Limestone/Paperville formation/Rich Valley formation/Edinburg formation/Lenoir Limestone/Little Oak Limestone. It is sometimes divided into the Blockhouse Shale and the Tellico Formation
Fossils: graptolites.
Perhaps as much as 7600 meters of Upper Pennsylvanian sandstone and shale found in Arkansas and Oklahoma as well as possibly Texas, Missouri, Kansas, Colorado, and Nebraska. The Atoka overlies the Bloyd Formation and is overlain by the Hartshorne Sandstone. It includes the following formations: Barnett Hill, Blackjack School Sandstone, Coody Sandstone, Dirty Creek Sandstone, Georges Fork Sandstone, Greenland Sandstone Member, Pope Chapel Sandstone Member, Trace Creek Shale Member,and Webber Falls Sandstone.
Fossils: ichnofossils, poorly preserved plants, a few invertebrate molds in conglomerate beds.
Nine meters of Middle Ordovician Limestone and Dolomite found in Missouri and Illinois. It overlies the Abernathy Formation/Tonti Sandstone and is overlain by the Boles Formation. It is a member of the Joachim Dolomite.
Fossils: None?
Exposures of mostly unfossiliferous Middle to Upper Ordovician black shales,sandstones and brown shales found in New York on both sides of the Hudson River from Kingston to Saratoga. Strictly speaking, it is not a formation but rather a melange of large blocks of countryside stacked up on the margin of the Paleozoic continent of Laurentia when the Iapetus Sea closed in the late Ordovician. Unlike a normal formation, there are no overlying and underlying strata. There are two facies -- a black shale facies termed the Normanskill Shale and a shale and sandstone facies called the Austin Glen Formation. Two fossiliferous subunits are recognized -- Mount Merino Chert and Snake Hill shale.
Fossils: Rarely, A few shelly fossils in turbide beds
11 to 17 meters of cherty Middle Devonian Limestone unit within the Onondaga Limestone found in East Central New York near the Herkimer-Otsego County line. It underlies the Springfield Center Limestone
Fossils: Brachiopods,others(?)
| 305m | Devonian,Lower | limestone | IL,IN,KY | Bailey/Grassy Knob | Clear Creek | equivalents | fossils:maarine invertebrates | GEOLEX link | NO cgkn link | New Harmony |
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Up to 11 meters of fossiliferous Lower Permian limestones and shale found in Oklahoma, Kansas and Nebraska. There are one or two limestone beds depending on the region. The beds are variously designated as the Bader Limestone,Hooser Shale,Eiss Limestone,Middleburg Limestone. It overlies the Stearns Shale and is overlain by the Easly Creek Shale. It is a member of the Council Grove Group/Oscar Group.
Fossils: abundant gastropods (and others?) in the limestones and shales
As much as 90 meters of Upper Silurian/Lower Devonian limestones,shales, and chert found in Illinois, Indiana, Missouri, and Kentucky. It overlies the Bainbridge limestone and underlies the Clear Creek limestone/Grassy Knob Chert. It is a member of the Bainbridge Group
Fossils: Fairly abundant? marine invertebrates
Middle and Upper Silurian found in Missouri,Illinois,Indiana. Overlies the Girardeau Limestone and is overlain by the Bailey Limestone. It includes the Seventy Six Shale,St Clair Limestone, and Mocassin Springs. It is laterally equivalent to the Clifton Limestone
Fossils: Marine invertebrates-corals,etc
A dubious name for roughly 10 meters of fossiliferous Upper Ordovician Shale and limestone found in Kentucky Southwest of Cincinnati. It overlies the Rowland Formation and is overlain by the Saluda Dolomite. It is considered to be the middle member of the Drakes Formation. It is roughly equivalent to the Liberty Formation further to the East and to the Lower Whitewater Formation in SouthWest Ohio and adjacent Indiana..
Fossils: Brachiopods,corals,cephalopods,bryozoa
A Lower Silurian marine dolomitic sandstone with minor shale interbeds. It is a western facies of the Devils Hole Sandstone of the Medina Group. It is found in Western New York(?) and adjacent Ontario It overlies the Power Glen Shale and is overlain by the Grimsby Sandstone
Fossils: Unknown. At least one starfish reported?
Up to 450 meters of Upper Mississippian limestone with minor sandstone found in Alabama, Mississippi, Georgia, Kentucky, and Tennessee. It overlies the Hartselle Formation and is overlain by the Pennington Formation. Laterally equivalent to the Parkwood Formation
Fossils: Abundant crinoid fragments and bryozoa
Up to 30 meters of Lower Permian limestone and chert found in Oklahoma(ne),Kansas(e),and Nebraska(se) It is sometimes subdivided in to a lower Florence Limestone, intermediate Oketo Shale and an upper Fort Riley Limestone It overlies the Matfield Shale and is overlain by the Holmesville Shale
Fossils: Marine invertebrates in the ahales -- brachiopods, crinoids, echinoids
160 meters of Silurian dolomites found in Ohio and adjacent Michigan. It overlies the Salina Group and is overlain by the Sylvania Sandstone of the Detroit River Group It includes the Tymochtee shales and limestones,Greenfield dolomite,Put-in-Bay dolomites,and Raisin River dolomite
Fossils: Unknown.
Up to 20 meters of massive Mississippian Sandstone found in Missouri, Oklahoma and Arkansas. Overlies the Fayetteville Shale/Moorefield Shale/Boone Limestone/Ruddell Formation/Hindsville Formation/Keokuk Limestone. Is overlain by Archimedes Limestone/Marshall Shale. It is equivalent to the Wyman Sandstone
Fossils: brachiopods,gastropods,bivalves,cephalopods
40 meters of heterogeneous Upper Mississippian sediments -- limestone, chert, and shale found in Eastern Kansas and Oklahoma. The Baxter Creek is a member of the Boone Formation. It overlies the Short Creek Oolite and is overlain by the Mocassin Bend Formation.
Fossils: Fossils: crinoids, bryozoans, brachiopods, sponge spicules, corals, mollusks, blastoids, fish remains, trilobites
100 meters and up of red Middle Ordovician sandstones found in Virginia, West Virginia, Tennessee, and Georgia. It overlies the Sevier Shale/Ottosee Shale and underlies the Chattanooga black shale/Clinch Sandstone.
Fossils: Mostly unfossiliferous, but some beds contain Ordovician marine invertebrates.
10 meters of Middle Pennsylvanian coal found in Virginia(sw). It occurs about 1.3 meters above the top of the Chicken Ridge Sandstone of the Kanawha Formation.
Up to 8 meters of Lower Permian shale bracketed by two fossiliferous marine limestones found in Oklahoma, Kansas(e). and Nebraska(se). It is subdivided into the Cottonwood Limestone, Florena Shale, and Morrill Limestone Members It overlies the Eskridge Shaleand is overlain by the Stearns Shale. It is a member of the Council Grove Group.
Fossils: Marine invertebrates in the shale
Up to 12 meters of massive, oolitic, siliceous, ferruginous Upper Mississippian limestone found in Kentucky and Indiana. It overlies Mooretown sandstone/Bethel Formation and is overlain by the Sample sandstone/Reelsville Formation/Mansfield Formation. It is assigned variously to the West Baden Group/Renault Formation/Ridenhower Formation
Fossils: Marine invertebrates - best in upper part of formation. Blastoids, brachiopods, crinoid columnals.
A Middle Silurian marine shale with limestone interbeds found in Western New York above the Furnaceville Hematite bed. It is the Western equivalent of the Wallington Limestone further East. It is part of the Clinton Group/Reynales Formation and is overlain by the Sodus Shale].
Fossils: The limestones are reported to contain fossils -- bivalves?
20 meters of Middle Pennsylvanian sandstone or conglomerate found in Virginia and West Virginia. It overlies the Dismal Formation and is overlain by the Dotson Formation. It is a member of the Kanawha Formation
Fossils: None? Possibly some fossil plants?
Roughly 125 meters of Lower Ordovician dolomites,limestones and sandstones presumably equivalent to the Ogdensburg formation/Beekmantown Group exposed in Southwestern Quebec and adjacent Ontario. It overlies the Theresa formation and is overlain by the Huntingdon Formation-- which may be treated as a member of the Beauharnois.
Fossils: TBPL
A minor Pennsylvanian coal seam found in McCreary County Kentucky in the Lee Formation below the Rockdale Conglomerate.
Fossils: Plants?
Up to 20 meters of fossiliferous Lower Devonian Limestones of the Helderberg Group that overlie the New Scotland and Kalkberg formations and are overlain by Devonian Oriskany Sandstones.
Fossils: Abundant, diverse Lower Devonian marine fossils
15 to 35 meters of fossiliferous Uppermost Devonian gray shale found from Kentucky to Pennsylvannia and SouthEast to Virginia. It overlies Upper Devonian black shales such as the Ohio shale or their equivalents and is overlain by the Berea Sandstone. It is considered to be part of the Chattanooga Group in the Southern Appalachians.
Fossils: ammonites, conodonts
20 meters of sometimes fossiliferous Middle Devonian limestone and shale found in the Northernmost part of Michigan's Lower Peninsula. It overlies the Gravel Point Formation and is overlain by the Antrim Shale. The Beebe School Formation is a member of the Traverse Group
Fossils: Abundant marine invertebrates in some limestone beds.
Up to ten meters of fossiliferous Upper Mississippian limestone found in Illinois, Indiana, Kentucky, and Missouri. It overlies the Elwren sandstone and is overlain by the Cypress Sandstone/Big Clifty Formation/Fraileys Shale/Mansfield Formation
Fossils: abundant crinoid fragments and brachiopods, corals, mollusks
2 meters of fossiliferous gray, crinoidal Middle Devonian limestone found in Indiana(SE) and adjacent Kentucky. It overlies the Silver Creek Limestone/Louisville Limestone and is overlain by the New Albany Shale. It is considered to be a member of the North Vernon Limestone/Sellersburg Limestone.
Fossils: brachiopods, corals, pelecypods, bryozoans, and crinoids.
The term Beekmantown is widely used in the NorthEastern US and in Canada for many hundreds of meters of sometimes sandy, Lower Ordovician dolomites and limestones spanning the interval between Cambrian formations and Middle Ordovician limestones. Fossils are sometimes found -- especially in the limestone layers. The Beekmantown includes all but the lowest beds (Division A) of the early geologist's Calceriferous.
Fossils: TBPL
An Upper Devonian marine black shale formation found near the base of the West Falls Group of South Central New York where it may be treated either as an independant formation of as a member of the Rhinestreet Black Shale. It overlies the uppermost Millport Black Shale and is overlain by the Meads Creek Black Shale of the Rhinestreet Shale Formation
Fossils: Possibly in sandstone layers within the shale. Fossils other than very occasional fish are rare in the shales of New York Devonian black shales.
80 meters of Lower Pennsylvanian sandstone/conglomerate found in Kentucky, Tennessee, and Virginia. It overlies the Hensley Formation and is overlain by the Hance Formation It is a member of the Lee Formation/Breathitt Formation
Fossils: Plants-Sigillaria
A Lower Ordovician marble composed of interbedded dolomite and limestone found in West Central Vermont. It is laterally equivalent to the Bridport Dolomite further West. It overlies the Burchards Formation/Weybridge Limestone. It is assigned by various authors to the Chipman Formation and the Providence Island Formation
Fossils: sparse due to alteration of the rock
| 34m | Devonian,Middle | shale,limestone | MI(ce) | [Rogers City #RogersCity ] | Rockport Quarry Limestone | fossils:marine invertebrates | GEOLEX link | NO cgkn link | Traverse |
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About 6 meters of fossiliferous Upper Ordovician marine Limestone found in Southwest Ohio and adjacent Indiana and Kentucky. It overlies the Fairmont Formation/Miamitown Shale/Kope Formation and is overlain by the Corryville Formation. It is a member of the McMillan Formation/Grant Lake. It is laterally equivalent to the Fairview Formation/Dillsboro and is a part of the Cincinnati Group.
Fossils: very abundant Bryozoa, Brachiopods
Roughly 110 meters of fossiliferous coarse grained Black River age Middle Ordovician limestone found in Tennessee, Virginia, and West Virginia. It overlies the Peery Foration and is overlain by the Gratton Limestone.
Fossils: TBPL
Up to 9 meters of Lower Permian calcaerous shale or limestone found in Kansas and Nebraska(c). It overlies the Glenrock Limestone and is overlain by the Howe Limestone. It is a member of the Red Eagle Limestone/Elmdale Shale of the Council Grove Group
Fossils: abundant brachiopods, some echinoderms, algae
Middle Ordovician limestone found in Kentucky where it is the uppermost member of the Lexington Limestone. It overlies the Jessamine Limestone It is overlain by the Cynthiana Formation
Fossils: Probably present and reasonably abundant?
Up to 50 meters of shaly Middle Ordovician Limestone found in Tennessee, Kentucky, and Virginia. It overlays the Woodway Limestone and is overlain by the Hardy Creek Limestone. It is a member of the Chickamauga Group and in laterally equivalent to the section from the Dot Formation to the Reedsville Shale.
Fossils: Marine invertebrates locally abundant in the lower part of the formation.
As much as 100 meters, but usually much less, of fossiliferous Uppermost Devonian sandstone found from Kentucky to Pennsylvannia and SouthEast to Virginia. It overlies the Bedford Shale and is overlain by Mississippian beds. It is considered to be part of the Chattanooga Group in the Southern Appalachians.
Fossils: ammonites, conodonts
90 meters of non-calcerous Middle Devonian gray-black shale found in the Lower Marcellus Shale interval in the Northern Catskill region of East Central New York. It overlies the Onondaga Limestone and is overlain by the Otsego Sandstone member of the Marcellus Shale.
Fossils: some beds have marine invertebrates
Upper Silurian dolomites found in Northern New York and adjacent Ontario in the Ontario Plain. It is a member of the Salina Group. It overlies the Camillus formation mixed sediments and is overlain by the Cobleskill Limestone formation. Noted for its Eurypterid fossils
Fossils: TBPL
Up to 30 meters of Upper Mississippian sandstone found in Illinois,Indiana,Missouri,and Kentucky. The name is also used by some authors for similar beds in Mississippi and Alabama. It overlies the St Genevieve Limestone/Renault Formation/Paoli Limestone and is overlain by the Ridenhower Shale/Gasper Limestone/Paint Creek Formation/Beaver Bend Limestone.
Fossils: poorly preserved brachiopods,bryozoa and plant stems.
45 meters of Lower and Middle Pennsylvanian shale and silstone found in Kentucky, Tennessee, in Virginia and West Virginia. It overlies the Manchester Coal/Corbin Sandstone/Lee Formation/Grundy Formation and is overlain by various coal beds. It is variously assigned to the Breathitt Formation,Slatestone Formation,Wise Formation,Kanawha Formation, and Pikeville Formation
Fossils: A few marine invertebrates
Up to 150 meters of coarsely crystalline Upper Cambrian dolomite found in Alabama where it overlies the Ketona Dolomite and is overlain by the Copper Ridge Dolomite.
Fossils: None
An obsolete term for Permian shales, limestones and evaporites found in Kansas and Nebraska. The Big Blue beds are included in the Neosho Shales, Chase Limestone, and Wellington Shales in modern usage.
Fossils: Marine Invertebrates probably present
A 1 meter thick Lower Pennylvanian coal bed within the Norton Sandstone It lies above the Puncheon Camp coal bed/Kennedy Coal bed and below the Lower Banner Coal
Fossils: Plants?
Up to 30 meters of laminated, phosphatic Middle Ordovician Limestone with minor shale found in North Central Tennessee. It overlies the Hermitage Formation and is overlain by/laterally equivalent to the Cannon Limestone The Bigby and Cannon are treated as a single formation by many authors. The Bigby-Cannon beds are overlain by the Catheys Limestone and are part of the Nashville Group
Fossils: abundant marine invertebrates-brachiopods, bryozoans, corals, gastropods, and stomatoporoids.
Up to 40 meters of Upper Mississippian often thick bedded sandstone found in Illinois, Indiana, Kentucky(w) and Tennessee. It overlies the Beech Creek Limestone/Girkin Formation/Elwren Sandstone and is overlain by the Indian Springs Shale/Golconda Limestone/Haney Formation/Mansfield Formation. It is laterally equivalent to the Fraileys Shale and Hartselle Formation It is variously assigned to the Stephensport Group,Fraileys Shale,Golconda Group
Fossils: A few brachiopod/bivalve casts in some beds as well as marine invertebrates in the uppermost (Indian Springs Shale) beds where they are developed)
10 meters of Lower Devonian calcaerous marine shale found in Virginia and West Virginia where it separates the upper and lower limestone members of the Keyser Limestone. The Big Mountain is laterally equivalent to the Clifton Forge Sandstone It is a member of the Keyser Limestone
Fossils: some fossils in thin limestone beds?
About 100 meters of Upper Cambrian dolomite,sandstone,shale, and limestone found in Maryland,Pennsylvannia,Virginia and West Virginia. It overlies the Elbrook Dolomite and is overlain by dolomitic members of the Conococheague Formation The Big Spring Station is the lowest member of the Conococheague Formation
Fossils: thrombolites, possibly a few body fossils
A fossiliferous Upper Ordovician shale with thin limestone units found above the Lindsay Formation of the Simcoe Group in NorthEast Ontario and adjacent Quebec. It is the equivalent of the Blue Mountain formation in Western Quebec and the Utica Shale in the US. The Billings is overlain by the Carlsbad Formation.
Fossils: TBPL
An Upper Devonian marine Conglomerate found within the Venango Formation of the Conewango Group in NorthWest Pennsylvania. It is one of a number of pebble/quartzite conglomerates thought possibly to represent river basin deposits found in the Uppermost Devonian beds of New York and Pennsylvania. It is overlain by the North Warren Shale.
Fossils: Unknown. Probably?
Upper Silurian sometimes calcerous sandstones, shales and thin bedded limestones found in East Central New York. It overlies the High Falls Shale and is overlain by the Wilbur Limestone/Rondout Formation
Fossils: Unknown.
Up to 15 meters of fossiliferous Middle Silurian limestone found in Ohio and Kentucky. It overlies the Crab Orchard Formation and is overlain by the West Union Formation/Lilley Dolomite/Ohio Shale
Fossils: Abundant marine vertebrates - brachiopods, trilobites, corals, etc
A generic name for fossiliferous Middle Ordovician Limestones found in an arc from Virginia North to Quebec then West as far as Illinois and in the Upper Peninsula of Michigan. They lie above recognizably older Middle Ordovician Limestones such as the Chazy and below the uppermost Middle Ordovician rocks typically referred to the Trenton Group. West of the Appalachian region, the term 'Black River' tends to be an age designation rather than a lithological term. The Black River consists of limestones and shales in contrast to the purer limestones of the Trenton. Formations assigned to the Black River include Chaumont (NY), Lowville (NY*,PA*,VT), Pamelia (NY*); Watertown (NY*), Gull River (PA,NY); Isle La Motte (NY,VT), Amsterdam (NY*,VT*); Bony Falls (MI,NY); Lincolnshire (VA*), Peery (VA*); Ward Cove (VA*); Benbolt (VA*); Witten (VA*); Wardell (VA*);
Fossils: Some beds contain abundant, diverse marine fossils
| Middle Ordovician Trenton Group | |||
| MIDDLE ORDOVICIAN BLACK RIVER GROUP | |||
| SOUTHERN ONTARIO | NORTHWEST NEW YORK | CHAMPLAIN VALLEY | WESTERN QUEBEC |
| Gull River | Watertown Limestone | Amsterdam Limestone | Gull River |
| Shadow Lake | Lowville Limestone | ||
| Shadow Lake | Pamelia Limestone | Pamelia Limestone | |
| Lower Ordovician Chazy Group Limestones | |||
Up to 35 meters of Middle Ordovician Shale, Limestone and cherty Dolomite found in Georgia, Tennessee, Virginia and West Virginia. The Blackford overlies Beekmantown age beds/Mascot Dolomite/Knox group and is overlain by the Elway Limestone/Five Oaks Limestone. Depending on location it is a member of the Lurich Formation/Chickamauga Group/Cliffield Group/Formation/Five Oaks Formation/Murfreesboro Formation/Peery Limestone
Fossils: Present?
A Lower Ordovician sandy dolomitic limestone found in Arkansas,Missouri,and Illinois. It has some complex interrelationship with the similar Smithville Dolomite and Powell Limestone/Dolomite.
Fossils: Unknown. None?
Fossiliferous Upper Ordovician shale, clay and limestone found in Southwest Ohio. The Blanchester beds overlie the Clarksville beds of the Waynesville Formation. They are overlain by the Liberty Formation. They are part of the Richmond Group.
Fossils: Marine invertebrates are common, well preserved, and abundant.
Up to 180 meters of Upper Devonian sandstone, siltstone, and shale found in Virginia, West Virginia, Maryland and Pennsylvania. It overlies the Briery Gap Sandstone and is overlain by the Pound Sandstone. It is a member of the Foreknobs/Greenland Gap Formation/Group.
Fossils: Brachiopods - Spinatrypa, Pseudatrypa, Cypricardella, Prodoctella, Cyrtospirifer
Up to 300 meters of grey, calcaerous Middle Ordovician shale with minor limestone found in Tennessee and Georgia. It overlies the Lenoir Limestone and underlies the Tellico Formation. It includes the Toqua Sandstone and Whitesburg Limestone.
Fossils: Marine invertebrates in the limestones?
Up to 600 meters of red Upper Silurian shales occupying the lower Lockport and lower Salina Group interval between the Clinton Group and Upper Salina Group in the northern part of the Applachians -- New Jersey, South Central New York, Pennsylvania, Maryland, West Virginia, Virginia. Many beds are marine, others are brackish water and others non-marine.
Fossils: Ichnofossils, ostracods, roots
A somewhat hazily defined Group of Middle Ordovician limestones and shales found in Tennessee in the interval between Chazy age and Black River age Modern usage is to assign the "Blount" beds to the Chickamauga Group
Fossils: Marine invertebrates in some beds
About 60 meters of Lower Pennsylvanian shale with minor limestone and calcaerous sandstone and found in Arkansas and Oklahoma. It overlies the Hale Sandstone It is sometimes divided into Brentwood Limestone, Dye Shale, Kessler Limestone, Trace Creek Member, and Woolsey Member. Some workers consider the Bloyd to be part of the Atoka Formation
Fossils: marine invertebrates
400 meters of progressively less calcaerous Upper Mississippian shale found in Kentucky, Virginia, and West Virginia. It overlies the Greenbrier Limestone/Slade Formation and is overlain by the Hinton Sandstone. It is laterally equivalent to the Paragon Formation/Glen Dean Formation/Newman Limestone. It is considered to be a member of the Mauch Chunck Group in the East and the Pennington Group further West
Fossils: abundant marine invertebrates in some beds.
Up to 75 meters of sparsely fossiliferous Upper Ordovician shale with thin limestone units found above the Lindsay Formation of the Simcoe Group in SouthEast Ontario. It is the equivalent of the Cobourg Formation,the Billings formation in Western Quebec and the Utica Shale in the US. The Blue Mountain is overlain by the Georgian Bay Formation.
Fossils: TBPL
About 10 meters of Lower Permian shale with a thin limestones found in Oklahoma, Kansas(e), and Nebraska(se). It overlies the Kinney Limestone and underlies the Florence Limestone. The age is Early Permian (Wolfcamp). The Blue Springs is a member of the Matfield Shale/Chase Group/Oscar Group
Fossils: Marine Invertebrates present in the limestones and in some shale beds
Roughly 7 meters of fossiliferous Permian shale with thin limestones and a thin coal bed in some places. It is found in Oklahoma, Kansas(e), and Nebraska(se). It overlies the Crouse Limestone and is overlain by the Funston Limestone. It is a member of the Council Grove/Oscar Groups and was at one time included in a Bigelow Formation.
Fossils: gastropods, brachiopods, bryozoa
About 100 meters of Lower Ordovician thin bedded limestone, shale, and dolomite found in the Southwest Arm area of Newfoundland. It overlies the Watts Bight Limestone and is overlain by the Catoche Formation. It is a member of the St George Group
Fossils: conodonts. other marine invertebrates
Abundantly fossiliferous Middle Ordovician Black River and Trenton age limestones found in Ontario, and Westernmost Quebec. It overlies the Gull River formation and is overlain by the Verulam formation. The terminology has also been applied to rocks exposed along Lake Erie in Pennsylvania.
Fossils: Abundant, diverse marine fossils in the upper beds
Middle Devonian cherty marine limestones and dolomites found in Michigan, Ohio, New York, Ontario, and Pennsylvania. It corresponds to the Lower part of the Columbus Limestone in Ohio. It unconformally overlies Lower Devonian beds and is overlain by Onondaga/Dundee/Detroit River Limestones
Fossils: Present. No details
About 9 meters of thin layers of silty and vuggy Middle Ordovician dolomite with silt, chert and limestone found in Missouri and Illinois. It overlies the Augusta Dolomite and is overlain by the Defiance Dolomite. It is a member of the Joachim Formation.
Fossils: None?
As much as 150 meters of Upper Cambrian dolomite with minor limestone found in Arkansas, Missouri, Illinous, Colorado, Nebraska, Oklahoma, and Minnesota. It overlies the Lamotte Sandstone and is overlain by the Elvins Group - Davis Shale or Potosi Dolomite. It is also known as the St Joseph Limestone. It is laterally equivalent to the Eau Claire and Arbuckle formations
Fossils: Present. Diverse faunas in basal beds in some areas
Fossiliferous Middle Ordovician Black River age marine limestones found in the Eastern part of Michigan's Upper Peninsula. The Bony Falls formation is overlain by the Trenton age Chandler Falls Chandler Falls formation. Overlies Cambrian sandstones(?). http://weblex.nrcan.gc.ca/html/001000/GSCC00053001579.html]
Fossils: TBPL
Up to 125 meters of Mississippian limestone and chert found in Arkansas,Kansas,Oklahoma and Missouri. Overlies the Chattanooga Shale and is overlain by the Batesville Sandstone. Has been divided into the Walls Ferry Formation,St Joe Limestone, Reeds Spring Formation, Grand Falls Chert, Joplin Formation, Short Creek Oolite, Baxter Springs Formation, and Moccasin Bend Formation.
fossils: crinoid stems, marine invertebrates
25 to 33 meters of dark, unfossiliferous Upper Silurian limestone found near the junction of New York, New Jersey, and Pennsylvania. The Bossardville Ferry overlies the Poxono Island shale and is overlain by the Decker Formation
Fossils: Essentially none
Roughly 20 meters of brown granular Middle Ordovician Limestone found in Tennesee and Virginia. It overlies the Linconshire Formation/Lenoir Limestone and is overlain by the Liberty Hall Formation/Whitesburg Formation It is a member of the Edinburg Formation
Fossils: diverse trilobites, Others?
Up to 50 meters of Middle Ordovician sandstone and mudstone found in Virginia and Tennessee. It overlies the Wardell Formation and is overlain by the Witten Limestone. It is a member of the Chickamauga Group.
Fossils: ichnofossils, bryozoan reefs(?), probably others
300 meters of Lower Pennsylvanian sandstone, siltstone, shale, and coal found in Kentucky, Virginia and West Virginia. It overlies the Warren Point Sandstone/Pocahontas No. 8 coal. and underlies Sewanee Sandstone. It is an informal member of the Breathitt Formation Not to be confused with the pre-Cambrian Bottom Creek complex also found in Virginia
Fossils: plants? marine fossils in uppermost beds?
50 meters of variable lithology Upper Cambrian limestone found in Tennesee and Virginia. It overlies and is overlain by unnamed shales except in areas where it overlies the Maryville formation. It is generally the middle limestone member of the Nolichucky Shale. and is laterally equivalent to the Elbrook Dolomite #Elbrook and [Maynardville Limestone.
Fossils: Algal masses, brachiopods, trilobites
About 600 meters of marine Upper Devonian shales and sandstones found in Pennsylvania, Maryland, Virginia West Virginia and Tennessee. The Brallier overlies Middle Devonian Hamilton beds and is overlain by the [Greenland Gap/Chemung Group and is assigned to the Susquehanna Group,Chattanooga Group,etc
Fossils: Marine invertebrates. (Common?)
about 5 meters of pure Middle Ordovician limestone weathering to chert and calcaeurous shale found in Kentucky. It overlies the Perryville Limestone/Grier Limestone and is overlain by the Sulphur Well member/Tanglewood Limestone. The Brannon is laterally equivalent in part to the Tanglewood Limestone. The Brannon is a member of the Lexington Limestone/Cynthiana Limestone
Fossils: Sparse - A few brachiopods
up to 20 meters of basal Silurian limestone or dolomite found in Alabama, Indiana,Arkansas,Kentucky,Mississippi,Ohio, and Tennessee. In all areas the lower beds are thicker and more massive whereas the upper beds may become thin with shale interbeds.
Fossils: Marine invertebrates - more common in upper beds. Abundant in some places. It overlies the Saluda Limestone/Juniata Formation and is overlain by the Osgood Formation/Chattanooga Shale/Dayton Limestone. In Kentucky, it is considered to be a member of the Drowning Creek Formation.
A sparsely fossiliferous upper Silurian Shale occupying the stratiagraphic position above Ordovician shales and sandstones and below younger Silurian formations in Eastern New York. Further west it overlies Middle Silurian Clinton Group beds.
Fossils: TBPL
270 to 450 meters of Earliest Ordovician limestones and dolomites found in the Southern Arm area of SouthWest Newfoundland. It overlies the Petit Jardin Formation and is overlain by the Southern Arm Formation. It is a member of the St George Group
Fossils: Fossils are present.
Up to 950 meters of Lower and Middle Pennsylvanian shale, sandstone and coal found in Kentucky, Ohio, Tennessee, Virginia and West Virginia. It may be treated as a formation with Betsie Shale,Crummies,Frozen Sandstone,Jesse Sandstone,Kendrick Shale,Magoffin,Reynolds Sandstone,Stoney Fork members. It is also treated as a group including the Warren Point Sandstone,Pocahontas Formation,Bottom Creek formation,Sewanee Sandstone,Alvy Creek formation,Bee Rock Sandstone,Grundy Formation,Corbin Sandstone,Pikeville Formation,Hyden Formation, Four Corners Formation, and Princess Formation. or, alternatively, the Hance, Mingo, Catron, Hignite, and Bryson Formations
It overlies the Corbin conglomerate/Lee formation, and may be overlain by the Conemaugh and Monongahela Formations
Fossils: Marine invertebrates in some beds, plants?
A shale bed within the Middle Devonian Marcellus black shale found in North Central New York.
Fossils: Unknown
A Lower Ordovician dolomite with a few thin fossiliferous limestones found at the top of the Beekmantown Group in the Champlain Valley of Vermont and New York. It is laterally equivalent to the Chipman Formation/Beldens Limestone/Weybridge Limestone/Burchards Limestone and is overlain by various Middle Ordovician Limestones.
Fossils: invertebrate fragments in limestone beds
400 meters of thick bedded silaceous Upper Cambrian dolomite found in Alabama. It overlies Cambrian limestones and the Conasauga Shale. It is overlain by the Ketona Dolomite It is a member of the Conasauga Formation
Fossils: Crytozoon masses
Up to 37 meters of Upper Devonian sandstone with very minor shale and siltstone found in Virginia, West Virginia, Maryland and Pennsylvania. It overlies the Mallow Formation and is overlain by the Blizzard Formation. It is a member of the Foreknobs/Greenland Gap Formation/Group.
Fossils: Brachiopods - Camarotoechia, Cyrtospirifer
About 10 meters of dark blue Middle Ordovician shales found in Kenucky and Ohio. It underlies the Point Pleasant Formation. Part of Point Pleasant Formation/Clays Ferry Formation
Fossils: fairly abundant trilobites and brachiopods
40 meters of Upper Silurian white, fossiliferous limestones and calcaerous clays found in Tennessee and Mississippi. It overlies the Dixon Formation/Wayne Group and is overlain by the Hardin Formation/Linden Formation/Chattanooga Shale. Some authors subdivide the Brownsport into Beech River, Bob Limestone, and Lobelville Members.
Fossils: abundant marine invertebrates
2 meters of Upper Pennsylvanian crinoidal limestone with shale partings found in Oklahoma, Kansas(e), Nebraska(se) and Iowa. It overlies the Pony Creek Shale, and underlies the Aspinwall Shale. It is a member of the Wabaunsee Group/Vanoss Group/Admire Group/[Wood Siding Formation #WoodSiding"
Fossils: crinoid columnals, brachiopods, bryozoa, bivalves, fusulinids.
An obsolete term for up to 65 meters of Middle Pennsylvanian shale,sandstone and coal found in Kentucky, Virginia and Tennessee. It overlies the Red Spring Coal/Hignite Formation. The Bryson beds are now included in the Breathitt Formation
Fossils: Unknown. plants?
Up to 200 meters of Middle and Upper Cambrian gray to pink sandy crystalline limestone found in SouthEastern Pennsylvania where it underlies the Snitz Creek Formation. It is a member of the Conococheague Group
Fossils: stromatolites
A Lower Middle Ordovician limestone with dolomitic mottles and marble found in West Central Vermont. It is laterally equivalent to the Crown Point Formation further West and parts of the Bridport Dolomite. It underlies the Beldens Formation/Weybridge Limestone. It is assigned by various authors to the Chipman Formation and the Providence Island Formation
Fossils: Chazy age fossils in some beds
The Upppermost of the Middle Silurian Rochester Shale between Hamilton, Ontario and Brockport, New York. 8 meters or so of shale, and thin limestones. It overlies the Lewiston member of the Rochester Shaleand is overlain by the Decew Formation.
Fossils: sparse. Conodonts
1300m of Middle to Upper Ordovician marine Martinsburg Shale found in Northeastern Pennsylvania and adjacent New Jersey. It overlies the Jacksonburg Limestone and is overlain by the Ramseyburg Formation.
Fossils: Sparse. Graptolites and a few shelly fossils have been recovered at scattered localities. Small Graptolite fragments have been reported from other outcrops.
An Upper Cambrian-Lower Ordovician pink-gray carbonate rock found in Oklahoma and Missouri. It apparently overlies the Sylvian Shale and is overlain by the Signal Mountain Limestone/Chapman Ranch Formation It is the basal member of the Arbuckle Group.
Fossils: silicified brachiopods in lower parts
Up to 65 meters of interbedded shale and fossiliferous Upper Ordovician limestone found in Kentucky, Southwest Ohio and adjacent Indiana. It overlies the Bellevue Limestone/Grant Lake Limestone. It is overlain by the Preachersville Formation/Brassfield Limestone.
Fossils: Abundant, diverse fossils in the limestone beds - brachiopods, bryozoans, solitary and colonial corals, gastropods, cephalopods, pelecypods, crinoids, trilobites, and ostracodes
A regional name for the Middle Devonian Onondaga Limestone Group in the Monroe County area NorthEast Pennsylvania and possibly in adjacent New Jersey and New York. 65 or more meters of fossiliferous (?) Middle Devonian Limestone overlying the Esopus Grit and overlain by the Marcellus Black Shale].
Fossils: Probably
About 40 meters of Medina age Lower Silurian shales and some thin limestones exposed in Western New York and West across Ontario to the Upper Peninsula of Michigan. It overlies the Manitoulin Dolomite.
Fossils: Probably
About 100 meters of flaggy, red Middle Silurian sandstone found in Virginia and West Virginia. It overlies the Tuscarora Formation and is overlain by the Rockwood Formation. It is considered to be a member of the Rose Hill/Clinton Group.
Fossils: Ichnofossils?
Two layers of Upper Cambrian sandstones found in Southwest Quebec where it overlies the Covey Hill Formation and is overlain by the Theresa Formation. It is regarded as an equivalent to the Potsdam Formation in Northern New York, the Nepean formation in Ontario equivalent and the the Strites Pond Formation to its East. Fossils in Cairnside Formation are limited to ichnofossils.
Fossils: TBPL
A nineteenth Century term for dolostones,sandstones, and limestones found above the Potsdam sandstones and below Middle Ordovician limestones. It was divided into a lower (Cambrian and Lowest Ordovician) sandy Division A (The modern Theresa Formation and its numerous equivalents) and a more Calcearous Lower Ordovician Division B-E the modern Beekmantown Formation.
Fossils: TBPL
About 40 meters of fossiliferous Upper Ordovician limestone with shale and siltstone found in north central Kentucky It overlies the Garrard Formation and is overlain by the Ashlock Formation. It is laterally equivalent to the Fairview Formation and Leipers Limestone.
Fossils: abundant brachiopods and bryozoa
Up to 6 meters of sparsely fossiliferous Lower Silurian shale, siltstone, sandstone lying between the Early Silurian Medina Group and the overlying Clinton Group in the Niagara region of New York and Ontario.
Fossils: ostracods. others?
Interbedded Upper Silurian shales,dolomites,and gypsum-found in Northern New York in the Ontario Plain. It is a member of the Salina Group. It overlies the Syracuse formation evaporites and is overlain by the Bertie Limestone formation. Fossils are reported -- arthropods and brachiopods.
Fossils: TBPL
Up to 100 meters of thick bedded Middle Ordovician limestone and sometimes dolomite found in Kentucky(nc). It is the oldest formation exposed in Kentucky. It is overlain by the Oregon Formation It is a member of the High Bridge Group
Fossils: Not abundant - ostracodes, trilobites, brachiopods, corals, bryozoans, pelecypods, and nautiloids
A Lower Pennsylvanian Coal Seam associated with the Campbell Creek Limestone found in West Virginia
Fossils: Unknown. Plants?
A thin (30cm), discontinuous, layer of Lower Pennsylvanian marine limestone and calcaerous shale found in West Virginia. It lies above the Campbell Creek Coal and below the Williamson Coal It is a member of the Kanawha Formation
Fossils: Occasional marine and brackish water invertebrates
Fossiliferous marine Upper Devonian shales and sandstones found in Western New York where they overlie the West Falls Group/Chemung Formation and underlie the Conneaut Group/Portage Group. As one moves inland from Lake Erie, the Conneaut Group replaces the Canadaway until eventually, the Conneaut Beds lie unconformally on rocks of the Sonyea Group. Formations assigned to the Canadaway include the Dunkirk Shale-Canaseraga,Gowanda=Chemung=Caneadea,Laona Sandstone,Westfield Shale-Rushford,Shumla Sandstone,Northeast Shale-Machias,Cuba Sandstone
Fossils: TBPL
Almost 100 meters(?) of fossiliferous grey marine shale and siltstone Upper Devonian Sandstone found in New York. It is a member of the Canadaway Group and is the Easterly equivalent of the upper Dunkirk Shale. In New York, it overlies, the Canaseraga Sand and is overlain by the Gowanda Formation.
Fossils: A few ichnofossils?
The Canajoharie consists of often fossiliferous black Middle Ordovician shales found in the lower (Eastern) Mohawk River Valley of New York where it is differentiated from the overlying Utica shales by faunal differences. Modern authors will probably tend to include the Canajoharie in the Flat Creek member of the Utica formation.
Fossils: TBPL
As much as 50 meters(?) of fossiliferous black marine Upper Devonian Sandstone found in New York. It is a member of the Canadaway Group and is the Easterly equivalent of the Dunkirk Shale. In New York, it overlies, the West Falls Group and is overlain by the Gowanda Formation.
Fossils: Upper Devonian (Chemung) faunas in black sandstone
About 40 meters of Middle Ordovician dark gray limestone found in Alabama, Georgia,Tennessee and Virginia. It overlies the Hermitage Formation and is overlain by the Eden Group/Catheys Formation. It is laterally equivalent to the Bigby Limestone, Flanagan Limestone, and Perryville Limestone, and the Catheys formation. It is a member of the Nashville Group.
Fossils: brachiopods, bryozoans, and gastropods
18 to 30 meters of Middle Devonian clacerous black Shale and fossiliferous limestone found in Central New York where it overlies the Stafford Limestone and is overlain by the Skaneateles Shale.
Fossils: Middle Devonian (Hamilton) faunas
A term for (some?) Chazy limestone beds in Quebec (and Ontario).
Fossils: TBPL
Up to 15 meters of uppermost Lower Devonian glauconitic shale and siltstone found in Eastern New York. It is a member of the Tristates Group. It overlies the Esopus formation and underlies the Middle Devonian Onondaga formation.
Fossils: Fossils: Abundant Zoophycus. Other fossils are diverse, but not terribly common
An Upper Ordovician shale and calcerous shale formation found above the Billings Formation in NorthEast Ontario and adjacent Quebec. It is the equivalent of the Georgian Bay formation in SouthWest Ontario and the Lorraine Shale in the US. The Carlsbad is overlain by the Queenston Shale.
Fossils: TBPL
Same as Carters Creek Limestone. Up to 30 meters of Trenton age Middle Ordovician limestone found in Tennessee.
Fossils: Marine invertebrates
15 to 30 meters of fossiliferous Black River age Middle Ordovician limestone found in Tennesee, Alabama and Georgia. It overlies the Lebanon Limestone and is overlain by the Hermitage Formation Some authors identify it as the Lowville Limestone
Fossils: abundant Black River age Ordovician marine fossils. stromatoporoids,corals,algae,bryozoans,corals,gastropods,ostracodes,and brachiopods.
As much as 70 meters of Upper Devonian gray to green shale found in the Sonyea Group in Western New York and other states in the Appalachian Basin above the Middlesex Black Shale Beds. It is overlain by the Nunda Group. It is laterally equivalent to the upper Enfield Formation And Rye Point Formations ]further East.
Fossils: marine fossils-cephalopods,bivalves,gastropods. Said to be fairly abundant.
Lower Silurian Limestones and Shales corresponding to the Medina Group found in Canada from the Niagara Falls area to Manitoulin Island in Lake Huron. Modern practice is to use Medina Group terminology for these beds.
Fossils: probably
Up to 80 meters of fossiliferous Middle to Upper Ordovician limestones and shales found in Alabama, Georgia, Kentucky, Tennessee, And Virginia. It overlies the Bigby Formation/Cannon Limestone and is overlain by the Leipers Limestone. The Catheys lithology is similar to the Leipers Limestone but the two are separated by an unconformity. The Catheys is a member of the Nashville Group and is laterally equivalent to the Clays Ferry Formation and Kope Formation
Fossils: brachiopods, bryozoans, corals, gastropods, and stomatoporoids
Up to 160 meters of grey fossiliferous Lower Ordovician limestones with minor dolomites found in SouthWestern Newfoundland. It overlies the Boat Harbour Formation/Isthmus Bay Formation and is overlain by the Aguathuna Formation. It is a member of the St George Group
Fossils: trilobites,brachiopods,bryozoa,algae,gastropods,sponges,cephalopods,eocrinoids,receptaculites,ostracods
An obsolete term for about 100 meters of Middle Pennsylvanian shale, sandstone and coal found in Southeast Kentucky. The uppermost bed is sometimes broken out as the Jesse Sandstone. The beds overlie the Poplar Lick Coal/Wallins Creek Coal/Fire Clay Coal and is overlain by the Hignite Coal or equivalent beds, In modern usage, it is a member of the Breathitt Formation.
Fossils: Unknown
1000 meters or more of Upper Devonian deltaic siltstone, sandstone, conglomerate and shale found primarily in Eastern Pennsylvania, but lapping over into adjacent areas. In New York, it is present only in the SouthEast where there is a single Delaware River member recognized.
The term "Catskill" is also used as a "facies" term to identify the Eastern non-marine equivalents of shallow water formations found further West which are the Chemung Facies. Thus, in the Sonyea Group, the Catskill formation is the Walton and the Chemung Facies formation is the Triangle Formation.
Fossils: plant fragments
Fossiliferous(?), marine(?) Upper Devonian sandstones,shales, and conglomerate found in SouthWestern New York and Northwestern Pennsylvania and Ohio. It overlies similar beds without conglomerate of the Conneaut Group and underlies the Oswayo Formation. It is the lower formation in the Conewango Group. It has also been referred to as the Venango Formation. It includes the Panama Conglomerate, Pope Hollow, Salmanaca, Tunangwant, and Wolf Creek Conglomerate Members.
Fossils: TBPL
A Lower Pennsylvanian coal found in Pennsylvania and West Virginia. In some regions, it it is separated into two beds by a sandstone wedge. It lies above the Williamson Coal and below the Peerless Coal It is equivalent to the Kittanning Coal
Fossils: Unknown
A widespread unit of fossiliferous limestone that separates the Skaneateles and Ludlowville Shales of the Middle Devonian Hamilton Group in Northern New York.
Fossils: TBPL
130 meters of Middle Pennsylvanian sandstone found in West Virginia. It overlies black flints of the Kanawha Formation and is overlain be the Conemaugh Formation
Fossils: non-marine microfossils (palynomorphs)
85 meters of Lower Permian flinty limestones and shales found in Oklahoma,Kansas,and Nebraska. Includes the Barneston Limestone,Blue Springs Shale,Cresswell Limestone,Doyle Shale,Fort Riley Limestone, Grant Shale,Herington Limestone,Matfield Shale,Nolans Limestone,Odell Shale,Threemile Limestone,Winfield Limestone,Wreford Limestone. It overlies the Neosho Shales/Council Grove Group and is overlain by the Big Blue Group/Sumner Group.
Fossils: brachiopods and bivalves
A sequence of late Middle Devonian to Mississippian age black shales found from Oklahoma East to Georgia and North to Ohio and Virginia. It varies in thickness from 10 to nearly 400 meters. It corresponds roughly to the Ohio black shale which can, in turn be traced into a number of Upper Devonian black shale beds in New York. Nomenclature of members varies from place to place as do the underlying and overlying formations.
Fossils: ichnofossils, conodonts, plants, fish, brachiopods-Lingula,Bariosella
An obsolete term for the Middle Ordovician Trenton/Black River age Watertown Limestone -- a dark gray limestone found in Northern New York and adjacent Ontario on and East of Lake Ontario. It overlies the Lowville formation
Fossils: TBPL
Upper Devonian marine shales and sandstones found in Western New York and adjacent Pennsylvania. It is a member of the Conneaut Group It is considered to include the following formations-members: Unit: Dexterville, Germania, Haymaker, Welllsville and Whitesville. It overlies the Canadaway Group and is Overlain by the Conewango Group.
Fossils: brachiopods, gastropods, bivalves, crustacea, sponges, rarely fish.
Upper Devonian marine shale found in Eastern Ohio an West Virginia It occupies the interval in the Ohio Shale between the underlying Huron black shale and the overlying Cleveland black Shale. The Chagrin is laterally equivalent to the Three Lick Bed to its South but much thicker -- over 400 meters. It is laterally equivalent to the Riceville Shale.
Fossils: a few brachiopods, bivalves, cephalopods, ichnofossils.
More than 300 meters of fossiliferous Middle Ordovician (Chazy/Black River/Trenton Age) limestone found in Pennsylvania, Maryland, Virginia and West Virginia. It overlies the Athens Shale/Stones River limestones/Lenoir limestone. Some authors assign calcaerous shales at the top of the Chambersburg to the Martinsburg. The Chambersburg had been subdivided into the Shippensburg formation, Mercersburg formation, and [Greencastle formation #Greencastle]. Another subdivision is Lincolnshire limestone/Edinburg formation/Oranda formation
Fossils: The thin, dark limestone beds contain abundant fossils
About 50 meters of gray cherty Upper Cambrian dolomite found in Tennessee and Virginia. It overlies the Low Hollow Limestone and is overlain by the Copper Ridge Dolomite. It is a member of the Maynardville Limestone of the Knox Group.
Fossils: abundant stromatolites, otherwise very sparse
Middle Devonian Trenton Age limestone, shale, conglomerate, and dolomite found in the Upper Peninsula of Michigan where it overlies the Bony Falls Limestone and is overlain by the Groos Quarry Limestone
Fossils: Marine Invertebrates -- trilobites(11 taxa), gastropods, most likely others.
About 25 meters of Upper Cambrian beach sandstones and siltstones with a basal gravel conglomerate found in Michigan's Upper Peninsula. It overlies the Jacobsville Sandstone and is overlain by the Miners Castle Formation It is a member of the Munising Group
Fossils: ichnofossils
Lower Ordovician limestone found in Oklahoma. It overlies the Butterly Dolomite and is overlain by unnamed shallower water limestones also of the McKenzie Hill Formation. The Chapman Ranch is the lower member of the McKenzie Hill Formation of the Arbuckle Group
Fossils: gastropods,cephalopods
Fossiliferous shaly brown Middle Devonian limestone found in Northern Lower Michigan. It overlies the Gravel Point Formation and is overlain by the Petoskey Formation. It is a member of the Traverse Group
Fossils: trilobites, ostrocods, pelecypods, hydrozoans, bryozoans, crinoids, brachiopods, and corals
Roughly 30 meters of often fossiliferous lowest Middle Ordovician mudstone and limestones. It is often broken into three formations - Day Point, Valcour, and Crown Point. It overlies Lower Ordovician Beekmantown rocks in the Champlain Valley of New York and Vermont as well as adjacent Quebec. The Chazy is overlain by rocks of the Black River Group. It may be equivalent to the Laval formation in Quebec and the Carillon Formation in Ontario and Quebec. It lays claim to having the oldest coral reefs yet identified in its upper portion.
| Middle Ordovician Black River Limestones | ||
| MIDDLE ORDOVICIAN CHAZY GROUP | ||
| CHAMPLAIN VALLLEY | QUEBEC-ONTARIO | QUEBEC |
| Valcour limestone | Carillon | Laval |
| Crown Point Limestone | Carillon | Laval |
| Day Point Limestone | Carillon | Laval |
| Lower Ordovician Beekmantown Group | ||
Fossils: Abundant, diverse fossils in some beds -- Trilobites, Brachiopods, Corals, Bryozoa, Cephalopods, Gastropods, Crinoids, etc
A widespread unit of fossiliferous Upper Devonian marine bituminous shales with calcerous concretions and pyrite found above the Hamilton formation in Ontario,South Central New York and South to the Virginias. In New York it may also be called the Portage. In the Virginias, the Foreknobs.
The term "Chemung" is also used as a "facies" term to identify the Upper Devonian shallow water-marine equivalents of deeper water Portage facies found further West. The non-marine facies further East are the Catskill facies
Fossils: TBPL
Up to 450 meters or more of Lower Ordovician marine dolomite with soft, mealy chert. It overlies the Copper Ridge Dolomite in Georgia, Alabama, Tennessee, Kentucky and Virginia. It is overlain by the Longview Dolomite/Lambs Chapel. It is considered to be equivalent of the Gasconade Dolomite Frederick Formation and Little Falls Formation. It is a member of the Knox Group/Beekmantown Group.
Fossils: Fossils reported from upper part
Several hundred meters of Upper Devonian redbed shales the Catskill Group found in NorthEastern Pennsylvania and adjacent New York. They overlay marine beds of the Trimmers Rock Formation and are overlain by the Honesdale Sandstone or Damascus Formation.
Fossils: Fish scales and algal masses in limy conglomerates near base.
A widespread unit of sandstone and/or limestone found within the Lower Devonian Marcellus Shale of the Hamilton Group. In some areas the nomenclature identifies the lower Marcellus below the Cherry Valley as the Mount Marion formation and the upper Marcellus as the Oatka Creek Formation.
Fossils: TBPL
400 to 600 meters of Middle and Upper Ordovician Limestones found in Alabama,Georgia,Tennessee,Kentucky, and virginia. It overlies the Knox Dolomite and is overlain by the Rockwood Formation/Sevier Shale. The terminology is very confused and complex. Modern usage considers the Chickamauga to be a group composed of a number of limestone/dolomite units whose names and nature seem to differ regionally ... or worse.
Fossils:
6 meters of Middle Pennsylvanian sandstone found in Virginia. It overlies the Bearwallow Sandstoneis overlain by the Bearwallow Coal. It is a member of the Kanawha Formation
Fossils:
An older term for Lower Ordovician dolomites found in the Champlain Valley of New York and Vermont more usually assigned to the Providence Island Formation. Includes the Weybridge Limestone, Burchards Limestone, Bridport Dolomite and Beldens Limestone.
Fossils: Localized Lower Ordovician marine fossils -- often fragmented
Something over 1000 meters of Proterozoic, Ediacaran and Lower Cambrian shales found in Alabama,Georgia,Maryland,North Carolina, New Jersey, Tennessee, Virginia and West Virginia. Only the uppermost formations -- e.g. Antietam/Harpers Ferry/Helenmode Formation/Cochran Formation/Unicoi Formation are young enough to contain fossils. It overlies Proterozoic metamorphic rocks. is overlain by carbonate rocks Tomstown Dolomite/Shady Dolomite/Maryvale Formation
Fossils: occasional ichnofossils,trilobites,brachiopods, etc in uppermost beds
A Pennsylvanian coal found in West Virginia. It overlies the Dingess Limestone/Lower Mercer Limestone and is probably equivalent to the Fire Clay Coalin Kentucky. It lies above the Whitesburg Coaland below the Hamlin Coal
Fossils: Plants?
40 meters of non-calcerous Middle Devonian black shale found in East Central New York where it overlies the Cherry Valley Limestone or the Otsego Sandstone of the Marcellus Shale. It is overlain by the Cardiff Shale of the Marcellus Formation. It is a member of the Marcellus Formation and occupies part of the interval occupied elsewhere by the Oatka Creek Formationion
Fossils: Few if any
| 2m | Pennsylvanian | coal/shale | WV | Winifrede Shale | Winifrede Shale | Winifrede Coal | fossils:plants | NO GEOLEX link | NO cgkn link |
|---|
Almost 300 meters of gray Early Mississippian shale with minor limestone found in Michigan and Indiana where it overlies the Berea black shale/Sunbury Shale/Ellsworth Shale and is overlain by the Marshall Sandstone
Fossils: Marine invertebrates in the limestones.
Up to 1300 meters of calcaerous marine Middle Ordovician sandstone found in Tennessee and Georgia. It overlies the Tellico Sandstone/Athens Shale/Rockport Slate. It is overlain by the Sevier Shale. It is a member of the Chickamauga Group.
Fossils: Unknown (nothing found in first 30 Google hits)
13 meters of Lower Ordovician dolomite exposed in the Mohawk Valley in the vicinity of Amsterdam, NY. Overlies the Fonda and underlies the Cranesville. All are treated as members of the Tribes Hill formation.
Fossils: TBPL
A thick and confusing series of abundantly fossiliferous Upper Ordovician shales and limestones exposed in a large area centered on Cincinnati, OH. Very numerous names have been used at various times. See the UGA Stratiagraphy Lab pages for comprehensive information on these formations. They overlie the Lexington Limestone and are overlain by the Silurian Brassfield Formation.
Fossils: Abundant and diverse
Fossiliferous Upper Ordovician shale, clay and limestone found in Southwest Ohio, SouthEast Indiana, and adjacent Kentucky. The Clarksville beds overlie the Fort Ancient beds of the Waynesville Formation. They are overlain by the Blanchester member of the Waynesville Formation. They are part of the Richmond Group.
Fossils: Marine invertebrates are common, well preserved, and abundant.
Sparsly fossiliferous cherty crinoidal limestone within the Middle Devonian Onondaga Limestone Group in Western New York where it is roughly equivalent to the Nedrow Limestone limestone further East. The Clarence Limestone overlies the Edgecliff Limestone and is overlain by the Moorehouse Limestone.
Fossils: Sparse
As much as 70 meters of uppermost Middle Ordovician thin bedded limestone and shale found in the area where Kentucky, Indiana, and Ohio meet. It overlies the Lexington Limestone and is overlain by Garrard Siltstone/Kope Formation. The Clays Ferry formation is laterally equivalent to the Point Pleasant Formation/Fairview Formation? and was intended to replace the older Cynthiana Formation/Million Shale terminology for the same beds.
Fossils: Abundant marine fossils including a Triarthus fauna similar to the Utica Shale in New York.
| 107m | Devonian,Lower | limestone,chert | IL,KY,MO | Niagara Group/Backbone/Grassy Knob Chert | Oriskany Sandstones/Grand Tower | fossils:marine invertebrates | GEOLEX link | NO cgkn link | New Harmony |
|---|
Up to 30 meters black shale found primarily in NorthEast Ohio, but also extending to Kentucky, Tennessee, West Virginia, Alabama, Gerogia and Virginia. It overlies the Chagrin Shale/Three Lick Formation. It is overlain by the Sunbury Shale
Fossils: fish in concretions abundant in some beds. Plants. fish and brachiopods in a bed at the top of the formation.
As much as 380 meters of Black River age fossiliferous Middle Ordovician marine limestone found in SouthWest Virginia and adjacent Tennessee. It overlies Beekmantown Age beds and is overlain by the Benbolt Limestone.
Fossils: Marine invertebrates present. Abundance, diversity unclear.
An obsolete(?) term for up to 60 meters of fossiliferous thick bedded limestone with minor clays in West central Tennessee. It overlies the Dyestone Group and is overlain by the Linden Limestone Is equivalent to the Meniscus limestone.
Fossils: sponges, corals
39 meters of thick, gray bedded Mississippian Limestone found in Tennessee. It overlies the Snowflake Formation and is overlain by the Gilliam Creek Limestone. It is laterally equivalent to the St Louis Limestone.
Fossils: Some fossil fragments in some exposures
Up to 30 meters of Upper Silurian/Lower Devonian sandstone and shale found in Virginia and West Virginia. It is a member of the Keyser Limestone and is laterally equivalent to the upper limestone and Big Mountain Shale members.
Fossils: Unknown. Possibly some marine invertebrates.
As much as 90 meters of iron rich Lower Silurian shale and sandstone found in Kentucky,Tennessee,Virginia and West Virginia. It overlies Nashville Formation/Nash Formation/Juniata formation/Sequatchie formation and is overlain by the White Oak Mountain Sandstone/Clinton Group beds.
Fossils: Ichnofossils.
As much as 40 meters of fossiliferous Early to Mid Silurian shales,sandstones,hematites,mudstones and thin limestones found in Kentucky,Maryland,Michigan,New York,Ohio,Ontario,Pennsylvannia,Tennessee,Virginia,and West Virginia. It overlies Lower Silurian Medina Group Sandstones and is overlain by Middle Silurian Lockport Dolomites. The Clinton is subdivided into dozens of thin regional formations.
| Upper Silurian Lockport dolomites | ||
| MIDDLE SILURIAN CLINTON GROUP | ||
| WESTERN NY | CENTRAL NY | MOHAWK VALLEY |
| DeCew Dolomite | Glenmark Shale | |
| Burleigh Hill Shale | Gates Dolomite | Herkimer Sandstone |
| Burleigh Hill Shale | Rochester Shale | Herkimer Sandstone |
| Lewiston Shale | Herkimer Sandstone | |
| Rockway Dolomite | Irondequoit | Kirkland |
| Rockway Dolomite | Irondequoit | Dawes Dolomite |
| Williamson Shale - Willowvale Shale | Westmoreland | |
| Sauquoit Shale | Otsquago | |
| Sodus | ||
| Hickory Corners | Oneida | |
| Neahga Shale | Maplewood Shale-Furnaceville | Oneida |
| Lower Silurian Medina Group | ||
Fossils: TBPL
28 meters of fossiliferous Upper Silurian flaggy limestone found in Northwest New Jersey and adjacent New York where it overlies the Bossardville Limestone and underlies the Rondout Formation. It is a member of the Decker (Decker Ferry) formation and is laterally equivalent to the non-calcaerous Wallpack Center member to its Southwest.
Fossils: abundant - brachiopods, tabulate and rugose corals, crinoid debris, ostracodes, and scattered bryozoans
Fossiliferous Uppermost Silurian Dolomite found in Eastern New York where it overlies Rondout Formation carbonates and is overlain by Lower Devonian formations. Historically, the term was also used in Western New York, Ontario, Michigan, and Ohio for beds now assigned to the Akron and other formations.
Fossils: Stromatoporoids, brachiopods, bivalves
At least 50 meters(??) of highly fossiliferous Middle Ordovician limestones and marls found in SouthEast Ontario. The corresponding rocks in adjaent New York are referred to as the Rust and Steuben formations of the Trenton Group. In the Ottawa area, the corresponding formation is the Eastview Formation. The Cobourg is considered to be the Upper member of the Lindsay Formation in Southern Ontario, the Cobourg is overlain by Blue Mountain Formation Upper Ordovician shales.
Fossils: TBPL
Over 500 meters of Lower Cambrian conglomerate, shale and sandstone found in Alabama, Georgia, North Carolina and Tennessee. It overlies the Sandsuck Shale and is overlain by the Nichols Shale. It is a member of the Chilhowee Group
Fossils: A few ichnofossils
Perhaps 12 meters of fossiliferous Lower Devonian Limestones of the Helderberg Group that overlie the Silurian Cobleskill Dolomites and are overlain by Shaly New Scotland Limestones.
Fossils: TBPL
Up to 14 meters of fossiliferous Middle Ordovician limestone with minor shale found in the Appalachians of Virginia and West Virginia. It overlies the Edinburg Formation and is overlain by the Martinsburg Formation It presumably is the uppermost Ordovician limestone in areas where it is exposed.
Fossils: large corals, probably others
Less than 20 meters of fossiliferous middle Ordovician shales interbedded with thin limestones. Found in Ontario on the Eastern and shore of Lake Huron and the Southern shore of Lake Superior. It overlies Trenton limestones and is overlain by typical Utica shales.
Fossils: TBPL
About 30 meters of fossiliferous Middle Devonian Limestone Found in Ohio, Pennsylvania Ontario and West Virginia. It overlies the Detroit River Group where present and the Onondaga Limestones further East. It corresponds to the Oriskany Sandstone in New York. The Columbus is overlain by the Delaware Limestone #Delaware].
Fossils: Abundant diverse macrofossils especially in the upper parts of the formation. Several regionally persistent bone beds.
Over 1000 meters of sometimes fossiliferous Middle and Upper Cambrian shales and limestones found in Alabama,Georgia,Tennesee,Kentucky,West Virginia and Virginia.. It overlies the Rome Sandstone and is overlain by the Copper Ridge dolomite/Conococheague limestone/Knox Group. Authors differ on which formations should be included in the Group. The following formations are included by one geologist or another -- Bibb Dolomite,Brierfield Dolomite,Copper Ridge Dolomite #CopperRidge],Elbrook Dolomite,Honaker Limestone Limestone,Maryville Limestone,Maynardville Formation,Nolichucky Shale,Pumpkin Valley Shale,Rogersville Shale, and Rutledge Limestone
Fossils: Fairly diverse fossils are found in some beds, especially the Nolichucky Shale.
Over 500 meters of sandy blue Cambrian and Lower Ordovician limestone interbedded with thin sandstones found in Pennsylvannia, Maryland, Tennessee, Virginia, West Virginia. It overlies the Elbrook Dolomite/Buffalo Springs Formation and is overlain by Beekmantown Dolomite/Stonehenge Limestone/Stoufferstown Formation. It is sometimes included in the Knox Group and sometimes treated as a group itself including the Big Spring Station Formation,Snitz Creek Formation, Millbach Formation, Richland Formation, Zullinger Formation, and Shadygrove Formation
Fossils: conodonts, thrombolites, trilobites in a few exposures
| 270m | Pennsylvanian,Middle-Pennsylvanian,Upper | sandstone,shale,limestone,coal | IL,KY,MD,OH,PA,WV | Allegheny/Mahoning | Monongahela | Casselman/Glenshaw | fossils:marine fossils,plants | GEOLEX link | NO cgkn link | Conemaugh | 15 cyclothems |
|---|
Up to 175 meters of fossiliferous(?), marine(?) Upper Devonian siltstones,sandstones,shales, and conglomerate found in Western New York, Northwestern Pennsylvania and Ohio. It overlies similar beds without conglomerate of the Conneaut Group and underlies the Pocono Group or recent sediments. It is subdivided into the conglomerate rich Venango/Cattaragus (130 meters) Formation and the shaly overlying Oswayo (70 meters) Formation.
Fossils: fossils have been reported from the basal conglomerates where present-Spirifera,Pthycopteria. It is unclear whether fossils are present in the higher beds.
| sMississippian, Lower Pocono Group | |
| UPPER DEVONIAN CONEWANGO GROUP | |
| WESTERN NEW YORK | CENTRAL NEW YORK |
| Riceville-Oswayo | Sunfish |
| Cattaragus-Venango | Sunfish |
| Panama Conglomerate, Pope Hollow, Salmanaca, Tunangwant, and Wolf Creek Conglomerate | Sunfish |
| Devonian,Upper Conneaut Group | |
Up to 250 meters of fossiliferous(?), marine(?) Upper Devonian siltstones,sandstones,and shales found in Western New York, Northwestern Pennsylvania and Ohio. It overlies similar beds of the Canadaway Group and underlies the Conewango Group. It is also referred to as the Chadakoin Members include the Chadakoin Formation (NY), Cotton Formation (NY,PA), Cuba Sandstone (NY), Dexterville Formation (NY), Ellicott Shale (NY), Germania Formation (NY,PA), Girard Formation (PA), Rawson Formation (NY), Sunfish Formation (PA), Wellsville Formation (NY), Whitesville Formation (NY).
Fossils: TBPL
| 15m | Pennsylvanian,Lower | sandstone,shales,iron,coal | NY(?),PA,MD,OH*,WV | Sharon | Upper Homewood | fossils:plants in shales | GEOLEX link | NO cgkn link | Pottsville |
|---|
About 11 meters of Lower Devonian marine sandstone and pebble conglomerate exposed in Southern New York and adjacent New Jersey. It is overlain by the Esopus Formation It is considered to be part of the Tristates Group.
Fossils: sparse
| 514m | Ordovician,Lower | limestone | OK | McKenzie Hill Limestone/Strange/Tulip Creek/Wolf Creek? | Alden/Kindblade | fossils: | GEOLEX link | NO cgkn link | Arbuckle |
|---|
Up to 45 meters of reddish Pleistocene sand, gravel and till found in Wisconsin(sc) and possibly Michigan's Northern Peninsula. It is underlain by Paleozoic/Pleistocene beds. It is either the surface formation or overlain by the Miller Creek. It is laterally equivalent to the Horicon Formation.
Fossils: Plant material?, wood?
Up to 800 meters of Uppermost Cambrian and possibly Lower Ordovician cherty marine dolomite or limestone. It overlies the Lower Knox Formation/Nolichucky Shale/Maynardville Limestone in Georgia, Alabama, Mississipi, Tennessee, Kentucky, Ohio, West Virginia and Virginia. It is overlain by the Chepultepec Dolomite/Upper Knox Formation. It is considered to be equivalent of the Conococheague limestone. It is a member of the Knox Group/Beekmantown Group/Conasauga Group/Lee Valley Group.
Fossils: Algal structures. Rarely gastropods.
A nineteenth century term for thin bedded Cambrian Shales and Limestones exposed in Northern Alabama. Probably subsumed into the Conasauga Group in modern usage.
Fossils: Some fossils present?
| 85m | Pennsylvanian,Lower | sandstone,conglomerate | KY,TN | Lee | Irvin/Manchester Coal | Briceville/Sewell/Sharon | fossils: | GEOLEX link | NO cgkn link | Breathitt/Grundy Formation/Lee |
|---|
450 meters of Lower Ordovician dolomite and limestone found in Western Newfoundland to the East of the Lower Ordovician St George Group It overlies the Hughes Brook Formation and is possibly overlain by the Table Head Group.
Fossils: some marine invertebrates in the limestones
An obselete 19th century term for widespread limestones found at the base of the Middle Devonian sequence in New York and adjacent states. Corresponds roughly to the modern Onondaga Group.
Fossils: Abundant, diverse, Middle Devonian marine fossils
About 12 meters of gray fissile Upper Devonian shale and siltstone found in New York and Pennsylvania It overlies the Meads Creek Shale is overlain by the New Milford Formation. It is a member of the Gardeau Formation
Fossils: Unknown: Probably few or none
Up to 3 meters of coarse grained Middle Ordovician limestone found in Kentucky. It overlies the Perryville limestone/Salvisa Limestone and is the topmost member of the Lexington Limestone in some areas. It is overlain by the Greendale Formation/Brannon Limestone. Some authors consider the Cornishville to be a member/bed in the Perryville Limestone.
Fossils: brachiopods,bryozoa,stromatoporoids
About 20 meters of fossiliferous Upper Ordovician marine thin bedded limestone and shale found in Southwest Ohio and adjacent Kentucky. It overlies the Bellevue Limestone and is overlain by the Mt Auburn/Straight Creek. It is a member of the McMillan Formation/Grant Lake. It is a part of the Cincinnati Group.
Fossils: Chiloporella
Up to 160 meters of granular Lower Ordovician cherty dolomite found in Arkansas,Missouri,and Illinois. It overlies the Jefferson City Limestone and is overlain by the Powell Limestone.
Fossils: rare, but gastropods, cephalopods, and reef building algae have been reported
An upper Devonian marine formation found in North Central Pennsylvannia. It is a member of the Conneaut Group. Essentially no information available
Fossils: TBPL
One or two one meter thick layers of fossiliferous Lower Permian limestone found in Oklahoma, Kansas, Nebraska. It overlies the Eskridge Shale and is overlain by the Florena Shale which was called the Cottonwood Shale in some early papers. It is a member of the Beattie Limestone/Council Grove Group/Oscar Group
Fossils: Marine Invertebrates
50 meters of marine Lower Permian cyclically deposited shales and limestones found in Oklahoma, Kansas and Nebraska. It overlies the Wabaunsee Group/Admire Group and underlies the Chase Group. It includes the Foraker Limestone/Cottonwood Limestone,Johnson Shale,Red Eagle Limestone,Roca Shale,Grenola Limestone,Eskridge Shale/Florena Shale,Beattie Limestone/Morrill Limestone,Stearns Shale,Bader Limestone,Easly Creek Shale,Crouse Limestone,Blue Rapids Shale,Funston Limestone,Speiser Shale,Garrison Formation
Fossils: often abundant marine invertebrates in both the shales and limestones.
About 350 meters of Upper Mississippian limestone and sandstone found in Tennessee(ne) and Virginia. It overlies the Fido Sandstone and is overlain by the Pennington Shale
Fossils: Mostly sparse except for a bed of marine fossils at the base.
Unfossiliferous Upper Cambrian conglomerates and sandstones found at Covey Hill and along the English(Anglais) River in Ontario and Western Quebec. It is regarded as a Potsdam Formation equivalent. The Covey Hill Formation is overlain by the Cairnside Formation.
Fossils: TBPL
Up to 13 meters of varicolored Early to Middle Silurian shale with minor limestones found in east central Kentucky and Ohio. It overlies Medina age sandstones/Brassfield Limestones and is overlain by Devonian limestones/Bisher Formation. It is sometimes subdivided into *Indian Fields Formation* and Alger formations or Noland Formation and Estill Shale.
Fossils: marine invertebrates in the limestones and dolomites
An almost entirely unfossiliferous Lower Ordovician dolomite exposed in the Mohawk Valley in the vicinity of Cransville, NY. Overlies the Chuctanunda Creek Formation. It may be considered to be a member of the Tribes Hill formation. It is the uppermost of the Lower Ordovician formations in the Mohawk Valley and unconformally underlies Middle Ordovician limestones.
Fossils: TBPL
3 to 4 meters of Permian limestone,shale,and chert found in Kansas(e), Nebraska(se), and possibly Iowa. It overlies the Grant Shale and is overlain by the Odell Shale/Luta Limestone. It is a member of the Winfield Limestone of the Chase Group
Fossils: Marine Invertebrates - echinoid spines, bryozoans, and brachiopods
4 meters of Permian limestone divided by a shale found in Oklahoma, Kansas(e) and Nebraska(se). It overlies the Easly Creek Shale and is overlain by the Blue Rapids Shale. It is a member of the Council Grove Group/Oscar Group
Fossils: Marine Invertebrates
Fossiliferous early Middle Ordovician limestones found in the Champlain Valley of New York and Vermont. It is the middle member of the Chazy Limetone. It overlies the Day Point member of the Chazy Group. It is overlain by the Valcour Limestone member of the Chazy Group
Fossils: Diverse fossils often not easily distinguishable in the massive limestones. The large gastropod Maclurites is abundant in some beds
| 43m | Pennsylvanian,Middle | shale,siltstone,limestone,sandstone | KY,WV | Lower Elkhorn Coal/Upper St Charles Coal | Upper Elkhorn Coal/Kelly Coal | Cannelton Limestone/Wise Formation | fossils:marine invertebrates | GEOLEX link | NO cgkn link | Breathitt Formation/Pottsville/Pikeville Formation |
|---|
15 meters of pure Upper Ordovician or Silurian sandstone found in SouthEast Missouri where it overlies the Potosi Dolomite/St Francois Limestone and is overlain by the Joachim Limestone Equivalent to the St Peter Sandstone
Fossils: A few ichnofossils?
Fossiliferous Upper Devonian marine sandstones interbedded with shales found in Western New York at the Stratiagraphic level of the top of the Canadaway Group and the bottom of the Conneaut Group. The Cuba formation overlies the lithogically similar Machias Formation and is overlain by the Wellsville Formation].
Fossils: brachiopods and crinoid fragments in coquina beds. Ichnofossils
Sparsely fossiliferous Middle Ordovician shales and limestones lying between the limestones of the Orwell formation and the shales of the Stony Point formation in the Champlain Valley of Vermont and New York.
Fossils: TBPL
10 meters of fossiliferous, cherty Middle Ordovician limestone found in Indiana,Kentucky,Ohio and Tennessee. It is regarded as a member of the Lexington Limestone in Kentucky and of the Hermitage Limestone in Tennessee. It overlies the Tyrone Limestone/Carters Limestone and is overlain by the Logana Limestone
Fossils: abundant marine invertebrates-brachiopods, bryozoans, mollusks, trilobites, corals, crinoids, and ostracodes
Fairly thin Upper Devonian and Lowest Mississippian marine sandstones found in Pennsylvania, West Virgina and Ohio. It overlies Riceville Shales and is overlain by the Bedford Shale.
Fossils: Enough brachiopods to permit dating. Marien fossils might be fairly abundant.
Up to 50 meters of fossiliferous Middle Ordovician limestone with some shale found in Kentucky, Southwest Ohio and possibly Indiana. In keeping with tradition, the nomenclature for these beds is enormously confused. Some authors treat the Cynthiana as having an upper Point Pleasant member and a lower Greendale member. Others percieve a number of members Greendale/Nicholas/Rogers Gap/Gratz Shale /Bromley/Millersburg/Sulphur Well/Woodburn The Cynthiana overlies the Lexington Limestone/Perryville/Cornishville and is overlain by the Kope Formation/Fulton Shale/Eden Group. The faunas of the upper Cynthiana are Utica age and are identical to the overlying Upper Ordovician beds. The Cynthiana has been assigned by various authors to the Lexington Limestone and Eden group, but is usually treated as an independent entity.
Fossils: Moderately fossiliferous with diverse, well preserved, Ordovician marine fossils.
About 50 meters of Upper Mississippian sandstone with minor shale, coal, and limestone found in Alabama,Illinois,Indiana,Kentucky,Tennessee,and Missouri. It overlies the St Genevieve limestone/Gasper Limestone/Paint Creek Formation/Ridenhower Formation/Reelsville Formation and is overlain by the Tribune limestone/Golconda Formation/Pride Mountain Formation/Beech Creek Limestone. It is a member of the West Baden Group
Fossils: Marine invertebrates in the limestones. Plants in/near coal beds
Upper Devonian redbed shales the Catskill Group found in NorthEastern Pennsylvania and adjacent New York. They overlie the Honesdale Sandstone or Cherry Ridge Formation and are overlain by the Pocono Sandstone.
Fossils: Unknown
1100m or more of Middle Ordovician marine Martinsburg black shale/slate found in South Central and East Central Pennsylvania. It overlies the Chambersburg Limestone/Jacksonburg Limestone and is overlain by the Fairview Sandstone/Shochary Sandstone.
Fossils: None? Sparse at best
Roughly 30 meters of bluish Upper Cambrian calcaerous shale with thin limestone and dolomite beds found in Illinois, Indiana, Kansas, Minnesota, Missouri and Oklahoma. It overlies the Bonneterre Formation and is overlain by Derby Dolomite. In various regions, it is treated as a member of the Elvins Group, Munising Group or the Franconia Formation.
Fossils: Enrolled trilobites have been reported from some beds in Missouri.
About 3 meters of unfossiliferous slightly calcaerous Lower Silurian sandstone found in North Central New York. It is member of the Clinton Group #Clinton]. It overlies the Willowvale Shale and is overlain by the Kirkland Hemitite.
Fossils: None
Up to 80 meters of Fossiliferous early Middle Ordovician sandstones, siltstones, limestones found in the Champlain Valley of New York and Vermont. It is the oldest member of the Chazy Limetone. It overlies Lower Ordovician Providence Island Formation or Bridport Dolomite beds of the Beekmantown rocks and is overlain by the Crown Point Limestone of the Chazy Group.
Fossils: Varies with the beds exposed -- brachiopods, bryozoa, trilobites, corals.
A Middle Silurian dolomite/limestone found in Kentucky, Indiana and Ohio. Up to 15 meters but usually much less of thin, even bedded limestone and marl. It overlies Clinton Age beds/Brassfield Limestone/Noland Formation/Drowning Creek Formation/Lulbegrud Shale and is overlain by the Alger Formation/Osgood Shale/Estill Shale
Fossils: Uncommon. A few corals, cephalopods, etc
A Cambrian Sandstone/Quartzite found primarily in the Northwestern Great Plains. See WCPALEO.HTM
One to four meters of sandy Early Silurian limestone with interbedded shale found at the base of the Lockport Dolomite where it overlies the Rochester Shale of the Clinton Group. It is overlain by the Gasport Dolomite. It is found in the Niagara region of New York and Ontario.
Fossils: Conodonts only?
23 meters of interbedded Upper Silurian sandstone, siltstone, limestone, and dolomite found near the junction of New York, New Jersey, and Pennsylvania. It consists of a more calcaerous Clove Brook Member and a sandier Wallpack Center member The Decker/Decker Ferry overlies the Bossardville Limestone and is overlain by the Rondout Formation
Fossils: Ostracods. Abundant, but poorly preserved, casts and molds in the sandstones.
Up to 30 meters of Middle Ordovician calcaerous green shale with limestones found in Iowa, Illinois, Minnesota, Missouri, and Wisconsin. It overlies the Platteville Limestone/Plattin Limestone and is overlain by the Galena Limestone/Kimmswick Limestone. It is subdivided into a Sprechts Ferry member,(A Kings Lake member), a Guttenberg member and a (Ion member)
Fossils: abundant brachiopods, corals, gastropods, bryozoa
| 8m | Pennsylvanian,Upper | limestone,shale | IA,KS,MO,NE | Tecumseh Shale | Calhoun Shale | fossils:? | GEOLEX link | NO cgkn link | Shawnee |
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About 15 meters of white Middle Ordovician silty dolomite and limestone found in Missouri and Illinois. It is a member of the Joachim Formation.
Fossils: stromatolites
About 10 meters of fossiliferous Middle Devonian Limestone Found in Ohio and Pennsylvania where it overlies the Columbus Limestone and is overlain by Ohio Black Shales Early geologists almost certainly equated it to the substantially older Onondaga Limestones and equated the overlying shales (again probably incorrectly) to the Marcellus Shale
Fossils: Bone beds. Invertebrates?
400 meters or more of flaggy Upper Devonian shales found along the Delaware River near the boundary between New York and Pennsylvania. The Delaware River Flags are a member of the Catskill Group and overlie the New Milford Sandstones Modern usage seems to be to include the overlying Shohola Shales and Lackawaxen Conglomerates as members within the Delaware River Formation.
Fossils: Plant fossils have been reported at several localities in New York North of Port Jervis.
Up to 60 meters of highly fossiliferous Middle Ordovician limestones and marls divided into a lower Poland member and and upper Russia member. But other members have been defined. Also called the Denmark formation. The nomenclature of beds in the Upper Trenton Group is complex, overlapping, and confusing. For the most part it overlies the Sugar River formation and is overlain by the Rust formation. The Denley is found the the Southwest, west and North of the Adirondack mountains of New York and adjacent Ontario. To the SouthEast, it thins and eventually transitions into black "Utica Shales".
Fossils: TBPL
Roughly 15 meters of silty Upper Cambrian dolomite found in Missouri,and Illinois. It may be much thicker in some parts of Missouri. It overlies the Davis Formation and is overlain by the the similar Doe Run Dolomite. It is a member of the Elvins Group and is laterally equivalent to the Franconia Formation.
Fossils: Stromatolites and trilobites(?)
About 170 meters of Middle Devonian limestone and dolomite found in SouthEastern Michigan, adjacent Ontario and NorthWestern Ohio. It overlies the Sylvania sandstone or older formations and is overlain by various formations. It is divided into the Flat Rock dolomite, Anderdon limestone, Amherstburg dolomite, and Lucas dolomite
Fossils: Said to contain marine fossils locally, but probably not too abundant as its age was somewhat controversial even in the 1990s, implying an absence of index fossils.
2 to 4 meters of Lower Silurian marine white quartzitic sandstone with some dolomitic sand layers and minor shale interbeds. Further West, it interfingers with a western facies called the Balls Falls Sandstone of the Medina Group. It is found in Western New York and adjacent Ontario It overlies the Power Glen Shale and is overlain by the Grimsby Sandstone. The name conflicts with the younger and now abandoned Devils Hole Dolomite
Fossils: Unknown
Middle Silurian fossiliferous marine dolomite of the Lockport Group. It is found in Western New York and adjacent Ontario It overlies the Eramosa Dolomite and is overlain by the Oakfield Limestone. The name was proposed to get around a name conflict with Lower Shelby Formation was abandoned because it conflicts with the older Devils Hole Sandstone of the Medina Group
Fossils: Marine invertebrates reported. No further details
8 meters of Middle Ordovician Limestone found in Kentucky. It overlies the Tanglewood Limestone and is overlain by the Millersburg Formation. It is laterally equivalent to the upper Tanglewood Limestone. It is a member of the Cynthiana Formation/Lexington Limestone.
Fossils: Gastropods, brachiopods, ostracods
Fossiiferous Upper Devonian marine sandstones and shales found in Western New York and adjacent Pennsylvania. It is a member of the Conneaut Group. It overlies the Canadaway Group and is overlain by the Ellicott Formation.
Fossils: Contains reasonably abundant marine fossils - Brachiopods,bivalves,etc.
100 meters or more of fossiliferous Upper Ordovician limestone and shale found in SouthEast Indiana. It overlies the Kope Formation and underlies the Saluda Formation Dillsboro Formation of Maquoketa Group The Dillsboro is equivalent to the Mount Hope, Fairmount, Bellevue, Corryville, Mount Auburn, Arnheim, Waynesville, and Liberty formations as well as the Bull Fork.
Fossils: abundant, diverse, marine invertebrates
| 24m | Pennsylvanian,Middle | limestone,shale,sandstone | WV | Williamson Coal | ? | Breathitt Formation | fossils:marine invertebrates | GEOLEX link | NO cgkn link | Kanawha Formation |
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| 149m | Pennsylvanian,Lower | sandstone,shale,coal,conglomerate | VA/WV | Council Sandstone | McClure Sandstone | fossils: | GEOLEX link | NO cgkn link |
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Up to 25 meters of Middle Silurian red or gray calcaerous clay found in Tennessee. It overlies the Lego Formation and is overlain by the Brownsport Formation/Pegram Formation/Chattanooga Shale. It is laterally equivalent to the Mocassin Springs Formation and the Wabash Formation.It is a member of the Wayne Groupe
Fossils: Some marine invertebrates.
About 2.5 meters of Middle Devonian clay found in Eastern Lower Michigan. It overlies the Alpena Limestone and is overlain by the Norway Point Formation. It is a member of the Four Mile Dam Formation of the Traverse Group
Fossils: Crinoids, ostracods, edrioasteroids, chitinizoa.
Roughly 20 meters of silty Upper Cambrian/Lower Ordovician dolomite found in Kansas,Missouri,and Illinois. It may be much thicker in some parts of Missouri. It overlies the similar Derby Dolomite and is overlain by the Potosi Dolomite/[Eminance Dolomite[#Eminence]. It is laterally equivalent to the Franconia Formation.
Fossils: Brachiopods, crinoids. Stromatolites(?), Trilobites(?) Not clear how common
As much as 10 meters(?) of interbedded Middle Ordovician limestones and shale that replaces the lower part of the Denley formation in parts of the Mohawk Valley to the South and East of West Canada Creek. It is always overlain by black "Utica Shales" and may overlie either the lower members of the Trenton limestone or, further East, "Utica Shales". Some authors may have used the term in Ontario
Fossils: TBPL
Up to 60 meters of red,yellow, or gray Middle Ordovician limestone and dolomite found in Tennessee and Virginia. It overlies the Mascot dolomite and is overlain by the Poteet limestone.
Fossils: Unknown
about 20 meters of varicolored Lower Permian shales with minor limestones found in Oklahoma?, Kansas(e), and Nebraska(se). It overlies the Fort Riley limestone and is overlain by the Winfield Formation. It is subdivided into the Holmesville shale, Towanda Limestone, and Gage Shale It is a member of the Chase Group/Oscar Group
Fossils: A few marine invertebrates in the shales at the top of the formation
Up to 30 meters of sparsely fossiliferous Upper Ordovician limestone and dolomite with some calcaerous clay found in Southwest Ohio, Indiana, and Kentucky. The Drakes overlies the Ashlock Formation/Grant Lake Formation/Bull Fork Formation. It is overlain by the Brassfield Limestone. The Drakes Formation has been subdivided into Preachersville, Rowland, Bardstown, and Saluda members. It is the youngest member of the Richmond Group
Fossils: Marine invertebrates -- brachiopods and bryozoa present, but not too common and none too well preserved
An Upper Cambrian shale and sandstone recognized in Iowa, Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin. It overlies the Eau Claire Sandstone and is overlain by the Franconia Sandstone. Its fossil faunas are a reference fauna for the North American Upper Cambrian. Modern usage is probably to treat the Dresbach and Franconia as biostratigraphical units. The lithology based unit corresponding to the Dresbach is the lower portion of the Elk Mound Group
Fossils: Present in some beds.
Up to 20 meters of Lower and Middle Silurian dolomite,limestone,shale and chert. It is found in Kentucky,Virginia,and West Virginia It overlies the Preachersville Formation/Juniata Formation and is overlain by the Lulbegrud Shale. It is subdivided into the Brassfield Limestone, Plum Creek Shale and Dayton Dolomite/Oldham members. It is a member of the Crab Orchard Group
Fossils: Some marine invertebrates in the lower part of the formation.
About 13 meters of fossiliferous Upper Ordovician dolomite with shale partings found in Iowa,Illinois,Minnesota,Wisconsin. It overlies the Stewartville Formation and is overlain by the Maquoketa Formation A member of the Galena Group
Fossils: algae, receptaculids, diverse marine invertebrates
Roughly 400 meters of interbedded gray and red Upper Devonian sandstones,siltstones and shales found in a relatively small area in SouthEastern Pennsylvania. It is a member of the Catskill Formation
Fossils: ichnofossils, some fish fragments
33 to 53 meters of fossiliferous Middle Devonian Limestone found in SouthEast Michigan and Adjacent Ohio and Indiana. It overlies the Lucas Formation and is overlain by the Traverse Group/Silica Shale.
Fossils: Largely unfossiliferous, but conodonts and shell beds have been reported.
As much as 30 meters(?) of unfossiliferous black marine Upper Devonian Shale with calcaerous nodules found in New York, Ohio, Pennsylvania, West Virginia and Virginia. The Dunkirk is a member of the Canadaway Group in New York and of the Perrysburg Group or Chattanooga Group in other states. In Ohio, it corresponds to the Huron Shale. In New York, it overlies, the West Falls Group and is overlain by the Gowanda Formation.
Fossils: Basically unfossiliferous: A few Conodonts and small plant fragments in some outcrops
Probably Lower Permian limestone found in Kansas where it overlies a shale bed Elmdale Shale? above the Americus Limestone. Might be equivalent to the Neva Limestone? Not to be confused with the Mesozoic Dunlap Formation found in Nevada.
Fossils: Marine Invertebrates probably present
Up to 120 meters of Middle and Upper Ordovician marine dolomite with green shale partings found in Iowa, Illinois, Minnesota, Missouri and Wisconsin. It is overlies the Decorah Formation and is overlain by the Wise Lake Formation It is a member of the Galena Group
Fossils: Receptaculites, other marine invertebrates.
Up to 60 meters of dirty Middle Ordovician limestone and dolomite found in Arkansas, Illinois, Indiana, and Missouri. It overlies the St Peter Sandstone and is overlain by the Joachim Dolomite.
Fossils: Stromatolites, pelecypods, gastropods, brachiopods, ostracods, and conodonts
A nineteenth century term for about 100 meters of Middle Silurian, Clinton Age sandstone, shale and hematite beds found in Tennessee. It overlies the White Oak Mountain Sandstone and is overlain by carboniferous shales.
Fossils: Present
Four meters of gray Permian marine? shale and gypsum found in Kansas(e) and Nebraska(se). It overlies the Middleburg Limestone and is overlain by the Crouse Limestone. It is a member of the Council Grove Group
Fossils: None?
Dark, Calcaerous Ordovician shale found in Quebec(w). It overlies the Ottawa Limestone and is overlain by the Billings Shale. It is a member of the Lindsay Formation. It is laterally equivalent to the Cobourg Formation.
Fossils: Triarthus fauna
About 15 meters of Pennsylvanian lagoonal sandstone found in the Grand River Area of South Central Lower Michigan. It overlies the Saginaw Group and is overlain by recent glacial debris. Its relationship to the Ionia and Woodville Sandstones is unknown. It is a member of the Grand River Group
Fossils: Plants, invertebrates, ichnofossils
30 meters of Upper Cambrian sandstone with interbedded fossiliferous shales and siltstones found in Iowa,Illinois,Indiana,Michigan,Minnesota,Missouri,and Wisconsin. It overlies the Mount Simon Sandstone/Galesville Sandstone/Jacobsville Sandstone and is overlain by Dresbach Shale/Wonebac Formation. It is a member of the Munising Group/Elk Mound Group. It is laterally equivalent to the Conasauga Shale/Bonneterre Formation
Fossils: ichnofossils,trilobites,brachiopods
A somewhat obsolete term for fossiliferous, calcaerous Upper Ordovician Shale and limestone found in Southwest Ohio as well as adjacent Indiana and Kentucky. It overlies the Fulton Shale. It is overlain by the Southgate Shale. In modern usage, it is in the Kope Formation/Latonia formation. It is a member of the Cincinnati Group
Fossils: Abundant, well preserved, Upper Ordovician fossils - Bryozoa,Brachiopods,crinoids,trilobites-Cryptolithus
A quasi-obsolete term for 80 meters or moreof fossiliferous Upper Ordovician shales with minor limestones found in the Cincinnati area of Ohio, Kentucky and Indiana. It overlies the Lexington Limestone/Cynthiana Group and is overlain by the Maysville Group. The Eden's four subdivisions were distinguished on a biostratigraphical basis that proved to be difficult to translate to areas distant from Cincinnati. The Economy, Southgate, McMicken and Fulton, were generally recognized within the Eden which is roughly equivalent to the modern Kope Formation. The term Eden is used in various contexts over an area extending from Alabama to West Virginia to Indiana.
Fossils: Moderately fossiliferous with diverse, well preserved, Ordovician marine fossils.
Up to 10 meters of fossiliferous, massive, sometimes cherty Middle Devonian Limestone found above Tristates Group clastics across Northern New York. It is member of the Onondaga Group.
Fossils: TBPL
Up to 1400 meters of fossiliferous Middle and Upper Ordovician cobbly Limestone and black shale found in Virginia and West Virginia. The Edinburg overlies the Lincolnshire Limestone [#Lincolnshire]. It is overlain by the (Oranda Formation)/Collierstown Limestone/Martinsburg Shales/Reedsville Formation. It has been divided into Botetourt, Lantz Mills, Liberty Hall, and St Luke members.
Fossils: Ordovician marine invertebrates -- conodonts, Mastopora, Receptaculites, Cryptophragmus, bryozoa, brachiopods
About 3 meters of Lower Permian limestone found in Kansas(e) and Nebraska(se). It overlies the Stearns Shale and is overlain by the Easly Creek Shale. It is a member of the Bader Limestone of the Council Grove Group
Fossils: Abundant Marine Invertebrates
50 meters of thin bedded Middle Ordovician limestone found in Virginia, West Virginia,Tennessee,and Kentucky. It overlies the Hardy Creek Limestone/Moccasin Formation/Witten Limestone. It is overlain by the Trenton Limestone/Martinsburg Shale.
Fossils: Diverse and moderately abundant
Up to 1000 meters of Middle and Upper Cambrian limestone and dolomite with red and green shales found in Maryland, Pennsylvania, Tennessee, Virginia and West Virginia. Overlies the Waynesboro Formation/Honaker Dolomite/Rome Formation and is overlain by the Knox Limestone/Conococheague limestone/Nolichucky Shale.
Fossils: Not especially common. stromatolites, trilobites reported from the basal limestones at some localities.
up to 15 meters of Upper Ordovician shale and minor limestones found in Southwest Ohio, and Indiana. The Elkforn overlies the Whitewater Formation/Saluda Limestone/Drakes Formation. It is overlain by the Brassfield Limestone. It is a member of the Richmond Group.
Fossils: Marine invertebrates are common, well preserved, and abundant.
Up to 200 meters of Upper Cambrian sandstones and shale found in Wisconsin. It ovelies precambrian rocks and is overlain by the Tunnel City Group It includes the Mount Simon Sandstone,Eau Claire Formation and Wonewoc Formation which are based on lithology rather than biostratigraphy. The Mount Simon Sandstone and Eau Claire Formation correspond to the Dresbach and the Wonewoc Formation corresponds to the Ironton Member of the Franconia.
Fossils: Apparently present and distinctive enough for biostratigraphic dating.
about 50 meters of Upper Devonian marine shales found in Western New York and adjacent Pennsylvania. It is a member of the Conneaut Group. It overlies the Dexterville Formation and is overlain by the Ellicott Formation.
Fossils: Contains marine fossils - Brachiopods,bivalves,etc.
150 meters of gray and green Upper Devonian and Lower Mississippian shale found in Michigan and Indiana. It overlies the Antrim Shale and is overlain by the Sanilac Formation/Sunbury Shale/Coldwater Shale
Fossils: Algae, conodonts
An obsolete term for 40 meters of Pennsylvanian shale and limestone found in Oklahoma,Nebraska,and Kansas. It overlies the Americus Limestone and is overlain by the Neva Limestone. It is a member of the Wabaunsee Group
Fossils: Fairly abundant marine invertebrates in both the shales and limestones-- fusulinids
About 40 meters of Upper Cambrian shale dolomites, and shaly limestones found in Iowa and Missouri. It overlies the Bonneterre Limestone and is overlain by the Potosi Group.
Fossils: A few brachiopods and cystoid stems.
Up to 30 meters of sometimes shaly or cherty Middle Ordovician limestone found in Tennessee, Virginia and West Virginia. The Elway overlies the Blackford Limestone and is overlain by the Five Oaks Limestone. It is a member of the Lurich Formation
Fossils: Present. Possibly abundant in some beds, but overall abundance is not known.
About 15 meters of Upper Mississippian shale, siltstone and sandstone found in Indiana and Kentucky It overlies the Reelsville Limestone/Sample Formation and is overlain by the Beech Creek Limestone/Mansfield Formation. It is laterally equivalent to the Cypress Formation and is a member of the West Baden Group
Fossils: Present? Abundance unknown. Some well preserved blastoids are cited.
2 meters or less of gray marine Upper Pennsylvanian limestone found in Iowa, Kansas(se), Nebraska, Missouri, and Oklahoma. It overlies the Harveyville Shale and is overlain by the Willard Shale It is a member of the Emporia Limestone/Wabaunsee Group/Vanoss Group
Fossils: Marine invertebrates and fragments
Up to 80 meters of cherty Upper Cambrian/Lower Ordovician dolomite found in Arkansas,Missouri,and Illinois and (subsurface only) also in Oklahoma, Kansas, and Colorado. It overlies the Potosi Dolomite/Bonneterre Dolomite and is overlain by the Gunter Sandstone/Proctor Limestone/Gasconade Dolomite/Oneota Dolomite. It is considered to be a member of the Arbuckle Group in the Western exposures and the Knox Group to the North and East. It includes the Momence Sandstone and is laterally equivalent to the Jordan Sandstone.
Fossils: generally sparse due to dolomotization(?) but gastropods(?) may be found in some cherty layers.
Two beds of Upper Pennsylvanian limestone sith an intermediate shale found in Iowa(sw), Kansas(e), Missouri(nw), Oklahoma and Nebraska(se). It is divided into the Reading limestone, Harveyville shale, and Elmont limestone. It overlies the Olpe Shales and is overlain by the Admire Shales It is a member of the Wabaunsee Group/Vanoss Group
Fossils: Marine Invertebrates fairly abundant - gastropods
Upper Devonian shales and sandstones found in the Sonyea Group in Central New York that grade westward into finer grained shales of the Middlesex Formation and Cashaqua Formation. It overlies the Genesee Group and is overlain by the Rye Point Formation.
Fossils: fish fragments. Others?
An obsolete term for 12 meters of Lower Permian shale found in Kansas(e) and Nebraska(se) that overlies the Luta Limestone/Cresswell Limestone and is overlain by the Herington Limestone.
Missing Formations:
Fossils: marine invertebrates-bivalves
15 meters of fossiliferous Upper Silurian dolomite found Western New York and adjacent Ontario. The Eramosa is overlies the Goat Island Dolomite and is overlain by the Devils Hole Dolomite or Guelph Dolomite. Thought to be a Western equivalent of the Sconondoa Dolomite of the Lockport Group
Fossils: poorly preserved corals, stromatoporoids and stromatolites
200 meters or more of Lower Cambrian quartzite,sandstone capped with shale found in Tennessee, North Carolina, and Virginia. Overlies the Hampton Shale and is overlain by the Shady Limestone
Fossils: trilobites in the upper shale. Ichnofossils
Up to 13 meters of Upper Pennsylvanian shale and limestone found in Oklahoma, Kansas(e), Nebraska(se). It overlies the Neva Limestone and is overlain by the Cottonwood Limestone. It is a member of the Council grove Group/Oscar Group
Fossils: Marine Invertebrates
As much as 100 meters(?) of fossiliferous Lower Devonian shale, sandstone or slate found in Eastern New York and adjacent New Jersey and Pennsylvania. It overlies Oriskany formation sandstones or equivalent limestones and is overlain by Lower Devonian Sandstone units.
Fossils: Abundant Zoophycus. Other fossils are diverse, but not terribly common except at a locality in Highland Mills, NY
25 meters or more of green Middle Silurian shale with minor limestones/dolostones found in Kentucky and Ohio. It overlies the Waco Limestone/Noland Formation/Dayton Formation and is overlain by the Bisher Formation. It is a member of the Crab Orchard Group/Alger Shale
Fossils: Sparse in the lower parts of the formation. 22 species of megafossils reported in the upper beds.
Up to 200 meters of Lowest Middle Ordovician heterogenous rocks including dolomite, limestone, sandstone, and shale found in Arkansas,Missouri,Illinois,Indiana,and Tennessee. It overlies the Powell Dolomite and is overlain by the Saint Peter Sandstone.
Fossils: uncommon, but ostracods, cephalopods, gastropods, bivalves, trilobites, and bryozoans have been found
25 meters of Upper Ordovician Limestone with minor shale found in Ohio(sw) and Indiana(se). It overlies the Bellevue and is overlain by the Mount Auburn It is considered to be the upper member of the Fairview Formation
Fossils: diverse and abundant - brachiopods, etc
Up to 35 meters of Upper Ordovician Limestone and calcaerous shale found in Southwest Ohio and adjacent Indiana and Kentucky. It overlies the Kope Formation It is overlain by the Grant Lake Limestone/McMillan Formation/Miamitown Shale The lower part is sometimes identified as the Mt Eden Formation. It is a member of the Cincinnati Group The "Hilltop Quarries" cited by the 19th Century workers were small dimension stone quarries in the Fairview near the top of low hills West of downtown Cincinnati.
Fossils: Abundant, diverse, well preserved Upper Ordovician fossils
2 meters or more of fossiliferous Lower Permian limestone found in Nebraska(se) and Kansas(e). It overlies the Aspinwall Shale/Hawxby Shale and is overlain by the West Branch Shale. It is a member of the Admire Group
Fossils: abundant bivalves, bryozoa, a few brachiopods
About 50 meters of Upper Mississippian black (mostly) shale with some limestone sometimes found in Arkansas,Missouri,and Oklahoma. It overlies the Wyman Sandstone/Grand River Limestone/Hindsville Limestone/Batesville Sandstone and is overlain by the Wedington Sandstone/Pitkin Limestone/Hale Limestone.
Fossils: Locally rich in brachiopods
At least 6 meters of Middle Devonian limestone and shale found in Michigan. Overlies the Rockport Quarry Limestone and is overlain by the Genshaw Formation. It is member of Traverse Group
Fossils: Abundant marine invertebrates - corals,brachiopods,bryozoa, etc
12 or so meters of fossiliferous Upper Ordovician shale and limestone found in Alabama,Arkansas,Georgia,Oklahoma,Tennessee,Missouri and Illinois. The Fernvale overlies the Leipers Formation/Arnheim Formation and is overlain by the Clifton Formation/Sequatchie Formation.
Fossils: Marine invertebrates.
Up to 25 meters of reddish Upper Mississippian calcaerous sandstone found in Tennessee and West Virginia. Overlies the Fisher Creek Limestone/Greenbrier Limestone and underlies the Cove Creek Limestone.
Fossils: brachiopods, trace fossils
450 meters of Mississippian sandstone and limestone found in Kentucky(ne). It overlies the Gilliam Creek Limestone and is overlain by the Fido Sandstone
Fossils: Unknown
15 meters of Middle Ordovician Limestone found in Virginia, Tennessee, and West Virginia. It overlies the Blackford Limestone/Elway Limestone. It is overlain by the Ward Cove Limestone/Lincolnshire Limestone/Peery Limestone. It is a member of the Cliffield Limestone/Lurich Group.
Fossils: Probably Chazy age marine invertebrates.
1.3 meters of fossiliferous Lower Permian marine limestone found in Oklahoma, Kansas(e), and Nebraska(se). It overlies the West Branch Shale and is overlain by the Hamlin Shale It is a member of the Janesville Shale/Admire Group/Vanoss Group
Fossils: fusulinids, brachiopods, bryozoans, horn corals, and crinoids.
Up to 13 meters of Middle Ordovician chert found in Kentucky(nc). It Overlies the Lexington Limestone and is overlain by the Winchester/Bromley/Million Formations.
Fossils: Probably present and possibly abundant
88 meters of Black Middle Ordovician Utica Shale found in the Mohawk Valley of New York where the Utica Shales are divided into two formations by the intervening Dolgeville Limestone. The Flat Creek member overlies Trenton age Glenn Falls Limestones. The [#Canajoharie shales ##Canajoharie] of older publications may be equivalent to the Flat Creek
Fossils: TBPL
Up to 50 meters of Middle Devonian Dolomite found in SouthEast Michigan and adjacent Ohio and Ontario. It overlies the Sylvania Sandstone and is overlain by the Anderdon Limestone. It is the lowermost member of the Detroit River Group
Fossils: Sparse
Up to 4 meters of fossiliferous Lower Permian shale found in Oklahoma,Kansas,and Nebraska. It was called the Cottonwood Shale in some early papers. It overlies the Cottonwood Limestone and is overlain by the Morrill Limestone It is a member of the Beattie Limestone of the Council Grove Group/Oscar Group
Fossils: brachiopods (and other marine invertebrates?)
7 meters of fossiliferous Permian limestone with prominent chert layers found in Oklahoma, Kansas, and Nebraska. It overlies the Blue Springs Shale and is overlain by the Fort Riley Limestone There are other Florence formations in Wisconsin, Vermont, and as an obsolete name for the Fort Riley Limestone in Kansas. It is a member of the Chase Group/Oscar Group
Fossils: abundant brachiopods, bivalves, bryozoa, fusulinids
Up to 7 meters of marine Lower Ordovician glauconitic limestones exposed occasionally in New York's Mohawk Valley. The Fonda is a member of the Tribes Hill Formation. It overlies dolomites and shales of the Wold Hollow Member and is overlain unconformally by the Chuctanunda Creek Formation.
Fossils: fairly abundant gastropods, ribeiroids, hystricurids, and Clelandia
Lower Permian shale and limestone found in Oklahoma,Kansas, and Nebraska It overlies the Janesville Shale It includes the Americus Limestone, Hughes Creek Shale, and Long Creek Limestone. It is a member of the Council Grove Group/Vanoss Group
Fossils: Marine invertebrates in some beds
A widespread unit of up to 600 meters of fossiliferous Upper Devonian marine sandstones, siltstones and shales found above the Hamilton Group in Marland, Virgina and West Virginia. It corresponds to the lower part of the Chemung Formation formation in Southern New York and Pennsylvania. It is a member of the Greenland Gap Group. The Foreknobs overlies the Hamilton age Brallier Formation and is overlain by the Hampshire Formation. It is divided into the Mallow Member, Briery Gap Sandstone, Blizzard Member, and Pound Sandstone
Fossils: Scattered Devonian marine fossils
200 meters of Upper Cambrian limestone found in Oklahoma(sw). It overlies the Honey Creek Limestone and is overlain by the Butterfly dolomite?/Signal Mountain Dolomite It is a member of the Arbuckle Group
Fossils: stromatolites, some trilobites -- not especially abundant.
A Lower Ordovician limestone exposed in the Mohawk Valley in the vicinity of Montgomery County, NY. Overlies the Chuctanunda Creek dolostone. Both are considered to be members of the Tribes Hill formation.
Fossils: TBPL
Fossiliferous Upper Ordovician shale, clay and limestone found in Southwest Ohio, and SouthEast Indiana. The Fort Ancient beds are treated as either the oldest member of the Waynesville Formation or the youngest member of the Arnheim Formation They overlie the Oregonia Member of the Arnheim Formation. They are overlain by the Clarksville member of the Waynesville Formation. They are part of the Richmond Group.
Fossils: Marine invertebrates are common, well preserved, and abundant.
Up to 30 meters of marine Lower Ordovician dolomites and dolomite breccia exposed occasionally in New York's Mohawk Valley. Overlies an unnamed dolomite and is overlain by the Palatine Bridge Formation in some areas and the Gailor Formation in others. It is the basal member of the Tribes Hill Formation.
Fossils: Unknown
Upper Devonian sandstone and shale. It overlies the Rush Formation and underlies Catskill Group rocks. It is a member of the Susquehanna Group.
Fossils: Bryozoa, Shelly fossils.
2 meters of Lower Permian limestone and flint found in Oklahoma(nc),Kansas(e), and Nebraska(se) It overlies the Barneston Formation and is overlain by the Holmesville Shale It may be equivalent to the Florence Limestone in some areas. It is a member of the Barneston Limestone/Chase Group/Oscar
Fossils: Abundant brachiopods, other marine invertebrates
Upper Devonian marine sediments of the Canadaway Group exposed on Cattaraugus Creek in Western New York. Probably a shale. Virtually no information available. It appears possibly to be overlain by glacial till and possibly to overlie the Dunkirk Black Shale
Fossils: Unknown
About 5 meters of fossiliferous Middle Devonian limestone found in Michigan(ec) It overlies the Alpena Limestone and is overlain by the Norway Point Formation. Includes the Dock Street Clay where the Dock Street Clayis present. It is a member of the Traverse Group
Fossils: Gastropods, corals, crinoid fragments
Up to 45 meters of Upper Mississippian shale with minor limestone and siltstone found in Missouri,Illinois,Indiana, and Kentucky. It overlies the Beech Creek limestone and is overlain by the Haney Limestone. It is considered to be a member of the Okaw or Golconda/Pope Groups.
Fossils: The limestones have abundant marine invertebrates. Plants in the shales.
30 meters of Upper Cambrian sandstone with thin green shales found in Iowa,Illinois,Michigan,Minnesota,Missouri,and Wisconsin. It overlies the Dresbach Shale/Jacobsville Sandstone and is overlain by St Lawrence Dolomites/Trempealeau Formation/Potosi Dolomite. It is sometimes treated as a Group and othertimes treated as a member of the Potsdam Group/Munising Group/Lake Superior Group. It includes the Miners Castle Sandstone,Chapel Rock Sandstone,Galesville Sandstone, Eau Claire Formation,Mount Simon,Ironton Sandstone,Davis Formation.
Fossils: ichnofossils,trilobites,brachiopods -- probably not abundant
The Franfort consists of often fossiliferous black Middle Ordovician shales found in the upper (Western) Mohawk River Valley of New York where overlays the Steuben formation limestones of the Trenton Group].
Fossils: TBPL
Up to 150 meters of dark, siliceous, Upper Cambrian limestone found in Maryland, Pennsylvania, and Virginia. It overlies the Antietam Formation and is overlain by the Grove Formation/Newark Group
Fossils: Present, but uncommon
An obsolete term for one to two meters of Utica Age Upper Ordovician clay found in Southwest Ohio and adjacent Kentucky. The Fulton overlies the Point Pleasant Limestone and is overlain by the Latonia Formation In modern usage, it is generally considered to be the basal member of the Economy Shale. It is a member of the Kope Formation of the Eden Group
The Fulton and Cynthiana faunas resemble those of the upper part of New York's Trenton Group and the lowermost overlying black (Utica shales and are generally considered to be of the same age.
Fossils: Triarthus, Leptobolis, Plectambonites, Merocrinus.
As much as 9 meters of Lower Permian limestone interbedded with shale found in Oklahoma(n), Nebraska(se), Kansas. It overlies the Blue Springs Shale and is overlain by the Speiser Shale. It is a member of the Garrison Formation/Council Grove Group/Oscar Group
Fossils: brachiopods,bryozoa,ostracods,bivalves
30cm of Hematitic Lower Silurian Limestone found in North Central New York where it occurs intermittently at the base of the Reynales Limestone of the Clinton Group.
Fossils: microfossils, some dwarfed macrofossils. fragments of bryozoa and crinoids
15 meters of alternating green and red-brown Permian shale found in Oklahoma(?),Kansas(e),and Nebraska(se) It overlies the Towanda Limestone and is overlain by the Stovall limestone. It is a member of the Doyle Shale of the Chase Group
Fossils: brachiopods in upper beds
Roughly 50 meters of occasionally fossiliferous Lower Ordovician dolomite exposed occasionally in outcrops West of Saratoga, New York. Overlies the Mosherville sandstone and underlies the Amsterdam or Tribes Hill formations.
Fossils: TBPL
Up to 65 meters of fossiliferous Middle and Upper Ordovician Shale, Limestone and Dolomite found in Iowa,Illinois,Minnesota and Wisconsin. It overlies the Platteville Formation and is overlain by the Maquoketa Group. It includes the Decorah shale,Dunleith Dolomite, and Wise Lake Dolomite
Fossils: Abundant, diverse marine invertebrates.
30m (max 50m) of coarse pure quartz Upper Cambrian sandstone found in Iowa,Minnesota,Wisconsin,Michigan,Illinois,Indiana. It overlies the Eau Claire Sandstone and is overlain by the Franconia Formation/Ironton Sandstone. In different areas, it is assigned to the Dresbach Group/Formation,Munising Group,Elk Mound Group or the Wonewoc Formation. It is laterally equivalent to the Davis Formation/Potosi Dolomite
Fossils: None?
48 meteres of fossiliferous Upper Cambrian clastics exposed on a few road and railroad cuts North of Saratoga Springs in New York. Modern practice would probably be to consider it to be a unit within the Theresa formation.
Fossils: TBPL
Up to 110 meters of Upper Devonian marine shales, sandstones, and siltstones of the West Falls Group found in West Central New York and South into Pennsylvania. It overlies the Grimes Sandstone/Hatch Sandstone/Rhinestreet Black Shale and is overlain by the Nunda Sandstones/West Hill Shales. .
Fossils: Uncommon A few bivalves,cephalopods,gastropods in some of the shale beds
Up to 40 meters of yellowish calcerous Upper Ordovician sandstone and shale found in Kentucky(sc). it overlies the Winchester Limestone/Clays Ferry Limestone and is overlain by the Richmond Group/Calloway Creek Formation.
Fossils: Sparse marine invertebrates. A few brachiopods
An obsolete name for 45 meters of Permian Shales with minor limestones found in Oklahoma(n),Kansas(e), and Nebraska(se). It overlies the Cottonwood Limestone and is overlain be the Wreford Limestone. The Garrison includes the Florence Shale and Neosho Formation of the Council Grove Group
Fossils: abundant, but not very diverse, marine invertebrates
Up to 80 meters of Lower Ordovician sometimes cherty dolomite found in Arkansas,Missouri,and Illinois. It overlies the Gunter Sandstone/Proctor Limestone/Eminence Dolomite and is overlain by the Roubidoux SandstoneSaint Elizabeth Formation. The Gunter Sandstone is included in the Gasconade by some authors. It is laterally equivalent to the Onenta Dolomite found in Indiana and Kentucky.
Fossils: stromatolites, gastropods, cephalopods
30 meters of Upper Mississippian limestone, oolite and sandstone found in Virginia,Kentucky,Alabama,and Georgia. It overlies the St Genevieve Limestone. It is partially laterally equivalent to the Ridenhower Shale Because of controversy over it's exact definition, some authors prefer to use the term Girkin Limestone instead.
Fossils: Marine invertebrates-crinoids,brachiopods
15 meters of abundantly fossiliferous light gray Early Silurian limestone and dolomite found near the base of the Lockport Dolomite where it overlies the Decew Limestone Shale of the Clinton Group. It is overlain by the Goat Island Dolomite. It is found in the Niagara region of New York and Ontario.
Fossils: crinoid fragments,algae,reef fossils
The Upppermost of the Middle Silurian Rochester Shale in the Rochester, New York area. 8 meters or so of of dolomitic clay. It overlies the Lewiston member of the Rochester Shaleand is overlain by the Decew Formation. It is the lateral equivalent of the Burleigh Hill member
Fossils: Lingula, few others.
Up to 550 meters of Upper Cambrian/Lower Ordovician crystalline limestone and dolomite interbedded with quartz,sandstone,and shale found in New York, Pennsylvannia, Ohio, Virginia and West Virginia. It overlies the Warrior Limestone and overlies the Larke Dolomite Divided into Stacy, Ore Hill and Mines members
Fossils: A few trilobites, conodonts
Roughly 33 meters of fossiliferous Upper Devonian black shales and occasional thin limestones found throughout the Appalachian region South of the Mohawk River and Ontario Plain in NY. In Northern New York, it includes the Geneseo Shale, North Evans Limestone,Penn Yann Shale,Ithaca Formation,Genundewa Limestone,West River Shale,Sherburne Formation and the Renwick Shale. The Genessee overlies the Tully limestone of the Middle Devonian Hamilton Group and is overlain by Upper Devonian rocks of the Sonyea Group. Different terminalogy is used in Pennsylvania, Maryland, the Virginias, Ohio, Indiana, and Michigan.
Fossils: TBPL
| Upper Devonian Sonyea Group | ||
| UPPER DEVONIAN GENESEE GROUP | ||
|---|---|---|
| WESTERN NEW YORK | CENTRAL NY-MOHAWK VALLEY | |
| West River | Ithaca | Sherburne Siltstone |
| ++[Leicester Pyrite *Leicester] | Ithaca | Sherburne Siltstone |
| ++Geneseo Shale | ||
| Penn Yann | ||
| +Genundewa Limestone | ||
| +NorthEvans Limestone | ||
| Middle Devonian Hamilton Group | ||
About 13 meters of Middle Devonian limestone or dolomite with carbonaceous interbeds found in Indiana and Illinois. It overlies Devonian breccias or the Waldron Shale/Laurel Dolomite/Louisville Limestone and is overlain by the Jeffersonville Limestone
Fossils: Present, Neither well preserved nor abundant
About a meter of Upper Devonian marine flaggy/concretionary limestones and shales containing abundant styolines found in Western and Central New York where it separates the Penn Yann grey shale from the Geneseo Shale or the West River Shales. It is member of the Upper Devonian Genesee Group.
Fossils: abundant styolines, some macrofossils
Roughly 30 meters of fossiliferous Upper Devonian marine shale found in Western New York and adjacent states near the base of the Genesee Group. The Geneseo overlies the Genundewa Limestone near the base of the Upper Devonian sequence in New York. It is overlain by the Leicester Pyrite or Penn Yann Shale.
Fossils: Abundant, diverse marine fossils - trilobites, brachiopods, ammonoids, corals, bryozoans, etc
Middle Devonian gray shale found in Michigan. It overlies the Ferron Point Formation and is overlain by the Newton Creek Limestone. It is a member of the Traverse Group
Fossils: Fish Teeth, Ostracods, brachiopods
130 meteres of Upper Odovician shale and limestone overlying the Whitby Formation or the Blue Mountain and overlain by the Queenston Shale in Ontario and Michigan near Lake Huron. - CGKN
Fossils: TBPL
Something over 20 meters of green Upper Devonian marine(?) sandstones and red shales found in Western New York and adjacent Pennsylvania. It is a member of the Conewango Group. It is overlain by the Cattaragus Formation or Wold Creek Conglomerate and overlies the Whitesville Formation
Fossils: Unknown
About 30 cm of Pennsylvanian coal found in Wyoming County West Virginia. It underlies the Gilbert Shale. It is a member of the Kanawha Group
Fossils: Plant fossils?
Up to 6 meters of fossiliferous thin bedded Upper Ordovician limestone and shale found in Kentucky(nc). Overlies the Tate Formation and is overlain by the Stingy Creek formation. Assigned as a member of the McMillan Formation/Ashlock Formation. Not to be confused with the Pennsylvanian Gilbert Shale in West Virginia
Fossils: Abundant, marine invertebrates -- brachiopods, bryozoa
Up to 40 meters of Pennsylvanian sandstone found in West Virginia. It is somewhat hazily defined and appears to consist of a 25 meter lower sandstone and a 15 meter upper sandstone separated by the Glenalum Tunnel coal? It overlies the Gilbert Shale and is overlain by the War Eagle coal. It is a member of the Kanawha series.
Fossils: None
Up to 13 meters of black Pennsylvanian marine shale found in West Virginia above the Gilbert Coal seam. It underlies the Gilbert Sandstone. It is a member of the Kanawha Group
Fossils: marine fossils
1100 meters of fossiliferous Upper Devonian marine shales,siltstones,and sandstones found in Central New York. Corresponds to the Tully formation further West. It overlies Hamilton beds and is overlain by the Sherburne formation.
Fossils: TBPL
122 meters of Upper Mississippian limestone with some chert in Tennessee(ne). It overlies the Clifton Creek Limestone and is overlain by the Fisher Creek Formation.
Fossils: Unknown, but probably present
Upper Devonian marine sediments found in Western New York and adjacent Pennsylvania. It is a member of the Conneaut Group. No other information available.
Fossils: Unknown
Upper Mississippian limestone found in central Kentucky. It overlies the St Genevieve Limestone and is overlain by the Cypress Formation. It is laterally equivalent to the Gasper Limestone/the combined Bethel and Paint Creek Limestones
Fossils: Marine Invertebrates
An obsolete name for the Early Ordovician Lebanon limestone
Up to three meters of shaly Pennsylvanian coal, but usually 60cm or less, found in West Virginia in the area where West Virginia, Kentucky, and Virginia meet. It overlies and is overlain by the Gilbert Sandstone It is the lowest potentially commercial coal bed in the Kanewha series.
An Upper Devonian marine formation found in South Central New York -- presumably shales,siltstones, and/or sandstones. It is a member of the Sonyea Group and apparently occupies the entire interval between the older Genesee Group and the younger West Falls Group in the region where it is found.
Fossils: ichnofossils, (fairly abundant?) mollusks, brachiopods
Up to 60 meters (but usually much less) of crinoidal Upper Mississippian limestones, shales and minor sandstones. Found in Illinois, Indiana, Missouri, Kentucky and Tennessee. It overlies the Hardinsburg Formation and is overlain by the Leitchfield Formation/Tar Springs Formation/Mansfield Formation. Assigned to the Okaw/Stephensport/Pope Groups
Fossils: Abundant marine invertebrates - brachiopods, blastoids, bryozoa
A fossiliferous Lower Devonian Limestone that occupies the lower portion or entirety of the Oriskany Sandstone interval in the Catskill area of New York and adjacent New Jersey. It overlies Helderberg limestones and underlies Oriskany sandstones or Esopus grits.
Fossils: TBPL
Highly fossiliferous Middle Ordovician fine textured grainstone limestones interbedded with thin fossiliferous shale layers. It may be the only member of the Trenton Group in some areas SouthEast of the Adirondacks. It is equivalent to the Sugar River and Shoreham formations in the Champlain Valley and may possibly be used for the Sugar River interval in Southwestern Quebec.
Fossils: Abundant, diverse Middle Ordovician marine fossils -- Brachiopods, Bryozoa, Occasional trilobites
A few meters of fossiliferous Middle Silurian marine dolomitic limestone occupying the interval between the Rochester Shale and the DeCew Formation or higher portions of the Lockport Group in Western New York and other parts of the Norther Applachians.
Fossils: corals, brachiopods-Nucleospira
Half a meter of Lower Permian limestone found in Kansas(ne) and Nebraska(se) It overlies the Johnson Shale and is overlain by the Bennett Shale. It is a member of the Red Eagle Limestone/Elmdale Shale/Wabaunsee Group.
Fossils: fusulinids, bryozoans, brachiopods
Up to 320 meters of Middle Ordovician sandstone, shale, and carbonates found in the Iowa?, Minnesota, Wisconsin?, Illinois?. It overlies the St Peter Sandstone and is overlain by Black River Limestones/Platteville Limestone.
Fossils: sparse marine invertebrates? mostly microfossils?
Up to 65 meters of Upper Mississippian limestone and shale found in Illinois,Indiana,Kentucky,Tennessee,Missouri,and Georgia It overlies the Cypress Formation and is overlain by the Hardinsburg Formation Subdivided into the Beech Creek Limestone, Big Clifty Sandstone, Fraileys Shale, and Haney Limestone It is considered to be a member of the Stephensport/Pope Groups
Fossils: Diverse and often abundant marine invertebrates.
An Upper Devonian marine shale found in Western New York above the Dunkirk black Shale of the Canadaway Group/Perrysburg Group. It is overlain by the Laona Sandstone.
Fossils: Unknown
13 meters of thick bedded brown-gray Middle Silurian dolomites of the Lockport Group found in New York and Ontario in the vicinity of Niagara Falls. It overlies the Gasport Limestone and is overlain by the similar Eramosa Dolomite from which it is differentated by the absence of bituminous layers in the Goat Island. The name Goat Island was proposed in 1947 to replace a preoccupied name -- the Suspension Bridge Dolomite. Three members -- the Niagara Falls, Ancaster, and Vinemount Members -- have been proposed. It is thought to be in part equivalent to the Penfield Dolomite further East.
Fossils: Probably, but fossils in dolomite are often poorly preserved. Conodonts
An Ordovician shale found above the Collingswood Shale in the Great Lakes Region. There is no GEOLOX entry and only a single undetailed card in the Canadian CGKN.
2 meters or more of Black River age Middle Ordovician limestone found in Illinois,Iowa,Missouri and Wisconsin It overlies the Mifflin Limestone/McGregor Limestone and is overlain by the Decorah Shale. A member of the Platteville Group/Plattin Group
Fossils: abundant fossils- trilobites,brachiopods, etc
About 30 meters of Lower Mississippian chert and limestone found in Arkansas(nw), Kansas(se), Missouri(sw), and Oklahoma(ne). It overlies the Reeds Spring Formation and is overlain by the Joplin Formation/Keokuk Limestone. A member of the Boone Formation
Fossils: corals, bryozoans, brachiopods, rarely mollusks and trilobites.
Isolated outcrops of Middle Pennsylvanian sandstones and shales found in South Central Lower Michigan. Thickness unknown. They overlie the Saginaw Group and are overlain by glacial debris. It is considered to be a Group and includes the Woodville, Eaton and Ionia Sandstones.
Fossils: Plants, invertebrates, ichnofossils.
5 meters of blue Permian shale with thin limestone interbeds found in Kansas(e), and Nebraska(se). It overlies the Stovall Limestone and is overlain by the Cresswell Limestone It is a member of the Winfield Shale of the Chase Group.
Fossils: Marine invertebrates in the limestone - brachiopods, bryozoa
About 35 meters of fossiliferous of Upper Ordovician Limestone interbedded with calcaerous shales found in SouthWest Ohio and adjacent Kentucky. It overlies the Fairview Formation/Miamitown Shale It is overlain by the Bull Fork Formation/Arnheim. It includes the Bellevue,Corryville, Mt Auburn and Straight Creek formations. It is laterally equivalent to the Calloway Creek Limestone and Ashlock Formation. The Grant Lake Limestone is a component of the Cincinnati Group.
Fossils: Diverse, abundant, well preserved Ordovician Marine fossils.
Up to 40 meters of Middle Ordovician marine limestone found in Virginia and Tennessee. It overlies the Benbolt Formation/Cliffield Formation/Beekmantown. It is overlain by the Wardell Formation.
Fossils: Almost certainly present, appears to be a Chazy age fauna.
Middle Devonian limestone and shale found in Northern Lower Michigan. It overlies the Koehler Formation and is overlain by the Charlevoix Limestone. It is a member of the Traverse Group
Fossils: Abundant Devonian marine fossils. corals-Hexagonia
Up to 600 meters of fossiliferous marine Upper Mississippian limestones found in Kentucky, Maryland, Pennsylvannia,Virginia, and West Virginia. It overlies the Maccrady Shale/Price Formation It is overlain be the Upper Newman Limestone/Bluefield Formation/Mauch Chunk Group
Fossils: often abundant marine invertebrates
About 5 meters of fossiliferous Middle Ordovician limestone and shale found the middle of a Limestone sequence in central Kentucky. It overlies the Lexington Limestone and is overlain by the Point Pleasant Limestone A part of the Lexington Limestone
Fossils: Marine invertebrates
An obsolete term for the Upper Cambrian Hoyt Limestone found in the Saratoga, NY area.
Fossils: TBPL
700-1200 meters of marine Upper Devonian redbed shale, sandstone and siltstone found in Ohio and West Virginia where it occupies the Chemung interval. It overlies the Brallier Formation and is overlain by the Hampshire Formation. It includes the Scherr Formation and the Foreknobs Formation.
Fossils: marine invertebrates, plants
15 meters of Lower Permian limestone and calcaerous shale found in Oklahoma(n), Kansas(e), Nebraska(se) It has been subdivided into the Sallyards limestone, Legion shale, Burr limestone, Salem Point shale, and Neva limestone. It is underlain by Roca shale and overlain by the Eskridge shale It is a member of the Council Grove Group
Fossils: bivalves, brachiopods, gastropods, bryozoans, forams, crinoids, echinoids
Thick proterozoic metasediments exposed throughout the Adirondack Mountains and adjacent Canada as well as the Southern Green Mountains of Vermont. Grenville rocks are estimated to be from 1300 to 950 millon years old. The only known fossils in the Grenville Complex per se are stromatolites, but fossil bacteria have been identified from similar rocks in Western Ontario. The Grenville rocks are overlain by Middle Cambrian Potsdam Sandstones on the Laurentian platform. In the Green Mountains they are overlain by a sequence of Ediacarian and/or Lower Cambrian sediments.
Fossils: TBPL
Up to 55 meters of thin bedded yellowish Middle Ordovician limestone found in Ohio and Kentucky. It overlies the Logana Formation and is overlain by the Brannon Limestone/Tanglewood Limestone. It is laterally equivalent to the Jessamine Limestone and Benson Limestone
Fossils: brachiopods, bryozoans, gastropods, ostracodes, crinoids, pelecypods, trilobites
About 8 meters of Upper Devonian marine shales, sandstones, and siltstones of the West Falls Group found in West Central New York and South into Pennsylvania. It overlies the Hatch Sandstone and is overlain by the Gardeau Shale.
Fossils: Present. Primarily brachiopods
Almost 20 meters of red Early Silurian Medina Group sandstone,mudstone and shales that overlies the Devils Hole Sandstone and is overlain by the Thorold Sandstone. It is found in the Niagara region of New York and Ontario. It includes beds sometimes referred to as the Devils Hole Sandstone, about one meter of phosphatic sandstone often referred to as the Artpark Phosphate Bed, Power Glen Formation and a heterogenious collection of beds called the Cabot Head Formation
Fossils: abundant ichnofossils, marine invertebrates
Trenton Age Middle Ordovician Limestone found in the Upper Peninsula of Michigan. It overlies the Chandler Falls Formation and is overlain by the Collingswood Shale.
Fossils: Gastropods,brachiopods,trilobites,bivalves,crinoids,bryozoa
Up to 450 meters of Upper Cambrian/Lower Ordovician limestone and dolomite found in Maryland. It overlies the Frederick Formation
Fossils: a few trilobites, brachiopods, cephalopods, conodonts
Up to 30 meters of Middle Silurian Limestone/Dolomite found in Michigan, Ontario, Ohio, New York, and Pennsylvania. It overlies the Eramosa Dolomite and is overlain by the Vernon Shale. It is a member of the Niagara Group/Lockport Group.
Fossils: Moderately abundant? Stromatolites, Conodonts, probably others
Up to 90 meters of fossiliferous Middle Ordovician Black River age limestone found in Ontario, Northern New York, and Northwest Pennsylvania. It overlies the Shadow Lake formation and is overlain by the Bobcaygeon formation.
Fossils: TBPL
Up to six meterns of Lower Ordovician sandstone or sandy dolomite found in Illinois, Missouri, Arkansas, and Oklahoma. It overlies the Proctor Limestone and is overlain by the Gasconade Dolomite. Some authors treat it as a member of the Gasconade Dolomite.
Fossils: Few or none.
About 5 meters of fossiliferous brown Middle Ordovician Limestone/dolomite or shale found in Iowa, Illinois, Minnesota, Missouri, and Wisconsin. In many areas it is regarded as the middle member of the Decorah Group. It overlies the Sprechts Ferry Formation and is overlain by the Ion Formation. It is a member of the Decorah/Galena Groups
Fossils: abundant brachiopods, bryozoans, mollusks, and sometimes a few trilobites.
An obsolete name for roughly 30 meters of unfossiliferous gray, olive, reddish Upper Silurian quartzite found in Orange County, New York. It overlay the Shawangunk Conglomerate and was overlain by the Bloomsburg Sandstone. Beds originally assigned to the Guymard were reassigned to the underlying and overlying formations in 1993.
Fossils: Few or none.
Up to 830 meters of fossiliferous Middle Devonian shales found throughout the Appalachian region South of the Mohawk River and Ontario Plain in NY. It countains a few thin limestone units. In Northern New York, it includes the Marcellus,Skaneateles,Ludlowville and Moscow shales. In SouthEastern New York, the Hamilton interval above the Marcellus is called the Mount Marion formation. The Hamilton overlies limestones of the Onondaga Group and is overlain by Upper Devonian rocks of the Genesee Group. Different terminalogy is used in Pennsylvania, Maryland, the Virginias, Ohio, Indiana, and Michigan.
Fossils: Diverse and often abundant marine invertebrates in some beds
| Upper Devonian Genesee Group | ||
| MIDDLE DEVONIAN HAMILTON GROUP | ||
|---|---|---|
| WESTERN NEW YORK | CENTRAL NY-MOHAWK VALLEY | |
| ++Tully Pyrite | ++Tully Limestone | |
| ++Moscow Shale | ||
| Tichenor Limestone | ||
| Ludlowville Shale | ||
| Centerfield Limestone | ||
| Skaneateles Shale | ||
| Stafford Limestone | ||
| Marcellus Shale | Oatka Creek Shale | |
| Marcellus Shale | Cherry Valley Limestone | |
| Marcellus Shale | Mount Marion Shale | |
| Middle Devonian Onondaga Group Limestones | ||
Up to 100 meters Upper Mississipian/Lower Pennsylvanian sometimes calcaerous shale and sandstone found in Arkansas,Missouri,and Oklahoma. It overlies the Pitkin Limestone and is overlain by the Bloyd Shale. It is sometimes divided in Cane Hill and Prarie Grove members
Fossils: sometimes abundant-bivalves, gastropods, cephalopods, brachiopods, crinoids, trilobites, palynomorphs, plants
15 meters of Lower Permian shale, limestone and sandstone found in Oklahoma, Kansas(e), and Nebraska(se). It overlies the Five Point limestone and is overlain by the Foraker limestone It is a member of the Janesville Shale of the Admire Group
Fossils: Bivalves, bryozoa, and brachiopods
As much as 1000 meters of gray and red non-marine Upper Devonian shales and mudstones found in Pennsylvania Maryland, Virginia, and West Virginia. It overlies Chemung stage Upper Devonian marine beds such as the Jennings Formation/Foreknobs Formation/Greenland Gap Group and is overlain by the Mississippian Pocono Group. It corresponds roughly to the Catskill Group of older geologists.
Fossils: A few plants
200 meters of Lower Cambrian sandy shale found in Tennessee, North Carolina, and Virginia. It overlies the Unicoi Sandstown and is overlain by the Erwin Sandstone It is a member of the Chilhowee Group
Fossils: A few ichnofossils
Up to 22 meters of Upper Mississippian limestone and shale found in Illinois,Indiana,Kentucky,and Missouri. Overlies Fraileys shale/Big Clifty sandstone and underlies the Hardinsburg sandstone. Assigned to the Stephensport/Okaw/Golconda/Pope Groups
Fossils: Abundant marine invertebrates in the limestones
28 meters or less of sparsely fossiliferous green-gray Upper Devonian marine shale found in Western New York and SouthWest into other states. It also contains thin black shale beds as well as small calcereous, phosphatic and pyritic nodules. In New York, it is the uppermost member of the West Falls Group. It overlies the black marine shale of the Pipe Creek Shale and is overlain by the black marine shale of the Dunkirk Formation of the Canadaway Group. To the East, it grades into the silter Wiscoy Formation
Fossils: Sparse, but fairly diverse. Corals, cephalopods, brachiopods, wood fragments.
Up to 30 meters of thinbedded Upper Mississippian sandstone found in Missouri,Illinois,Indiana,Kentucky, and Tennessee. It overlies the Golconda Limestone/Haney Formation and is overlain by the Glen Dean Limestone/Sloans Valley/Mansfield Formation. The Hardinsburg is considered to be a member of the Stephensport,Okaw,Pope Group.
Fossils: None
Up to 50 meters of thin bedded, cherty Middle Ordovician Limestones found in Virginia and Tennessee. It overlies the Ben Hur Limestone and is overlain by the Eggleston Limestonee. It is a member of the Moccasin Limestone
Fossils: Sparse except in the very topmost beds - bryozoa,brachiopods,cephalopods
Possibly as much as 400 meters of gray Lower Cambrian shale/slate/phyllite found in Maryland(w),Pennsylvania(sc),Virginia(w) and West Virginia(e). It overlies the Weverton Formation underlies the Antietam sandstone
Fossils: Some ichnofossils
Up to 100 meters of Upper Devonian marine shale with some calcaerous beds and limestone found in Central Pennsylvania as well as Maryland and West Virginia. Where exposed, it is the oldest Upper Devonian formation. It overlies the Tully Limestonee/Millboro Shale/Mahantango Shale. It is a member of the Susquehanna Group
Fossils: Conodonts, Goniatites
Up to 650 meters of Upper Mississippian sandstone with minor siltstone and shale found in Alabama, Mississippi, Georgia, Kentucky, and Tennessee. It overlies the Pride Mountain Formation/Monteagle Formation and is overlain by the Bangor Formation/Floyd Shale/Cretaceous beds. Laterally equivalent to the Floyd Shale/Newman Formation
Fossils: Marine fossils, plants, ichnofossils
Up to 65 meters of Middle Pennsylvanian sandstone and shale found in Oklahoma, Arkansas, and Missouri. It overlies the Atoka Formation/Warner Formation and is overlain by the MacAlester Shale/Hartshorne Coal/Riverton Formation. member of the Krebs Group
Fossils: A few plant fragments
Pennsylvanian Coal found in Arkansas and Oklahoma. It consists of two beds separated by about 15 meters of sandstone -- up to 2.5 meters of coal in the lower bed and an additional meter in the upper bed. One of the beds -- sources differ on which -- lies between the Hartshorne Sandstone and the MacAlester Shale.
Fossils: plants?
Up to 6 meters of Upper Pennsylvanian shale found in Iowa,Nebraska,Kansas(e),Missouri,and Oklahoma. It overlies the Reading Shale and is overlain by the Elmont limestone. It is a member of the Emporia Limestone/Wabaunsee Group
Fossils: None?
Up to 330 meters of Upper Devonian marine shales, sandstones, and siltstones of the West Falls Group found in West Central New York and South into Pennsylvania. It overlies the Rhinestreet Black Shale and is overlain by the Gardeau Shale/Grimes Sandstone.
Fossils: Uncommon. Those present resemble those of the Cashaqua Formation.
More than 33 meters of unfossiliferous deformed breccia containing cherts,limestone,dolomite,shale and sandstones. It is Middle to Late Ordovician age. It is found the the northern Champlain Valley of Vermont where it overlies the Iberville Formation and is overlain by Pleistocene beds
Fossils: None?
up to 6 meters of Lower Permian shale with occasional limestone and sandstone found in Kansas(e) and Nebraska(se). It overlies the Aspinwall limestone and is overlain by the Falls City limestone It is a member of the Onaga Shale/Admire Group/Chicago Mound member of the Aspinwall Limestone
Fossils: A few marine invertebrates in some places - crinoid fragments,bryozoa,bivalves
Upper Devonian marine shales and sandstones found in West Central New York. It is a member of the Chadakoin Formation of the Conneaut Group. It overlies the Germania Formation and is overlain by the Wellsville Formation
Fossils: Unknown
Latest Silurian and Earliest Devonian sediments found in the NorthEastern United States. The Helderberg is absent in Western New York, but is present in Eastern regions of New York along the West side of the Hudson River and also in the Green Mountain Pond outlier parallel to and East of the Applachians in the Southernmost part of the state. It is generally regarded as having four members -- the Coeymans, New Scotland, Kalkberg and Becraft formations. The Helderberg overlies the Silurian Cobleskill dolomite and underlies the Devonian Oriskany formation.
Fossils: TBPL
| Lower Devonian Oriskany Group Sandstones | |
| LOWER DEVONIAN HELDERBERG GROUP | |
| EASTERN NEW YORK (CATSKILL REGION) | |
| Alsen-+Port Ewen | |
| ++Becraft Limestone | |
| ++Kalkberg Limestone | |
| ++New Scotland Limestone | |
| ++Coeymans Limestone | |
| Upper Silurian ++Cobleskill Dolomite | |
about 30 meters of Lower Cambrian shale,clay, and coarse sandstone found in Tennessee and North Carolina. it overlies the Hesse Sandstone and is overlain by the Shady Dolomite. It is a member of the Chilhowee Group/Erwin Formation/Hesse Sandstone
Fossils: ichnofossils, sparse(?) trilobites at one locality
The name Herkimer may have been used at one time for some Cambrian age sandstone in New York's Mohawk Valley, but now days if used at all it applies to a Middle-Upper Silurian Sandstone found at the top of the Clinton Group in East Central New York. The Easternmost outcrops are sandstone called the Jordanville member. West of Ilion Gorge, it becomes a heterogenous assemblege of Sandstone, shale,dolostone, and hematite identified as the Joslin Hill member.
Fossils: TBPL
Up to 60 meters of fossiliferous Middle Ordovician Limestone and Shale found in Alabama,Gerorgia,Tennessee and Kentucky. It overlies the Carters Creek Limestone And is overlain by the Bigby Limestone/Cannon Limestone
Fossils: marine invertebrates
Five meters of soft, fossiliferous Upper Permian/Lower Pennsylvanian limestone found in Oklahoma(n), Kansas(e), and Nebraska(se). It overlies the Enterprise Shale and is overlain by the Pearl Shale It is a member of the Marion Formation/Chase Group/Oscar Group
Fossils: Abundant marine invertebrates
160 meters of white Early Cambrian sandstone or quartzite found in Tennessee, North Carolina and Virginia. The name may have been abandoned in favor of the Erwin Quartzite It overlies Overlies Murray Shale and underlies Apison Shale/Shady Dolomite/Helenmode Formation It is a member of the Chilhowee Group/Erwin Sandstone
Fossils: None (Lower Cambrian marine invertebrates have been found in the overlying and underlying beds).
Four meters of fossiliferous Lower Silurian marine limestone with a basal phosphate bed found in Western New York and adjacent Ontario. The Hickory Corners is a westward extension of the Reynales Formation further East. It overlies various members of the Clinton Group or Medina Group and is overlain by the Rockway Dolomite of the Irondequoit Limestone.
Fossils: brachiopods, crinoid columnals, bryozoa
Up to 140 meters of Middle Ordovician limestones with minor calcaerous shales found in Kentucky(nc). No older formations are exposed in its area of exposure. It is overlain by the Lexington Limestone It includes the Camp Nelson, Oregon, and Tyrone Limestones. It is laterally equivalent to the Stones River Group
Fossils: Ichnofossils, some marine invertebrates
15 to 33 meters of interbedded marine(?) Upper Silurian largely red shale and dolomite found near the junction of New York, New Jersey, and Pennsylvania. The Decker/Decker Ferry overlies the Shawangunk Conglomerate and is overlain by the Binnewater Sandstone
Fossils: Uncommon. Linguloid brachiopods have been found.
1300m of Middle to Upper Ordovician marine Martinsburg Shale and graywacke sandstone found in New Jersey. It overlies the Ramseyburg Formation and is overlain by the Shawangunk Conglomerate.
Fossils: Sparse. Graptolites.
Apparently a Trenton Age age limestone associated in some way with the Steuben Limestone at the top of the Trenton Group in New York.
15 meters of fossiliferous, dark gray Upper Mississippian limestone and sandstone found in Arkansas(n), Missouri(s), Oklahoma(e). It overlies the Boone Formation/Ordnance Plant Formation/Moorefield Formation/Quapaw Limestone. It is overlain by the Fayetteville Formation/Batesville Formation. It is a member of the Batesville Sandstone/Mayes Group
Fossils: Abundant marine invertebrates - mollusks, brachiopods, bryozoans, corals, echinoderms, trilobites
An obscure Upper Devonian marine sandstone formation found in Western New York where it overlies the Rawson Formation/Wellsville Formation and underlies the Whitesville Formation. It is a member of the Conneaut Group. The Hinsdale appears to represent an isolated sand ridge similar to the Machias and Cuba Formations
Fossils: Ichnofossils,shell fragments,shells(?)
350 meters of Upper Mississippian sandstone and shale found in Tennessee, Kentucky, West Virginia and Virginia. It overlies the Bluefield Formation and is overlain by the Princeton Sandstone/Conglomerate. It is a member of the Mauch Chunk Group/Pennington Group
Fossils: None?
A formation proposed on lithogic grounds consisting of the uppermost portion of the Middle Ordovician RockCliffe Formation formation found in Eastern Ontario and the lower parts of the overlying Shadow Lake Formation.
Fossils: TBPL
10 meters of calcaerous Permian Shale with a 30cm limestone bed near the middle found in Oklahoma, Kansas(e), Nebraska(se). It overlies the Fort Riley Limestone and is overlain by the Towanda Limestone It is a member of the Doyle Shale/Oscar Group/Chase Group
Fossils: Marine invertebrates.
Up to 200 meters of metamorphised Middle Ordovician Limestone ("Tennessee Marble") found in Virginia, Tennessee and Georgia. It overlies the Lenoir limestone and is overlain by the Ottosee Shale/Tellico Sandstone
Fossils: bryozoa,crinoids
300 meters of Middle and Upper Cambrian limestone and dolomite found in Georgia, Alabama, Tennessee, Virginia and West Virginia. It overlies the Russell formation and underlies the Nolichucky Shale/Copper Ridge Dolomite. The Honaker is laterally equivalent to the Rutledge Limestone-Rogersville Shale-Maryville limestone sequence to its West. It is a member of the Conasauga Group.
Fossils: None?
460-640 meters of Upper Devonian sandstone and shale found in NorthEastern Pennsylvania and adjacent New York. It is considered to be a member of the West Falls Group/Catskill Group. In Pennsylvania, the Honesdale overlies the Damascus formation and is overlain by the Cherry Ridge Formation. In New York, it is overlain by the Slide Mountain Formation
Fossils: Unknown. If present, probably shallow water marine?
Up to 80 meters thin bedded Upper Cambrian shaly limestones found in Oklahoma(wc). It overlies the Reagan Sandstone and is overlain by the Fort Sill formation/Royer formation. It is a member of the Timbered Hills Group
Fossils: Some trilobites in the limestones
3.5 meters of varicolored Lower Permian shale with minor limestone found in Nebraska(se) and Kansas(e). It overlies the Eiss Limestone and is overlain by the Middleberg Limestone. It is a member of the Bader Limestone/Garrison Formation/Council Grove Group
Fossils: bryozoans, brachiopods, pelecypods, and gastropods
Up to 100 meters of Pleistocene sand and silt found in Wisconsin(sc) It is underlain by Paleozoic bedrock and is either the surface formation or overlain by the Kewaunee Formation. It is laterally equivalent to the Copper Falls Formation
Fossils: Plant material, wood
2 meters of Lower Permian limestone with shale partings found in Kansas(ne) and Nebraska(se). It overlies the Stine shale and is overlain by the Hughes Creek Shale/Oaks Shale. It is a member of the Hamlin Formation/Janesville Shale/Admire Group
Fossils: brachiopods, bryozoa, Bivalves
Up to 27 meters of fossiliferous Upper Cambrian limestone interbedded with dolomite. It exposes well preserved stromatolitic reefs in a small area West of Saratoga Springs, New York. Although it was originally considered to be the basal member of the Little Falls Dolomite, modern practice might be to consider it to be a unit within the Theresa formation. Also called the Greenfield Limestone by some early workers
Fossils: TBPL
A nineteenth century term for dark, sparsely or non-fossiliferous Upper Ordovician shales found in the NorthEast and as far West as Iowa that occur between the Middle Ordovician Limestones and Silurian rocks of various kinds. Generally, the lowest of these shales are organic rich with marine fossils, and were termed "Utica Shales". Unlike many older terms, the Hudson River Group which seems never to have been terribly precise seems to have fallen completely out of modern usage.
15 meters of blue marine Lower Permian shale and limestone found in Kansas(ne) and Nebraska(sw). It overlies the Houchen Creek limestone and is overlain by the Long Creek limestone. It is a member of the Elmdale Shale Same as the Hughes Creek Shale below
Fossils: brachiopods, bryozoa
15 meters of Lower Permian shale and thin limestones found in Kansas(ne) and Nebraska(se). It overlies the Houchen Creek limestone and is overlain by the Long Creek Limestone. It is a member of the Elmdale Shale of the Wabaunsee Formation. Same as the Hughes Brook Shale above
Fossils: bryozoa, brachiopods
Highly fossiliferous Middle Ordovician grainstone limestones interbedded with very thin fossiliferous shale layers. It is found in Southwestern Quebec and SouthEastern Ontario. It overlies the Napanee Limestone of the Trenton Group and is overlain by the Sugar River Formation of the Trenton Group. It is equivalent to the Kings Falls Formation in New York.
Fossils: TBPL
Sparsely fossiliferous Lower Ordovician silty dolomites and clastic rocks presumably equivalent to the uppermost Ogdensburg formation in the US. The Huntingdon is exposed in South West Quebec. It overlies the Ogdensburg member of the Beauharnois formation and may be treated as the uppermost member of the Beauharnois. It is overlain by the Middle Ordovician Carillon formation.
Fossils: TBPL
100 meters or more of black Upper Devonian shale found in Ohio and adjacent states where it occupies the same interval as the Dunkirk black shale in New York and the New Albany black shale In the Illinois Basin. The name is used by some authors for beds in all the states of the Applachian Basin except New York. In Ohio, the Huron overlies the Olentangy Shale and is overlain by gray Chagrin Shales. It is considered to be part of the Ohio Shale.
Fossils: sparse vertebrates, invertebrates, plants
Up to 120 meters of Middle Ordovician limestone found in Virginia and Tennessee. It overlies the Martin Creek limestone and underlies the Woodway limestone. It is a member of the Chickamauga Group
Fossils: fossil fragments
300 to 600 meters of Middle to Late Ordovician non-calceourous black shale interbedded with thin dolomites. It is found the the northern Champlain and Richilieu Valley of Vermont,New York and Quebec where it overlies the similar, but more calcerous Stony Point formation and is overlain by the Hathaway Formation or Pleistocene beds. It is unfossiliferous except for very occasional graptolites.
Fossils: Rarely graptolites?
20 meters of sparsely fossiliferous black Middle Silurian calcaerous shale and dolomites found in Eastern New York where it occupies the Lockport interval between the Herkimer Sandstone and the Vernon Formation. It is assigned to either the Lockport or Salina Group. Beds at the top of the formation have Eurypterids.
Fossils: stromatoporoids, eurypterids
Roughly 35 meters of Black Middle Ordovician Utica Shale found in the Mohawk Valley of New York where the Utica Shales is divided into two formations by the intervening Dolgeville Limestone. The Indian Castle member of the Utica Shale overlies the Dolgeville Limestones and is overlain by similar black shale of the Frankfort formation.
Fossils: TBPL
Upper Ordovician shale and sandstone found in the Lower Mohawk Valley of New York overlying the Schenectady Formation and overlain by the Rondout formation.
Fossils: TBPL
Name assigned to a shale found at the top of the Big Clifty Sandstone at some localities. Not to be confused with the Indian Springs member of the Bird Spring Formation in Nevada
Up to 23 meters of varicolored Upper Ordovician shale with minor limestone found in Alabama,Georgia, and Tennessee. It overlies the Catheys formation and underlies Leipers formation. It is a member of the Chickamauga Group
Fossils: bryozoa, brachiopods, carbonized bivalves (???)
3 meters(?) of Middle Ordovician dolomite and shale found in Iowa, Illinois, Minnesota and Wisconsin. It overlies the Guttenberg Formation and is overlain by the Galena Limestone/Kimmswick Limestone It is a member of the Decorah Formation/Dunleith Formation.
Fossils: Marine invertebrates - Brachiopods, trilobites, ostracods, etc
An unknown thickness of coarse, varicolored Middle Pennsylvanian sandstones found in Michigan(sw). They overlie the Saginaw Group and may be overlain by or include possibly Jurassic Red Beds. It is a member of the Grand River Group.
Fossils: Plants, pollen
vari-colored non-marine Upper Devonian siltstone,sandstone and conglomerate found in Pennsylvania. It overlies the Trimmers Rock Formation and is overlain by the Sherman Creek Formation. It is a member of the Catskill Formation
Fossils: plant fragments, root traces
Up to 22 meters of fossiliferous Lower to Middle Silurian Clinton Group Limestone, Shale and Sandstone found along a line between Rochester and the Bruce Peninsula in Canada. It is overlain by the Rochester Shale. It includes a number of fairly thin formations: Irondequoit Limestone,Rockway Dolostone (considered a separate formation by some authors), Hickory Corners Limestone, Neahga Shale, and Kodak Sandstone.
Fossils: TBPL
Up to 5 meters of hard Upper Cambrian sandstone found in Iowa, Indiana, Illinois,Minnesota,Wisconsin and Michigan. It overlies the Dresbach Sandstone/Galesville Sandstone and is composed primarily of detrial material from the underlying bed. It is overlain by the remainder of the Franconia Formation. The Ironton is an alternate name for the Davis Formation. It is a member of the Franconia Sandstone/Wonewoc Formation/Munising Group
Fossils: A few marine invertebrates
Three to four meters of dark Middle Ordovician limestone found above the Lowville Limestone and below Trenton age rocks in areas around the Adirondacks in NY, Northwest Vermont, Southwest Quebec, and SouthEast Ontario. It is considered to be part of the Black River Group.
Fossils: TBPL
A possibly obsolete term for 100 meters(?) of Upper Cambrian and Lower Ordovician limestones and dolomitews of the Watts Bight and Boat Harbour Formations found in Newfoundland. It overlies the Port au Port Group and is overlain by the Catoche Formation It is a member of the Saint George Group
Fossils: stromatolites, conodonts and poorly preserved gastropods and cephalopods
An Upper Devonian marine shale containing found in Central New York where it occupies the interval above the Geneseo Shale occupied further West by the West River Shales. It is member of the Upper Devonian Genesee Group.
Fossils:
Apparently a local name for a Middle Ordovician limestone found above the St Peter Sandstone in Izard and Sharp Counties Arkansas
Fossils: Unknown
Up to 300 meters of early Middle Ordovician Limestone and calcaerous shale found in Eastern Pennsylvania and adjacent New Jersey. It overlies the Kittatinny Limestone and is overlain by the Martinsburg Shale.
Fossils:
Up to 500 meters of red and brown Precambrian sandstone and clay found in Michigan and Wisconsin. Its relationship to other formations is uncertain. It is a member of the Keweenawan Supergroup.
Fossils:
25 meters of Lower Permian shale, sandstone, limestone and coal found in Kansas(ec) and Nebraska It is divided into the Hamlin Shale, Five Point Limestone, and West Branch Shale. It overlies the Falls City limestone and is overlain by the Foraker limestone. It is a member of the Admire Group
Fossils: Abundant Fusulinids, brachiopods, and bryozoans in the limestones
As much as 60 meters of fossiliferous marine Upper Devonian shales and sandstones in Western New York and much of the Northern Appalachians. It overlies the West Falls Group and overlain by the Canadaway Group. Typically consists of a basal black shale (Pipe Creek Shale) overlain by gray shale (Hanover Shale) and sometimes a sandstone (Wiscoy Sandstone).
Fossils: TBPL
Up to 200 meters of fine grained Lowest Ordovician cherty dolomite found in Arkansas,Missouri,and Oklahoma. It overlies the Roubidoux Formation and is overlain by the Cotter Dolomite. It is laterally equivalent to part of the Shakopee Dolomite in Illinois and Kentucky.
Fossils: very rare
Up to 20 meters of gray fossiliferous Lower and Middle Devonian limestone found in Indiana and Kentucky. It overlies the Louisville Limestone and is overlain by the Sellersburg Limestone. It is a member of the Muscatatuck Group.
Fossils: Abundant Corals, others
1000 meters of Upper Devonian marine shales and sandstones found in Virginia, West Virginia, Maryland, and Pennsylvania. It overlies the Romney Shale and is overlain by the Hampshire Formation.
Fossils: some marine invertebrates
An early name for portions of the Middle Ordovician Lexington Limestone found in Kentucky. It is overlain by the Benson Limestone and is laterally equivalent to the lower portion of the Grier Limestone.
Fossils: Probably marine invertebrates
104 meters of Middle Ordovician limestone and siltstone found in Tennessee. It overlies the Mascot Dolomite and is overlain by the Carters Limestone. It is laterally equivalent to the Pond Spring Formation, Murfreesboro, Ridley, and Lebanon Limestones It is a member of the Stones River Group
Fossils: Unknown
Up to 190 meters of brecciated dolomitic Middle Ordovician sandy shallow water dolomite found in Arkansas,Missouri,illinois,Indiana and Kentucky. It overlies the Jefferson City Dolomite/Dutchtown Dolomite/Crystal City Sandstone and is overlain by Trenton Age Limestones/Plattin Limestone. It is divided into six members - Abernathy, Augusta, Boles, Defiance, Matson #Matson}, and [Metz.
Fossils: A few bivalves in the bottom portion.
Upper Devonian laminated gray marine mudstones found in South Central New York -- presumably shales,siltstones, and/or sandstones. It is a member of the Sonyea Group and is apparently an Eastern equivalent of the Middlesex Shale. It's relationship to the Glen Aubrey Formation is unclear. It is apparently separated from the older Genesee Group below and the younger Cashaqua Formation above by thin black shale formations -- the Mountour below and the Sawmill Creek above.
Fossils: sparse marine invertebrates
6 meters of Lower Permian shale found in Kansas(ne) and Nebraska(se). It overlies the Long Creek limestone and is overlain by the Glenrock limestone. It is a member of the Elmdale Shale of the Wabaunsee Group.
Fossils: A very few marine invertebrates
Lower Silurian dolomite in the Medina Group found in Western New York and adjacent Ontario where it overlies the Whirlpool Sandstone and is overlain by the Balls Falls Formation. The Jolley Cut corresponds largely to the Manitoulin Dolomite of pre-1990 authors
Fossils: Dolomitized bioherms containing brachiopods, acritarchs, bryozoa
170m of Middle to Upper Ordovician marine Martinsburg varicolored Shales and basalts found in Lebanon County Pennsylvania. It is overlain by the Shochary Sandstone.
Fossils: None?
An obsolete term for up to 33 meters of Lower Mississippian Keokuk crinoidal limestone and chert found in Kansas, Missouri, and Oklahoma. It overlies the Grand Falls Chert and is overlain by the Short Creek Oolite
Fossils: abundant fossils-corals, bryozoans, brachiopods, crinoid fragments and a few mollusks and trilobites
Upper Devonian limestone(?) found in Michigan. It overlies the Whiskey Creek Formation and is overlain by the Antrim Shale. It is equivalent to the Squaw Bay Limestone It is a member of the Traverse Group
Fossils: Marine invertebrates
150 to 300 meters or more of sparsely or non-fossiliferous Upper Ordovician red shales and sandstones found above the Martinsburg Shales and below Tuscarora Quartzites in Pennsylvania, Maryland, West Virginia, Virginia, and Tennessee.
Fossils: ichnofossils
Lower Devonian cherty Limestones of the Helderberg Group that overlie the New Scotland formation and are overlain by the Becraft formation.
Fossils: TBPL
400 meters of Middle Pennsylvanian coals,shales,sandstones found in Alabama(?),Virginia,and West Virginia. It overlies the Fayette sandstone/New River Group and is overlain by the Charleston Sandstone It is a member of the Pottsville Formation and is partially equivalent to the Breathitt Formation It is subdivided into Betsie Shale Member,Dingess Shale,Winifrede Shale, Bearwallow Sandstone, Chicken Ridge Sandstone,Homewood Sandstone. It also includes a number of coal beds -- Stockton (Mercer) Coal, Coalburg Coal, Winifrede Coal, Chilton Coal, Williamson Coal, Cedar Grove Coal, Peerless Coal, Campbell Creek Coal, Powellton Coal, Eagle Coal, Gilbert Coal, Douglas Coal, Montevallo Coal, Dogwood Coal, Maylene Coal, Kennedy Coal, Bearwallow Coal, Big Fork Coal, Lower Banner Coal, Upper Banner Coal, and Splash Dam Coal.
Fossils: Plants
As much as 25 meters of fossiliferous Middle Devonian concretionary shale, mudstone, sandstone and minor limestone found in Western and West Central New York. It overlies the Menteth Limestone/Portland Point Limestone and is overlain by the Windom Shale. It is a member of the Moscow Shale of the Hamilton Group.
Fossils: Sometimes abundant corals,brachiopods,bryozoa,trilobites,crinoids, and bivalves
Non-marine Upper Devonian continental deposits containing some plant fossils found in East Central New York above the Hamilton interval. It is divided into the Stony Clove Sandstone and the Wittenberg Conglomerate.
Fossils: TBPL
Upper Devonian North Central New York -- given that it is present in Chenango County, presumably marine shales,siltstones, and/or sandstones deposited in the rapidly filling "Catskill Delta" (Now thought to be a Forearc Basin). It is a member of the Sonyea Group. I was unable to find much information and suspect a spelling error, but this is the spelling used by USGS in GEOLEX.
Fossils: Unknown
Upper Devonian marine shales found in Wisconsin above the Milwaukee Formation. Antrim Shale in modern usage. Fossils: See Antrim Shale
A fossiliferous Lower Mississippian cherty, crinoidal limestone found in Illinois, Iowa, Kansas, Kentucky, Missouri, Nebraska, Oklahoma, and Tennessee. It overlies the Burlington Limestone and is overlain by the Warsaw Shale. It has been subdivided into the Archimedes Limestone (Obsolete)/Palestine Sandstone,St Genevieve Limestone,Warsaw Limestone,Pitkin Limestone,Grand Falls Chert, [Joplin Limestone (Obsolete)#Joplin],Montrose Chert,Peerless Park,Short Creek Oolite
Fossils: Abundant bryozoa, corals, blastoids, and brachiopods. Others
1200 meters of igneous beds capped with 1200 meters of detrial proterozoic beds dating to about 1000,000.000 Ma found in Michigan (Upper Peninsula), Wisconsin(ne) and Minnesota(ne). The top of the formation is not exposed, but it is presumably overlain by Paleozoic beds
Fossils: Possibly a few monocellular fossils in a few beds
Up to 50 meters of coarse grained crinoidal marine limestone found in Arkansas,Missouri,Kansas,Illinois,Indiana. It overlies the Plattin Limestone/Decorah Formation and is overlain by the Fernvale Limestone. It is sometimes treated as a group including the Dunleith Formation,Wise Lake Formation,and Dubuque Formations. It is a member of the Galena Group
Fossils: Abundant and diverse - corals, bryozoans, brachiopods, trilobites, crinoids, and mollusks
Up to 33 meters of highly fossiliferous Middle Ordovician grainstone limestones interbedded with very thin fossiliferous black shale layers. It overlies the Napanee Limestone of the Trenton Group and is overlain by the Sugar River Formation of the Trenton Group. It is equivalent to the Hull and Kirkfield formations in Ontario.
Fossils: TBPL
Highly fossiliferous Middle Ordovician grainstone limestones interbedded with very thin fossiliferous shale layers. It is found in Southwestern Quebec and Adjacent New York. It overlies the Napanee Limestone of the Trenton Group and is overlain by the Sugar River Formation of the Trenton Group. It is equivalent to the Kings Falls Formation in New York.
Fossils: TBPL
An Upper Silurian Hematite/Limestone found in upstate New York and adjacent Ontario. It is part of the Clinton Group It overlies the Dawes Sandstone and is overlain be the Herkimer Sandstone.
Fossils: Fragmentary marine invertebrates.
Up to 800 meters of non-marine Middle Devonian redbed deposits containing some plant fossils found in East Central New York in the Hamilton interval. It is overlain by Upper Devonian non-marine sediments of the Catskill Group.
Fossils: TBPL
Roughly 34 meters or more of unfossiliferous Upper Devonian or Lower Mississippian shale with two 3 to 6 meter conglomerate beds found in West Central New York where it overlies the Oswayo formation and underlies the Olean Conglomerate.
Fossils: TBPL
Up to 1300 meters of sometimes fossiliferous Upper Cambrian and Lower Ordovician dolomites and limestones found from Illinois to the Virginias and South to Mississippi, Alabama and Georgia. It overlies Cambrian shales Coosa/Conasauga/Nolichucky/Potsdam, Limestones Maynardville/Chances Branch, and sandstones Galesville. It is overlain by various Middle Ordovician limestones Trenton/Stones River Group/Murfreesboro/Chickamauga/Pelham/Eau Claire] or sandstones St Peter. Where it is subdivided, formations ascribed to the Knox Dolomite include : Copper Ridge dolomite, Chepultepec dolomite, Longview dolomite, Kingsport limestone, Mascot dolomite, Newala Dolomite, Lambs Chapel Dolomite, Potosi Dolomite, Oneota, Shakopee Dolomite, Everton dolomite, Odenville Limestone Bonneterre Formation, Davis Formation, Derby Formation,Doe Run FormationEminence Dolomite,Gasconade,Roubidoux Formation,Jefferson City,Cotter Dolomite,Powell Dolomite,Smithville Dolomite,Rose Run Sandstone
Something called the Knox Megagroup has been used in Kentucky consisting of the Knox Group (above) plus some underlying(?) sandstones Franconia, Potosi, Eminence, and Gunter
Fossils: Cambrian and Ordovician marine fossils in some beds -- see the entries for the individual formations.
Up to 100 meters of calcaerous Upper Ordovician shale and minor limestone found in Southwest Ohio as well as adjacent Indiana and Kentucky. It overlies the Clays Ferry or Point Pleasant members of the Cynthiana Limestone. It is overlain by the Fairview Limestone/Dillsboro Formation. It includes the Fulton/Economy/Southgate/McMicken shales of the Cincinnati area. It corresponds roughly to the Eden Group of earlier authors. It is a member of the Cincinnati Group
Fossils: Abundant, well preserved, Upper Ordovician fossils - Bryozoa,Brachiopods,crinoids,trilobites,bivalves
10 to 20 meters of pebbley Upper Devonian sandstone embedded in 60 to 160 meters of sandstone, shale and siltstone in Northwest Pennsylvania. It overlies the Delaware River Flags and underlies the Montrose Shale/Poplar Gap Formation/Packerton Formation. The Lackawaxen was originally described as belonging to the Chemung Group (generally marine) but was later assigned to the Catskill Group (generally non-marine).
Fossils: Unclear. Possibly some Chemung type marine invertebrates?
Perhaps 30 meters of possibly fossiliferous Upper Devonian marine shales and siltstones found in Southwestern New York lying above the Gowanda Formation and below the Westfield Shale. The Laona is a member of the Canadaway Group.
Fossils: Unclear, Ammonites have been found in beds that might be as young as the Laona or Westfield
A thin bed of pyrite/marcasite material found in Western New York where it separates the Windom Shale member at the top of the Middle Devonian Moscow Formation from the Geneseo Shale of the Upper Devonian Genesee Group. In some areas, two thin limestones, the North Evans Limestone and Genundewa Limestone may occur below or instead of the Leicester bed.
Fossils: brachiopods, mollusks, echinoderms and crustaceans.
80 meters of Lower Ordovician limestone or dolomite found in Tennessee and Virginia. It overlies the Longview Dolomite and is overlain by the Mascot Dolomite The Kingsport is apparently pretty much identical lithogically to the Mascot from which it is separated by 20cm of cherty sandstone. In areas where the separating bed is missing, the Mascot/Kingsport is interval is assigned to the LambsChapel or Newala formations Fossils: Exceedingly rare
A Middle Silurian gray sandstone found at the top of the Silurian Medina Group in West Central New York. It is separated from the similar Thorold Sandstone by the Cambria Formation. The Kodak Sandstone is overlain by basal Clinton Group formations -- the Maplewood Shale and the Furnaceville Hematite.
Fossils: uncommon - Astrophycus reported
An obscure Lower Ordovician Dolomite found in the SouthEastern(?) US. It overlies the Chepultepec Formation and is overlain by Chazy Age Middle Ordovician limestones. It is equivalent to the Longview-Kingsport-Mascot Dolomites. Fossils: Unknown
| Pennsylvanian,Upper | shale? | IA,KS,MO,NE | Pillsbury Shale | fossils: | GEOLEX link | NO cgkn link |
|---|
Six to Eight meters of pure crystaline Middle Ordovician Limestone found in the Champlain Valley of New York and Vermont. It overlies the Isle la Motte Limestone and is overlain by the remainder of the Glens Falls Limestone of which it is a member.
Fossils: Ordovician marine invertebrates
about 13 meters of hard, crystalline Middle Silurian dolomite interbedded with softer beds found in Indiana,Kentucky,Tennessee,Ohio,Illinois(?), and Missouri. Overlies the Osgood Shale which was included in the Laurel in early work. It is overlain by the Waldron Shale/Geneva Limestone. Attributed in some places to the Wayne Formation, Bainbridge Formation, Alger Formation, or Salamonie Dolomite. Not to be confused with the Cambrian age Laurel Granite in Maryland and the District of Columbia
Fossils: Often sparse. Some beds are moderately fossiliferous. Well preserved trilobites found near the top of the formation in some exposures. (In very hard rock).
A term for (some?) Chazy limestone beds in Quebec.
Fossils: TBPL
Up to 60 meters of highly fossiliferous Lower Middle Ordovician Stones River Group limestones found in Tennesee and adjacent Georgia. They overlie the Ridley Limestone and are overlain by the Carters Limestone/Nashville Group.
Fossils: abundant Black River age Ordovician marine fossils
Up to 30 meters of fossilifersous dirty Ordovician limestone and shale found in Georgia, Alabama, Tennessee, and Kentucky. The Leipers Limestone overlies the Catheys Limestone/Inman Formation and is overlain by the Fernvale Formation/Sequatchie Formation
Fossils: Abundant, diverse, Upper Ordovician marine fossils
Up to 200 meters of shaly early Middle Ordovician Limestone found in Georgia, Alabama, Tennessee, and Virginia. The Lenoir Limestone overlies the Knox Dolomite/Mosheim Limestone and is overlain by the Lebanon Limestone/Holston Formation
Fossils: Ordovician Chazy age marine fossils
An obsolete term for a portion of the Middle Ordovician limestones found at the top of the Black River Group (Selby Formation). It was used for rocks exposed West and South of the Adirondack Mountains in New York and Ontario.
Fossils: TBPL
The fossiliferous lowermost member of the Middle Silurian Rochester Shale between Hamilton, Ontario and Brockport, New York. 8 meters or so of shale, mudstone, and Limestone. It overlies the Irondequoit Limestone and is overlain by the Burleigh Hill/Gates Dolomite member of the Rochester Shale.
Fossils: abundant brachiopods, bryozoa, crinoids in fossiliferous lenses.
Up to 100 meters of fossiliferous Middle Ordovician limestones and claystones found in central Kentucky and overlapping into adjacent Indiana and Ohio. It is basically the same as the older Cynthiana Limestone of older authors. It overlies the High Bridge Limestone/Black River Limestone and is overlain by the Flanagan Chert/Point Pleasant Limestone/Clays Ferry Formation. It has been subdivided into a number of formations - Curdsville Limestone, Logana Limestone, Grier Limestone, Perryville Limestone, Brannon Formation, Sulphur Well Formation, Tanglewood Limestone, Devils Hollow Formation, Millersburg Limestone, and Nicholas Limestone. The Lexington is time equivalent to the Trenton and Reedsville limestones of the NorthEast.
Fossils: abundant, diverse fossils in often very hard limestone.
up to 11 meters of fossiliferous Upper Ordovician clay and limestone found in Southwest Ohio, and Indiana. The Liberty overlies the Waynesville Formation. It is overlain by the Whitewater Formation. It is a member of the Richmond Group.
Fossils: Marine invertebrates are common, well preserved, and abundant.
20 to 30 meters of Fossiliferous brown Chazy age Middle Ordovician limestone found in Virginia, West Virginia and Tennessee. It typically overlies the Five Oaks Limestone and is overlain by the Ward Cove Limestone.
Fossils: TBPL
Richly fossiliferous, dark, fine-grained Middle Ordovician limestones found in Eastern Ontario and Northwest Quebec. Corresponds to the upper part of the Trenton Limestones in the US. The uppermost beds are known as the Cobourg Formation in SouthEast Ontario and as the Eastview member in the Ottawa area. The Lindsay overlies the Trenton age Verulam Formation and is overlain by the Trenton Age Blue Mountain Formation in Southern Ontario and the Billings Formation in the Ottawa area.
Fossils: TBPL
As much as 100 meters of sparsely fossiiferous Upper Cambrian dolomite found in the Mohawk Valley of New York in the vicinity of Little Falls. It overlies the Hoyt Limestone and is typically overlain unconformally by the Ordovician Tribes Hill or Amsterdam formations.
Fossils: TBPL
Fossiliferous Upper Devonian marine shale, sandstone, and siltstone found in North Central Pennsylvania where it overlies the Brallier Formation and is overlain by the Irish Valley memberof the Catskill Group. It is a member of the Susquehanna Group.
Fossils: Brachiopods, ichnofossils, plants
As much as 50 meters of fossiiferous Middle Silurian dolomite found in Western New York and Ontario where it forms a conspicuous escarpment. The Lockport is the cap rock at Niagara Falls. The Lockport overlies the Rochester Shale of the Clinton Group and underlies the shales and limestones of the Upper Silurian Salina Group. The Lockport has been subdivided into the Decew dolomite and Gasport Limestone which have been further subdivided by many authors.
Fossils: TBPL
Up to 300 meters or more of Lower Ordovician marine limestone and dolomite that overlie the Chepultepec Dolomite in Georgia, Alabama, Tennessee and Virginia. Some authors include it in the Kingsport Dolomite. It is overlain by the Kingsport Dolomite/LambsChapel or Newala formations
Fossils: Sparse -- some gastropods
about 100 meteres of fossiliferous Upper Ordovician marine black shales that overlie the Utica shales in portions of New York, adjacent Ontario and Quebec. In the Mississipi River drainage where the Lorraine is not exposed on the surface, it overlies the Utica shales and is overlain by the Oswego sandstone. In parts of New York and Canada, it may be overlain by younger Ordovician and Silurian formations instead of the Oswego
Fossils: TBPL
Up to 30 meters of sometimes dirty Middle Silurian limestone found in Indiana(se) and adjacent Kentucky. It overlies the Waldron Shale and is overlain by the Geneva Dolomite/Jeffersonville Limestone
Fossils: Abundant, diverse corals
As much as 22 meters of Middle Ordovician dirty red limestone and calcaerous mudstone found above the Chazy/Pamelia limestones around the Adirondack Mountains of New York, in adjacent Ontario and Quebec and South into Maryland and West Virginia. It is overlain by other members of the Black River Group, Trenton Limestones or Martinsburg shales.
Fossils: TBPL
40 meters of Middle Devonian Dolomite found in NorthWest Ohio, SouthEast Michigan and adjacent Ontario. It overlies the Sylvania Sandstone and is overlain by the Columbus Limestone. It is similar to and may be identical to the Amherstburg Dolomite. The Lucas is a member of the Detroit River Group.
Fossils: Present - corals, others?
Up to 80 meters fossiliferous Middle Devonian mudstone, siltstone and shale belonging to the Hamilton Group. The Ludlowville is separated from the underlying Skaneateles Shale by the Centerfield Limestone, and from the overlying Moscow Shale by the Tichenor Limestone. Ludlowville outcrops are found across Northern New York from the Finger Lakes region to Lake Erie.
Fossils: TBPL
About 100 meters of cherty Early Middle Ordovician shale and limestone found in Virginia and West Virginia. The Lurich overlies Beekmantown beds and is overlain by the Lincolnshire Limestone.
Fossils: Present. Abundant in some beds, but overall abundance is not known.
94 meters of Upper Devonian near shore shales siltstones and thin sandstones found in the upper Canadaway Group in Western New York. The Machias overlies the Rushford Formation and is overlain by the Conneaut Group. It appears to occupy the same stratiagraphic interval as the NorthEast Shale.
Fossils: Marine fossils in shell beds in the sandstones, occasional ichnofossils
| 95m | Pennsylvanian,Upper | shale,sandstone | MD/OH/PA | ? | Brush Creek Limestone | equivalents | fossils:plants(abundant) | GEOLEX link | NO cgkn link | Glenshaw,Conemaugh |
|---|
Up to 225 meters of Upper Devonian siltstone and sandstone with minor shale found in Virginia, West Virginia, Maryland and Pennsylvania. It overlies the Scherr Formation and is overlain by the Briery Gap Formation. It is the basal member of the Foreknobs/Greenland Gap Formation/Group.
Fossils: Brachiopods - Ambocoelia, Devonochonetes, Tylothyris, Douvillina
Upper Silurian and Lower Devonian dolomites and limestones of the Helderberg Group found in the Eastern Lake Ontario plain, East to Albany then South to New Jersey. It overlies the Roundout Formation And is overlain by the Coeymans Formation.
Fossils: Stromatolites, bivalves, gastropods, corals, conodonts, tentaculites
Up to 30 meters of Lower Silurian dolomite found near the base of the Medina Group. It is found in Western New York and adjacent areas as far West as the Upper Peninsula of Michigan. In New York and Ontario it roughly corresponds to the Jolley Cut Dolomite.
Fossils: Dolomitized bioherms containing brachiopods, acritarchs, bryozoa
Fossiliferous Middle Devonian coastal plain deposits of shale,sandstone,siltstone found in East Central New York. It is laterally equivalent to the marine Moscow Shale further West. It is overlain by the marine Oneonta formation.
Fossils: TBPL
7 meters or so of unfossiliferous Middle Silurian marine green shale found in West central New York. It overlies the Medina Group Kodak Sandstone/Cambria Shale. It is overlain by the Reynales Limestone. It is laterally equivalent to the Neahga Shale] further West and is included in the Neahga]
Fossils: sparse
Up to 330 meters of thin black occasionally folliliferous Middle Devonian black shale with a few thin limestones. The Cherry Valley limestone is sometimes recognized as a formation or a member within the Marcellus separating two black shale members, the older Mount Marion and the younger Oatka Creek. The organic rich Marcellus is the lowest member of the Hamilton Group. It overlies limestones of the Onondaga Group. And is overlain by the Stafford Limestone which is overlain by shales of the Skaneateles Formation. It is widely distributed in the Eastern United States South of the Mohawk River and West of the Applachian Front.
| Middle Devonian Stafford Limestone | ||
| MIDDLE DEVONIAN MARCELLUS SHALE | ||
| Western New York | Central New York | Catskill-Mohawk Valley |
| Oatka Creek | Cardiff-Pecksport | Mount Marion |
| Oatka Creek | Cardiff-Solsville | |
| Oatka Creek | Cardiff-Bridgewater | Otsego |
| Oatka Creek | Chittenango | Berne |
| Cherry Valley Limestone | Stony Hollow | |
| Union Springs shale/limestone | Stony Hollow | |
| Union Springs shale/limestone | ||
| Middle Devonian Onondaga Group Limestones | ||
Fossils: Generally sparse although marine fossils can be abundant in limestone beds and a few other localized beds. Crinoids(mostly casts), cephalopods, brachiopods, corals, conodonts, etc.
Perhaps as much as 10 meters of Upper Cambrian or Lower Ordovician calcerous sandstones and dolostones found in SouthWestern Quebec,SouthEastern Ontario, and adjacent New York where they overlie similar beds with different conodont faunas in the Nepean Formation.
Fossils: TBPL
500 to 1500 meters of mid to late Ordovician Shales and sandstones found throughout the Appalachian Region. The Martinsburg consists of calcaerous shales under shales under sandstones and corresponds roughly to the Trenton, Utica, Oneonta interval in New York. Some authors treat the Martinsburg as a group with a number of members Bushkill (PA*,NJ*,NY), High Point (NJ*,NY*), Jonestown (PA), Paxton Creek (PA), Pen Argyl (PA*), Ramseyburg (NJ*,NY*,PA*), Schoharie (NJ,PA), Shochary Ridge (PA), West Fairview (PA), Stickley Run (VA*,WV*) Dauphin (PA) In general, the Martinsburg overlies Black River age limestones and is overlain by the Upper Ordovician Juniata Formation
Fossils: Diverse, but generally not very abundant fossils corresponding the Trenton, Utica and Eden faunas.
200 meters of Lower Ordovician limestone or dolomite found in Tennessee and Virginia. It overlies the Kingsport Dolomite and is overlain by the Dot Formation/New Market The Mascot is apparently pretty much identical lithogically to the Kingsport] from which it is separated by 20cm of cherty sandstone. In areas where the separating bed is missing, the Mascot/Kingsport is interval is assigned to the LambsChapel or Newala formations Fossils: Exceedingly rare
About 80 meters of gray cherty Upper Cambrian limestone and dolomite found in Alabama,Georgia,Tennesee,and Virginia.. It overlies the Nolichucky Shale/Conasauga Shale and is overlain by the Copper Ridge Dolomite/Conococheague Formation. It is has two members, the upper Chances Branch Dolomite and the lower Low Hollow Limestone. It is considered to be a member of the Conasauga Group
Fossils: abundant stromatolites, cystid plates, trilobites in the basal beds
A quasi-obsolete term for fossiliferous Upper Ordovician shales with minor limestones found in the Cincinnati area of Ohio, Kentucky and Indiana. It overlies the Eden Group and is overlain by the Richmond Group. In modern usage Maysville is a biostratigraphical term rather than a formation or group of formations. The Mount Auburn, Corryville, Bellevue, Fairmount, Mount Hope are generally recognized within the Maysville. The term Maysville is used in various contexts over an area extending from Alabama to West Virginia to Indiana.
Fossils: Moderately fossiliferous with diverse, well preserved, Ordovician marine fossils.
20 meters of Middle Ordovician algal limestone with limestone pebbles embedded found in Virginia and West Virginia. It overlies the Benbolt Limestone It is overlain by the McGraw Limestone. Some authors include the McGraw Limestone in the McGlone.
Fossils: Abundant fossils in the upper layers. See
A somewhat obsolete term for 20 meters of fossiliferous, calcaerous Upper Ordovician Shale and limestone found in Southwest Ohio. It overlies the Southgate Formation It is overlain by the Mount Hope Formation. In modern usage, it is the Upper third of the Latonia Formation/Kope Formation. It is a member of the Cincinnati Group
Fossils: Very Abundant, well preserved, Upper Ordovician fossils - Bryozoa
35 meters of fossiliferous Upper Ordovician Shale and Limestone found in the Cincinnati area of Ohio and adjacent Kentucky. It overlies the Fairview Formation and is overlain by the Arnheim Formation It includes the Bellevue, Corryville, and Mount Auburn Formations. It is part of the Maysville Stage of the Cincinnati Group
Fossils: Very Abundant, well preserved, Upper Ordovician fossils - Bryozoa
Upper Devonian marine shale and sandstone found in West central New York where it overlies the Beers Hill Formation/Roricks Glen Shale and is overlain by the Gardeau Shale/Corning Shale. It is a member of the Rhinestreet Black Shale of the West Falls Group.
Fossils: Unknown. Probably sparse to non-existent
Up to 35 meters of sparsely fossiliferous Lowest Silurian sandstones,shales,and phosphates. It is subdivided into number of thin formations: Whirlpool Sandstone (base), Jolley Cut Formation, Power Glen Shale, Balls Falls Formation, Devils Hole Sandstone, Grimsby Formation, Thorold Sandstone, Neahga Shale, Cambria Shale, and Kodak Sandstone. The Medina is found along the line of the Niagara escarpment in NorthWest New York and adjacent Ontario where it overlies the Queenston Shale and is overlain by the Clinton Group.
Fossils: TBPL
| Lower Silurian Clinton Group | |
| LOWER SILURIAN MEDINA GROUP | |
| WESTERN NEW YORK | CENTRAL NEW YORK |
| Kodak | |
| Thorold | Grimsby |
| Grimsby | |
| Upper Cabot Head | Grimsby |
| Power Glen-Whirlpool | |
| Manitoulin-Whirlpool | |
| Whirlpool | |
| Upper Ordovician Queenston | |
Lower Pennsylvanian shale found in Pennsylvania. It overlies the Connoquenessing sandstone and is overlain be the Tionesta sandstone/Homewood sandstone. It is a member of the Pottsville Group
Fossils: Plants
One meter of dirty Lower Silurian limestone with shale partings, chert, phosphate and pyrite found in Ontario in the Niagara Region. It is a member of the Clinton Group. It overlies the Reynales Limestone, Neahga Shale or the Thorold Sandstone] and is overlain by the Williamson Shale or Rockway Dolomite.
Fossils: Abundant brachiopods-Pentameroides. Crinoids
As much as 25 meters of Upper Devonian black shale found at the base of the Sonyea Group in Western New York and other states in the Appalachian Basin. It overlies shales of the Genesee Group and is overlain by the Cashaqua Formation. It is laterally equivalent to the basal Enfield Formation further East.
Fossils: Rarely marine fossils
An Upper Devonian marine black shale formation found at the base of the West Falls Group of South Central New York where it may be treated either as an independant formation of as a member of the Rhinestreet Black Shale. It overlies the uppermost Sonyea Group and is overlain by the Beers Hill Formation of the Rhinestreet Shale
Fossils: Possibly in sandstone layers within the shale. Fossils other than very occasional fish are rare in the shales of New York Devonian black shales.
Up to 300 meters of often red Middle Ordovician limestone and mudstone found in Virginia, Tennessee, West Virginia and Georgia. Is a transition unit from pure limestones below to shales above. Depending on the region, the underlying formation may be the Chickamauga Limestone (TN,VA),Lowville Limestone(VA), Lebanon Limestone(GA), Knox Dolomite (GA),Ottosee Shale(TN),Ridley Limestone(GA),McGlone Limestone (WV),Witten Limestone(TN/VA). The overlying unit may be the Sevier Shales(TN,VA), Eggleston Limestone(OH,WV),Bays Limestone(GA,TN),Martinsburg Shale(TN,VA). The Moccasin is generally considered to be part of the Chickamauga Group.
Fossils: Some parts are fossiliferous
An Upper Devonian black marine shale found at the base of the Sonyea Group in Central New York. It overlies shales of the Genesee Group and is overlain by gray mudstones of the Johns Creek Formation. It is laterally equivalent to the lower part of the Middlesex Formation further West.
Fossils: Unknown
nonmarine? Upper Devonian beds NorthEastern Pennsylvania where they overlie the Lackawaxen Conglomerate. Also called the Damascus Red Shale or Duncannon Formation it is the easterly, terrestrial, equivalent of the Wellsville Sandstone. It is a member of the Catskill Group.
Fossils: fish and plants (rare?)
Roughly 3 meters of fossiliferous Middle Devonian limestone found in New York and Pennsylvania. It is a member of the Onondaga Group. Generally consists of massive fine grained limestones with some shaly partings and chert in the upper beds. It overlies massive shaly Nedrow limestones and is overlain by the Seneca Formation.
Fossils: TBPL
An Upper Devonian marine black shale formation found at the base of the West Falls Group of Western New York where it may be treated either as an independant formation of as a member of the Rhinestreet Black Shale. It overlies the Rye Point Stream Formation/West Danby Formation and is overlain by gray Angola Shales.
Fossils: probably not. Fossils other than very occasional fish are rare in New York Devonian black shales.
Up to 120 meters of fossiliferous Middle Devonian mudstone, siltstone, limestone and shale belonging to the Hamilton Group. The Moscow is separated from the underlying Ludlowville Shale by the Tichenor Limestone, and from the overlying Upper Devonian Genesee Group by the Tully Limestone. Moscow outcrops are found across Northern New York from the Finger Lakes region to Lake Erie.
Fossils: TBPL
Several meters of Upper Cambrian sandstone resembling the older Potsdam formation from which it is separated by the Little Falls Dolomite and Hoyt Limestone. Found in scattered exposures West of Saratoga, NY. It is considered to be the basal member of the Gailor Formation.
Fossils: TBPL
up to 15 meters of fossiliferous Upper Ordovician shale and minor limestones found in Southwest Ohio. The Mount Aubrun overlies the McMillan Formation/Corryville Formation. It is overlain by the Arnheim Formation. It is a member of the Maysville Group. The Mount Auburn may be treated as the uppermost member of the Grant Lake Shale
Fossils: Marine invertebrates are common, well preserved, and abundant.
Black, organic rich shale and sandstone with occasional Middle Devonian fossils found in New York along the Catskill front. The organic rich Marcellus is the lowest member of the Hamilton Group. The Mount Marion is the highest member of the Marcellus in the Catskills and Mohawk Valley. It overlies the Solsville member and is overlain by the Ashokan beds.
Fossils: corals, brachiopods, gastropods
An assemblege of silaceous Ordovician shale with substantial amounts of chert found near the top of the Taconic Terrane sequence in Eastern New York as well as in isolated blocks in the melange belt of the Hudson River Valley where large blocks of Middle and Upper Ordovician marine rocks hundreds or thousands of meters on a side are jumbled together.
Fossils: farily abundant graptolites in some outcrops
An obscure Upper Devonian(?) redbed sandstone found in NorthEastern Pennsylvannia. It is a member of the Catskill Group. There is a Mississippian age Mt Pleasant Sandstone in Indiana.
Fossils: Unknown
Up to 120 meters of masive cherty Late Lower Ordovician Limestone with occasional shales recognized in Georgia, Tennessee and Virginia. It overlies the Newala Limestone and is overlain by the Pierce Limestone. It is considered to be a member of the Stones River Group/Chickamauga Group
Fossils: sparse and difficult to extract. brachiopods, trilobites, others?
13 meters of blue-gray fossiliferous Middle Ordovician limestones interbedded with very thin fossiliferous black shale layers. It is the oldest formation in the Trenton Group. It has also been included in the Rockland formation. It is found in the Mohawk Valley and West of the Adirondacks in New York and adjacent Ontario.
Fossils: TBPL
Another in the bewildering assortment of Upper Devonian marine shales,siltstones, and sandstones found in Western New York. Apparently a deep water clastic formation in theWest Falls Group
Fossils: Apparently fairly abundant -- brachiopods-ammonites.
About 110 meters of Middle/Upper marine Ordovician limestones with minor shales found in Alabama, Georgia and Tennessee. It overlies the Stones River Group and is overlain by the Harpeth Group/Tennessee Group/Inman Formation/Sequatchie Formation. It is subdivided into the Hermitage Formation, Cannon Limestone, and Catheys Formation. It is laterally equivalent to the Lexington Limestone, Clays Ferry Formation, and Kope Formations and is treated as a member of the Chickamauga Group
Fossils: Abundant, well preserved, Ordovician marine fossils
Two meters of fossiliferous green shale found at the base of the Silurian Clinton Group in the Niagara Gorge and adjacent New York and Ontario. The Neahga is overlain by the Hickory Corners Limestone #HickoryCorners and overlies the [Thorold Sandstone of the Medina Group.
Fossils: Conodonts,brachiopods
Roughly 4 meters of fossiliferous shaly Middle Devonian limestone found in New York and Pennsylvania. It is a member of the Onondaga Group. Generally it overlies massive Edgecliff formation limestones or Esopus formation clastics and is overlain by more massive limestones of the Moorehouse Formation.
Fossils: TBPL
30-50 meters of limy Early Devonian shales and very minor limestones found Pennsylvania, Maryland, Virginia and West Virginia. Overlain by Selinsgrove Limestone and overlies Oriskany Sandstones
Fossils: brachiopods, crinoids, styliolines, and cephalopods
Upper Cambrian or Lower Ordovician sandstones found in Southern Ontario and SouthWestern Quebec where they are the oldest formation of the Paleozoic sequence. They are equivalent to the Potsdam Sandstone in the United States, but are thought to be somewhat younger than the Potsdam in most places as it is assumed to result from the Iapetus sea slowly enroaching over the continental platform from the SouthEast.
Fossils: TBPL
30 to 90 meters of Upper Devonian and Lower Mississippian dark or black marine shales found in Indiana, Ilinois and Western Kentucky. The New Albany overlies Middle Devonian limestones and is overlain by a variety of Mississippian formations. In some areas, it is subdivided into a number of shale, limestone, and sandstone units.
Fossils: plants, fish, marine invertebrates, ichnofossils
340-490 meters of Upper Devonian shale and sandstone found in South Central New York and adjacent Pennsylvania where it occupies the interval occupied by the West Falls Group further West. It overlies the Gardeau Formation is part of the Susquahanna Group.
Fossils: Unknown. Probably few or none
Lower Devonian shaly Limestones of the Helderberg Group that overlie the Coeymans formation and are overlain by the Becraft or Kalkberg formations.
Fossils: TBPL
Up to 300 meters of Lower Ordovician Limestone and occasionaly dolomite found in Alabama, Georgia, Kentucky and Virginia. It overlies the Longview Limestone and is overlain by the Odenville Limestone/Murfreesboro Limestone/Rockmart Slate/Lenoir Limestone. It is laterally equivlent to the Kingsport and Mascot Limestones. considered to be a member of the Knox Group
Fossils: A few gastropods, conodonts
Middle Devonian shaly Limestones occupying the Onondaga Limestone interval in South Central Pennsylvania. Overlies Lower Devonian beds and is overlain by the Marcellus Shale.
Fossils: Unknown
An obsolete(?) term used in the 19th and early 20th century for Middle Silurian rocks in Tennessee, Kentucky and the Middle West.
Fossils: Almost certainly present in many beds.
Up to 250 meters fossiliferous calcearous shales and shaly Upper Cambrian limestones Alabama,Georgia,Tennesee,Kentucky, West Virginia and Virginia.. It overlies the Maryville Limestone and is overlain by the Knox Dolomite/Maynardville Limestone/Gatesburg Formation. A persistent limestone bed in the middle of the formation is sometimes identified as the Bradley Creek Limestone THe Nolichucky is considered to be a member of the Conasauga Group
Fossils: At least 30 species of fossils -- mostly trilobites and brachiopods.
Upper Devonian grey marine shales with minor siltstone found in the upper Canadaway Group in Western New York and Pennsylvania. The Machias overlies the Rushford Formation and is overlain by the Conneaut Group. It appears to occupy the same stratiagraphic interval as the Machias Formation.
Fossils: Said to contain a sparse marine fauna
Exposures of mostly unfossiliferous Middle to Upper Ordovician black shales,sandstones and brown shales found in New York on both sides of the Hudson River from Kingston to Saratoga. Strictly speaking, it is not a formation but rather a melange of large blocks of countryside stacked up on the margin of the Paleozoic continent of Laurentia when the Iapetus Sea closed in the late Ordovician. Unlike a normal formation, there are no overlying and underlying strata. There are two facies -- a black shale facies termed the Normanskill Formation and a shale and sandstone facies called the Austin Glen Formation.
Fossils: Occasional graptolites. Rarely, A few shelly fossils in turbide beds
A thin limestone (a few cm) containing fish and crinoid fragments and conodonts found at the base of the Upper Devonian Genesee Group in Western New York. The North Evans overlies the Hamilton Group Windom Shale member. It is overlain by the Genundewa Limestone
Fossils: tiny crinoid fragments,fish teeth,conodonts,styolines
Upper Devonian marine shales of the Venango Formation of the Conewango Group found NorthWest Pennsylvania where they overlie the Bimber Run Congloerate and are overlain by the Oswayo Formation? of Woodcock Sandstone
Fossils: Unknown. Probably Present. Possibly abundant
70 meters of Upper Devonian marine sandstone of the West Falls Group found in Western New York and South into Pennsylvania. It overlies Gardeau Shales/West Hill Shales and is overlain by the Wiscoy Formation Shales and Sandstones. The Name Nunda was originally proposed as a replacement for the term Portage.
Fossils: Some marine fossils
Dolomitic Middle Silurian Limestone found in Western New York where it overlies the Devils Hole Dolomite and underlies the Oak Orchard Dolomite
Fossils: Lockport age invertebrates present. Abundance and condition unclear.
An obsolete term used 45 meters of rocks now assigned to the Guelph and Eramosa formations in Western New York and adjacent Ontario. It overlies the Goat Island Dolomite/Oakfield Limestone. It is overlain by the Vernon Shale
Fossils: stromatoporoids, corals, stromatolites, conodonts, others(?)
Black, organic rich shale and sandstone with occasional Middle Devonian fossils found in Western New York in a strip South of and parallel to Lake Ontario. The organic rich Marcellus is the lowest member of the Hamilton Group. In Western New York, the Oatka Creek Formation constitutes all the Marcellus Shale above the Cherry Valley Limestone It is overlain by the Stafford Limestone.
Fossils: sparse?
15 meters of impure, cherty, Lower Ordovician dolomite and limestone exposed in Alabama. It overlies the Newala Limestone and is overlain by the Mosheim limestone. It is a member of the Knox group
Fossils: Beekmantown Age marine fossils- lithistid sponges, brachiopods, cephalopods, gastropods, trilobites.
Lower Ordovician limestones, sandstone, shales, mudstones exposed in Northernmost New York and adjacent Ontario and Quebec. The lowest member of the Beekmantown Group in Canadian nomenclature?
Fossils: TBPL
100 meters or more of Upper Devonian black shale found in Ohio, Pennsylvania, Kentucky, West Virginia Virgina and Tennessee. The numerous clastic beds found further East converge into the Ohio. It has been divided into four members -- the Huron Shale, the Three Lick Beds (mostly in the South), the Chagrin Shale (in the NorthEast), and the Cleveland Shale. The Ohio Shale overlies Middle Devonian Hamilton age limestones and is overlain by latest Devonian Bedford Shale.
Fossils: fish-sometimes articulated and abundant. Invertebrates in some beds
20 meters of Lower to Middle Pennsylvanian conglomerate found in a small area of Southern New York where it overlies the Lower Mississippian Pocono Group.
Fossils: TBPL
15 meters of bluish Upper Devonian marine shales found in Ohio, Indiana, Kentucky,Tennesee, and possibly Ontario. It overlies the Rhinestreet black shale/Delaware Limestoneand is overlain by the Ohio black shale
Fossils: Generally sparse, but moderately abundant in a few outcrops
A lower to middle Silurian sandstone and conglomerate found in Northern New York's Mohawk Valley where it overlies Upper Ordovician black shales It is roughly contemporaneous with the Medina Group further West.
Fossils: TBPL
Up to 430 meters of sparsely fossiliferous Middle and Upper Devonian fluvial mudstones,conglomerate,and sandstone found in Central New York. The Oneanta overlies Gilboa and Manorkill shales and. It is roughly equivalent in age to the marine Genesee Group and/or Sonyea formation further west.
Fossils: somewhat abundant fish fragments in some beds.
25 meters of hard sandy Lower Ordovician Dolomite found in Iowa,Illinois,Indiana,Michigan,Minnesota and Wisconsin. It overlies the Jordan Sandstone/Rountree Formation/St Peter Sandstone It is overlain by the Shakopee Dolomite/New Richmond Sandstone. It is assigned to the Knox Group or Prairie du Chein Group. It is laterally equivalent to the Gasconade Dolomite
Fossils: Conodonts, sponges, brachiopods, gastropods, crinoids, ichnofossils from the basal Blue Earth Siltstone member in Minnesota. Stromatolites
About 60meters of fossiliferous Lower Middle Devonian limestones with some shales found above Lower Devonian Oriskany/Esopus clastics and below black organic rich Middle Devonian Marcellus shales. The terminology is used throughout the NorthEast and includes a number of formations: Babcock Hill (NY), Buttermilk Falls (PA), Clarence (PA,NY*), Edgecliff (PA,NY*), Moorehouse (PA,NY*), Nedrow (PA,NY*), Selinsgrove Limestone (PA), Seneca (NY*), and Springfield Center (NY) Members of Onondaga Limestone Formation; Clarence Chert (PA), Columbus Limestone (OH,PA,WV), Delaware Limestone, Edgecliff Limestone (PA), Moorehouse Limestone (PA,NY), Needmore Shale (PA), Newton-Hamilton Formation (PA), and Selinsgrove Limestone (PA). The Onondaga more or less coincides with the "Corniferous" of 19th Century Geologists.
Fossils: TBPL
8 meters of fossiliferous shallow water Upper Ordovician shale,clay and limestone found in Southwest Ohio, and adjacent Kentucky. The Oregonia Formation is the uppermost member of the Arnheim Formation. It overlies the Sunset Formation and is overlain by the Waynesville Formation. It is laterally equivalent to the Dillsboro and Bull Fork formations.
Fossils: Marine invertebrates are common, well preserved, and abundant.
10 meters of Fossiliferous Lower Devonian sandstones found in Northern New York and adjacent Ontario where they unconformally overlie Upper Silurian dolomites or the Helderberg Limestones and underlie the Onondaga Limestones. The term is widely used the the Applachian area for Lower Devonian sandstones at the base of the Devonian sequence as much as 230 meters thick. They are often overlain by the coarser Esopus grit. Some Authors include the Oriskany and Esopus in a Tristates Group]
Fossils: spiriferid brachiopods and platycerid gastropods
A fossiliferous gray limestone of Middle Ordovician age found in the Champlain Valley of New York and Vermont where it Overlies the Trenton age Glens Falls limestone and is overlain by shaly beds of the Cumberland Head formation. It is probably time equivalent to the Rust formation in the Trenton Group.
Fossils: TBPL
10 meters of Middle Silurian shales,limestones,impure dolomites, chert found in Alabama, Tennessee, Kentucky, Indiana and Ohio. It overlies the Brassfield Formation/Dayton Limestone and is overlain by the Laurel Dolomite. In Indiana it is a member of the Salamonie Dolomite
Fossils: Said to be abundantly fossiliferous in places but preservation may be poor
Up to 83m of Fossiliferous, marine Upper Devonian shales found in SouthWestern New York and Northwestern Pennsylvania and Ohio. It overlies similar beds with conglomerate of the Cattaragus/Venango Formations and underlies the Pocono Group or recent sediments. It is the upper formation in the Conewango Group.
Fossils: fossils in sandstones interbedded with greenish shales
Up to 500m of fossiliferous Upper Ordovician sandstone with minor shale and conglomerate found in NY,PA,MD and Virginia. Where it lies between two shale units -- Lorraine-Martinsburg-Hudson River and Queenston-Juniata-Medina shales.
Fossils: TBPL
Up to 170 meters of Middle Devonian sandstone found in East Central New York where it overlies the Solsville member of the Marcellus Shale. It is overlain by the Chittenango member of the Marcellus Formation. It is a member of the Marcellus Formation and further East, it has been considered to be a member of the Mt Marion Formation and overlies the Berne member of the Mt Marion Formation.
Fossils: Abundant?
20 meters or so of Lower or Middle Silurian Sandstone from the Clinton Group found in New York. Fossils are limited to a few invertebrate tracks.
Fossils: TBPL
Fossiliferous Middle Ordovician marine beds found in Western Quebec and adjacent Eastern Ontario associated with a paleozoic marine feature known as the Ottawa Embayment. Corresponds to the Simcoe Group further West and the Chazy-Black River-Trenton sequence in the US. Overlies Beekmantown age beds of the Oxford Formation and includes the Pamelia,Lowville,Gull River,Bobcaygeon,Verulaum and Lindsay formations. The Ottawa is overlain by (or includes?) Upper Ordovician shales of the Billings and Carlsbad. The Ottawa Group contains abundant, diverse Middle Ordovician faunas in the upper beds.
Fossils: TBPL
| Upper Ordovician Carlsbad Formation Shale |
| Upper Ordovician Billings Formation Black Shale |
| ORDOVICIAN OTTAWA GROUP |
|---|
| EASTERN ONTARIO |
| Middle Ordovician ++Lindsay Limestones and Black Shales |
| Middle Ordovician ++Verulam Limestone |
| Middle Ordovician ++Bobcaygeon Limestone |
| Middle Ordovician ++Gull River Limestone |
| Middle Ordovician ++Lowville Limestone |
| Middle Ordovician +Pamelia Limestone |
| Middle Ordovician Rockcliffe Limestones and shales |
Up to 400 meters of Lower Ordovician Blount Group/Chickamauga Group shales and limestones found in Georgia,Tennessee, and Virginia. It overlies the Holston Marble/Tellico Sandstone/Athens Shale/Lenoir Limestone. It is overlain by Lowville Limestones
Fossils: TBPL
Up to 200 meters of slightly fossiliferous Upper Cambrian or Lower Ordovician dolostones found in SouthWestern Quebec,SouthEastern Ontario, and adjacent New York where they overlie the March Formation.
Fossils: TBPL
Marine Lower Ordovician dolomites and dolomite shales exposed occasionally in New York's Mohawk Valley. The Palatine Bridge is a member of the Tribes Hill Formation. It overlies dolomites of the Fort Johnson Member and is overlain by dolomitic limestones of the Wolf Hollow member
Fossils: ichnofossils
Up to 100 meters of nonmarine? Upper Devonian grayish alluvial plain sandstone and siltstone beds with some conglomerate found in NorthEastern Pennsylvania where they overlie the Lackawaxen Conglomerate/Poplar Gar Formation. They are overlain by the Long Run Formation. They are a member of the Catskill Group.
Fossils: Unknown. Quite possibly none
Roughly 15 meters of Dolomites shales and arkose found around the Adirondack Mountains of New York and in adjacent Ontario and Quebec where it is considered to be part of the Black River Group and/or Ottawa Group. It unconformally overlies Middle Ordovician Chazy limestones or Lower Ordovician Beekmantown Group rocks. It is overlain by the Lowville Formation.
Fossils: TBPL
An Uppermost Devonian conglomerate of waterworn quartz pebbles and sand found in the Cattaragus Formation and Venango Formation of Western New York and adjacent Pennsylvania.
Fossils: Abundant Ptychopteria in exposures in Pennsylvania.
As much as 850 meters of fossiliferous Middle Devonian shales, sandstone and limestone. It is a member of the Hamilton Group. It overlies black, organic rich Marcellus shales and is overlain by shales of the Moscow Formation. It is found above the Marcellus shales in North Central New York. It seems to be an Easterly equivalent of the Upper Marcellus, Skaneateles, and Ludlowville Shales.
Fossils: TBPL
A thin (15cm) but regionally persistent limestone found near the top of the Cashaqua Shale of the Upper Devonian Sonyea Group in Central New York east of Seneca Lake.
Fossils: Abundant cephalopods
"Passage Beds" is a largely 19th century term for transitional beds between two lithologies -- usually between major sequences. Which transition beds are intended has to be determined from context. Included here because it is sometimes used in contexts where it could easily be interpreted as a formation or group name.
An Upper Ordovician quartz and shale conglomerate within the Martinsburg Formation in the vicinity of Harrisburg, Pennsylvania.
Fossils: None?
Gray Middle Devonian shale found in East Central New York where it overlies the Solsville member of the Marcellus Shale. It is a member of the Marcellus Formation
Fossils: Brachiopods, gastropods -- not very diverse
As much as 17 meters of fossiliferous Middle Ordovician Black River age limestone found in Virginia and West Virginia where it overlies the Ward Cove Limestone it is overlain by the Benbolt Formation
Fossils: TBPL
Several tens of Middle Silurian dolomite of the Lockport Group found in West Central New York. It is thought to be in equivalent to the Goat Island Dolomite and Gasport Limestone further West. It is overlain by the Eramosa Dolomite and overlies the DeCew Dolomite.
Fossils: Unknown
An obscure Trenton Age formation found in Alabama. It overlies the Knox Dolomite
Fossils: Most "Trenton" rocks contain abundant, diverse, Middle Ordovician fossils.
1000m of Middle to Upper Ordovician marine Martinsburg black shale found in Northeastern Pennsylvania and adjacent New Jersey. It overlies the Ramseyburg Shale and is overlain by the Shawangunk Conglomerate.
Fossils: Sparse. Graptolites and a few shelly fossils have been recovered at scattered localities. Small Graptolite fragments have been reported from other outcrops.
As much as 45 meters of fossiliferous Upper Devonian marine shales interbedded with unfossiliferous flags found in Western New York and adjacent states near the base of the Genesee Group. The Penn Yann overlies the Geneseo Shale. It is overlain by the West River Shales
Fossils: Apparently fairly abundant Late Middle-Early Upper Devonian marine invertebrates.
As much as 130 meters of Upper Devonian sandstone,siltstone,shale found in Western New York and adjacent Pennsylvania and Ohio. It overlies the West Falls Group and is overlain by the Laona Sandstone. The Perrysburg appears to be roughly equivalent to the lower Canadaway Group including at least the Dunkirk Shale and Gowanda Formation.
Fossils: Sparse at best?
9 meters of thin bedded flaggy Early Ordovician Limestone with shale partings found in Tennessee. It overlies the Murfreesboro limestone and is overlain by the Ridley Limestone. It is a member of the Stones River Group
Fossils: Brachiopods and bryozoa - diverse.
8 meters or less of black, organic rich, Upper Devonian marine shale found from Western New York as far South as West Virginia. In New York, it separates the Java Shale, Hanover Shale,Wiscoy formations from the older Angola Shale and Nunda Formation. All these formations are members of the West Falls Group
Fossils: Unknown.
Black Silurian shales with interbedded thin dolomites exposed in the Erie Canal near Pittsford, NY. It overlies the Guelph Dolomite and is overlain by the Vernon Shale. It is amember of the Salina Group.
Fossils: Abundant Eurypterids, others
Up to 190 meters of fine grained marine limestone found in Arkansas,Missouri,Kansas,Illinois,Indiana. It overlies the Joachim Dolomite and is overlain by the Decorah Formation/Kimmswick Limestone. Sometimes treated as a group including the Mifflin Formation,Grand Detour Formation,Nachusa Formation,Quimbys Mill Formation.
Fossils: Abundant in some beds - corals, others.
Several hundred meters of fossiliferous marine Middle Devonian Hamilton Group shales and sandstones found in New York in the area immediately West of the Hudson River. The Plattekill underlies the similar non-marine Ashokan beds and overlies undifferentiated Hamilton Group sediments.
Fossils: Middle Devonian marine invertebrates
A Middle Devonian Shale found in NorthWest Ohio where it overlies the Delaware Limestone and is overlain by the Prout Limestone
Fossils: Abundant and diverse marine invertebrates
1000 meters or more of Uppermost Devonian-Lower Mississippian near-shore siltstone, sandstone, conglomerate and shale found primarily in Pennsylvania, but lapping over into adjacent areas. In New York, it is present only in the Southernmost areas where there is a single Knapp formation recognized.
Fossils: TBPL
An Uppermost Devonian marine conglomerate of waterworn quartz pebbles and sand several meters thick found in the Cattaragus Formation and Venango Formation of Western New York and adjacent Pennsylvania.
Fossils: sparse brachiopods-Spirifera, Ptychopteria
The term "Portage" is used as a "facies" term to identify the Upper Devonian deep water-marine equivalents of shallow water Portage facies found further East. The non-marine facies even further East are the Catskill facies. Further west, the equivalent beds are part of the Ohio Black Shales.
See Chemung Group.
Up to 60 meters of deepwater Lower Devonian Limestone found in the Catskill area of New York. It overlies Alsen Formation] or Becraft Formation beds and is a member of the Helderberg Group. It contains well preserved ichnofossils in clay nodules. It is overlain by Port Jervis limestones of the Tristates Group
Fossils: ichnofossils in clay nodules
Up to 30 meters of fossiliferous Lower Devonian marine limestone found in the Catskill area of New York, New Jersey and Pennsylvania as well as South Central Pennsylvania and adjacent Maryland and West Virginia. It overlies Port Ewen Limestone beds and is a member of the Helderberg Group. It is overlain by Ridgeley Sandstone or equivalents
Fossils: Brachiopods-Rensselaraeria;Trilobites-Dalmanites,Homalonotus
Up to 130 meters of Upper Cambrian dolomite interbedded with chert found in Arkansas,Missouri,Illinois,Indiana, and Oklahoma. It overlies the Doe Run Dolomite/Franconia Formation and is overlain by the St Peter Sandstone/Oneota Dolomite/Eminence Dolomite. It is considered to be a member of the Knox Group. It is laterally equivalent to the Equivalent to St Lawrence Dolomite/Trempealeau Dolomite
Fossils: stromatolites. Rarely gastropods and trilobites.
Up to 200 meters of Middle and Upper Cambrian sandstone and quartzite overlying a basal conglomerate. The formation can be found in an arc around the Eastern and Northern sides of the Adirondack uplift in New York. It probably laps over into a small area of Western Vermont. It then is exposed in an arc across Western Quebec and South West Ontario where it may be referred to as either the Potsdam or Nepean. The term Potsdam has also been applied to Middle and Upper Cambrian Sandstones in Michigan's Upper Peninsula, Minnesota and Wisconsin. It overlies ancient metasediments of the Grenville Group and is overlain by dolomitic sandstones of the Theresa Formation. Fossils are present, but uncommon, in the Potsdam of New York.
Fossils: TBPL
Lower to Middle Pennsylvanian terrestrial coal,siltstone, sandstone, conglomerate and shale found widely throughout the Appalachian Mountains. In New York, it is present only in a small area of South Central New York where there is a single Olean Conglomerate member recognized.
Fossils: TBPL
Up to 60 meters of Upper Devonian sandstone, siltstone, and conglomerate found in Virginia, West Virginia, Maryland and Pennsylvania. It overlies the Blizzard Formation and is overlain by the Red Lick Formation. It is a member of the Foreknobs/Greenland Gap Formation/Group.
Fossils: Brachiopods - Spinatrypa, Camarotoechia, Cyrtospirifer
A Lower Silurian marine shale with thin sandstone beds found near the base of the Medina Group. It is found in Western New York and adjacent Ontario as well as Appalachian areas as far South as West Virginia. It overlies the Jolley Cut Dolomite/Manitoulin Dolomite and is overlain by the Grimsby Sandstone
Fossils: Not abundant?: ichnofossils, Scoleodots, plants(?), crinoids(articulated), bivalves, starfish in the sandy layers
Roughly 170 meters of unfossiliferous greenish Upper Silurian dolomitic limestone and shale found in South Eastern, NY and adjacent Pennsylvannia. It is laterally equivalent to the Binnewater Sandstone. It overlies the Shawangunk Conglomerate/Bloomsburg Sandstone and is overlain by the Rondout Formation/Bossardville Limestone.
Fossils: Few or none.
Up to 65 meters of Lower Ordovician sandy dolomitic limestone found in Arkansas,Missouri,and Illinois. It has some complex interrelationship with the similar Smithville Dolomite and Black Rock Dolomite. It overlies the Cotter Dolomite and is overlain by the Everton Limestone.
Fossils: sparse, but gastropods, cephalopods, and trilobites have been reported
15 to 20 meters of silty, largely unfossiliferous, greenish Upper Ordovician mudstone with beds of dolomitic siltstone found in Kentucky Southwest of Cincinnati. It overlies the Rowland Formation and is overlain by the Brassfield Limestone. It is considered to be the upper member of the Drakes Formation.
Fossils: Few or none in the mudstones. Poorly preserved brachiopods and bryozoa in the dolomitic beds. Abundant and well presereved corals and stromatoporoids in some exposures in a limestone that separates the Preachersville from the underlying Rowland Formation
A Middle Devonian Limestone found in Northwest Ohio. It overlies the Plum Brook Shale and is overlain by the Olentangy Shale or Huron Shale.
Fossils: Corals
About a hundred meters of Lower Ordovician dolomite exposed in the Champlain Valley of New York and Vermont. Dated from a few fossils observed near Plattsburg, NY. Equivalent to the Older Beekmantown-E series and the Bridport Dolomite of some workers. Other source say it is the modern name for the obsolete Chipman Formation which includes several members besides the Bridport dolomite.
Fossils: Fossils: Localized Lower Ordovician marine fossils -- often fragmented
490 meters of fossiliferous mid to upper Ordovician siltstone,shale,and sandstone underlying the Oswego Sandstone in areas along the South shore of Lake Ontario where it interbeds with the similar Whetstone Gulf formation.
Fossils: TBPL
An Upper Devonian marine formation found in the upper Sonyea Group interval in Central New York where it is the oldest of three members corresponding to the Cashaqua Formation further West. It is overlain by the Rock Stream Member and overlies the Sawmill Creek Black Shale
Fossils: Unknown
About 60 meters of Upper Silurian dolomite found in Ohio and adjacent Michigan and Ontario. It overlies the Greenfield Dolomite and is overlain by the Raisin River Dolomite. It is a member of the Bass Islands Dolomite Group
Fossils: Unknown. Probably few or none
Uppermost Ordovician sparely fossiliferous red shales, gypsum, and occasionalthin limestones found above Oswego Sandstones and below Silurian redbeds. The Queenston formation is exposed in Northwestern New York and adjacent Ontario along the base of the Niagara escarpment. It is more or less equivalent to the Juniata formation in Pennsylvannia.
Fossils: TBPL
About 60 meters of Upper Silurian dolomite found in Ohio and adjacent Michigan and Ontario. It overlies the Put In Bay Dolomite and is overlain by the Detroit River Group. It is a member of the Bass Islands Dolomite Group
Fossils: Unknown. Probably few or none
900m of Middle to Upper Ordovician marine Martinsburg Shale found in Northeastern Pennsylvania and adjacent New Jersey. It overlies the Bushkill Shale and is overlain by the Pen Argyl Shale.
Fossils: Sparse. Graptolites and a few shelly fossils have been recovered at scattered localities. Small Graptolite fragments have been reported from other outcrops.
Upper Devonian marine siltstone,sandstone,and shale found in Western New York. It is a member of the Conneaut Group. It overlies the Cuba Formation and is overlain by the Wellsville or Hinsdale Formations.
Fossils: Unknown
Upper Devonian marine siltstones and shales found in East Central New York. It is a member of the Ithaca Formation of the Genesee Group. It overlies the Sherburne Formation and underlies the Sixmile Shale of the Ithaca Formation.]
Fossils: Brachiopods-Lingula
Up to 6 meters of very fossiliferous Lower-mid Silurian limestone exposed in NorthWest New York and adjacent Ontario where it overlies Clinton Group clastics and underlies other Clinton Group formations.
Fossils: TBPL
A few meters Upper Devonian marine black shale found in large parts of the Applachian Basin between the Cashaqua Shale below and the Angola gray mudstone above. It is an element of the Naples facies. It is a member of the West Falls Group.
Fossils: Rarely fish?
28 meters of Upper Devonian marine blue-gray shale of the Conewango Group found in Pennsylvania and West Virginia. It overlies the Venango Shale and is overlain by the Cussewago sandstone/Berea Shale
Fossils: Abundant
A quasi-obsolete term for 120 meters of fossiliferous Upper Ordovician shales with minor limestones found in the Cincinnati area of Ohio, Kentucky and Indiana. It overlies the Maysville Group and is overlain by Silurian beds. In modern usage Richmond is a biostratigraphical term rather than a formation or group of formations. The Elkhorn, Whitewater, Salada, Liberty, Waynesville, Arnheim are generally recognized within the Richmond. The term Richmond is used in various contexts over an area extending from Alabama to West Virginia to Missouri.
Fossils: Abundantly fossiliferous with diverse, well preserved, Ordovician marine fossils.
Up to 80 meters of fossiliferous Lower Devonian calcaerous sandstone and sandy limestone found in Maryland, Pennsylvania, New Jersey,West Virginia and Virginia. It is the uppermost member of the Oriskany Group. It overlies the Shriver Chert and is overlain by the Romney Formation/Esopus Grit
Fossils: abundant silicified brachiopods in weathered sandstone.
30 meters of fossiliferous Middle Ordovician marine Limestone of the Stones River Group found in Georgia and Tennessee. It overlies the Pierce Limestone and is overlain by the Glade Limestone
Fossils: Brachiopods,Bryozoa.
13 meters of uppermost Cambrian or lowest Ordovician limestone exposed in the neighborhood of Saratoga Springs, NY. It overlies the Little Falls Dolomite and is considered by some to be a member of the Gailor formation. Fossils include trilobites including taxa that elsewhere are considered to be diagnostic of the Upper Cambrian.
Fossils: TBPL
A somewhat obsolete term for 100 meters of richly fossiliferous Middle Ordovician alternating shales and thin (6 to 12cm) limestones found in Ohio, Indiana, Kentucky and Tennessee in a broad area surrounding the Cincinnati Arch. It is often referenced in other areas of the Central US. From oldest to youngest, it consists of the Arnheim Shale, the Waynesville Shale, the Liberty Limetone, Saluda Limestone], the Whitewater Shale, and the Elkhorn Limestone. It overlies the Mt Auburn shale of the Maysville Group and is overlain by poorly fossiliferous red mudstones of the Drakes Formation
Fossils: abundant and diverse. Many of the limestones are fossil coquinas
Fossiliferous Late Lower Devonian marine beds found in Eastern New York. Treated as a member of the Schoharie Formation of the Tristates Group. May be equivalent to the Saugerties Formation.
Fossils: Ostracods. Others? (Confused because there is a well known Helderberg Group fossil site with diverse fossils on Rickard Hill Road in Schoharie and it is sometimes difficult to tell which is being discussed)
Up to 40 meters of sometimes abundantly fossiliferous gray calceraeous Middle Silurian mudstone found in Northwestern New York and adjacent Ontario where it overlies the Irondequoit Limestone and is overlain by the Lockport Dolomite. The lower half is designated as the Lewiston Shale member. The upper half is sparsely fossiliferous BurleighHill Shale in the Niagara and sparsely fossiliferous Gates Dolomite further East toward Rochester.
Fossils: Diverse marine fossils in the lower parts-- noted for it's occasional well preserved trilobites
50 meters or more of Middle Ordovician sandstones, shales, and grainstones (coarse limestones) found in SouthWestern Quebec where they overlie Lower Ordovician Beekmantown age rocks of the Oxford formation and are overlain by Black River age rocks of the Shadow Lake/Pamelia formations. The upper -- grainstone containing -- beds are sometimes referred to as the Saint Martin formation. Some authors have defined a Hogsback Formation including uppermost parts of the Rockcliffe and lower parts of the Shadow Lake formation.
Fossils: Ichnofossils(burrows). Others?
An obsolete term for about 20 meters of fossiliferous Middle Ordovician limestones found at the top of the Black River Group(Selby Formation) and the bottom of the Trenton Group (Napanee Formation). It was used for rocks exposed West and South of the Adirondack Mountains in New York and Ontario.
Fossils: TBPL
A few meters of Middle Silurian dolomite with thin shale interbeds found in Western New York and adjacent Ontario. The Rockway is the basal member of the Irondequoit Limestone of the Clinton Group. It overlies various members of the Clinton Group or Medina Group.
Fossils: Often poorly preserved brachiopods, graptolites, corals, nautilids
Up to 170 meters of Lower and sometimes Middle Silurian shale, siltstone, sandstone and hemetite found in Tennesee, Georgia, Kentucky, Virginia, and Alabama. It overlies the Clinch Sandstone/Chickamauga Formation/Athens Shale and is overlain by the Chattanooga Shale.
Fossils: fossils in the hematite beds
An Upper Devonian marine shale and sandstone formation found in the upper Sonyea Group interval in Central New York where it is the middle of three members corresponding to the Cashaqua Formation further West. It is overlain by the Rye Point Member and overlies the Pulteney Member
Fossils: ichnofossils
Up to 300 meters of poorly exposed dark Middle Devonian shales found in Maryland, Pennsylvania, West Virginia and Virginia. It overlies the Monterey Sandstone and is overlain by the Jennings Formation. Basically, the Romney includes the entire Middle Devonian in the area where it is exposed and individual beds are sometimes identified as members using the name of the more NorthEastern formations such as the Marcellus Shale. In some areas, the name Romney is no longer in use, having been replaced by Needmore/Tioga/Marcellus/Mahantango nomenclature.
Fossils: Conodonts, other Middle Devonian fossils
Up to 130 meters of Upper Silurian limestone,dolomite,siltstone,shale found in Eastern New York where it overlies Upper Silurian Salina beds and underlies the Devonian Manlius and Coeymans formations.
Fossils: largely unfossiliferous shallow water deposits. brachiopods, bryozoa, corals in some beds
Upper Cambrian/Lower Ordovician Sandstones found in the subsurface of Kentucky, Ohio, West Virginia and Pennsylvania. Not clear that it is ever exposed on the surface. The overlies the Copper Ridge Dolomite and is overlain by Knox Dolomite. It may be laterally equivalent to the Knox Dolomite,Chepultepec Dolomite, and/or the Gatesburg Formation
Fossils: sparse -- conodonts
Up to 25 meters of Lower Ordovician sandstone or sandy dolomite found in coarse grained crinoidal marine limestone found in Arkansas,Missouri,and Illinois. It overlies the Gasconade Dolomite and is overlain by the Jefferson City Formation
Fossils: conodonts. A few gastropod molds.
15 to 20 meters of silty, largely unfossiliferous, greenish Upper Ordovician tidal flat mudstone found in Kentucky Southwest of Cincinnati. It overlies the Ashlock Formation and is overlain by the Preachersville Formation/Rowland formation. It is considered to be the lower member of the Drakes Formation. It is roughly equivalent to the Waynesville Formation to the North and East.
Fossils: Few or none
As much as 16 meters of grey shale sandwiched between two 2-6 meter sandstone beds. It consists of Upper Devonian beach sandstones with fossiliferous conglomerates found in the Canadaway Group in Western New York. The Rushford occupies the same stratiagraphic interval as the Westfield Shale also found in Western New York. The Rushford overlies the Caneadea Formation and is Overlain by the Machias Sandstone.
Fossils: Marine fossils in conglomerates in the sandstone beds, occasional ichnofossils
Roughly 40 meters of highly fossiliferous Middle Ordovician limestones divided into a number of members. The nomenclature of beds in the Upper Trenton Group is complex, overlapping, and confusing. The Rust formation is found the Southwest, west and North of the Adirondack mountains of New York and adjacent Ontario where it is known as the lower member of the Cobourg Formation. The Rust formation overlies the Denley formation and is overlain by the Steuben formation To the SouthEast, it thins and eventually transitions into black "Utica Shales".
Fossils: TBPL
An Upper Devonian marine shale formation found in the upper Sonyea Group interval in Central New York where it is the uppermost of three members corresponding to the Cashaqua Formation further West. It is overlain by the black shale beds of the Moreland Shale of the West Falls Group and overlies the Rock Stream Member.
Fossils: possibly
600 meters of shallow water marine Lower Ordovician carbonate deposits found in the Southern Arm area of SouthWest Newfoundland. It includes the Watts Bight, Boat Harbour, Catoche, and Aguathuna LimestoneFormations. It overlies the Port-au-Port Group and is overlain by the Table Head Group An alternative sequence is St. Barbace Point Dolomite,Catoche Limestone,Port-au-Choix Dolomite.
Fossils: Conodonts, diverse marine invertebrates in some beds.
Apparently the same as the Bonneterre Dolomite/Limestone.
The uppermost portion of the Middle Ordovician RockCliffe Formation formation found in Eastern Ontario.
Fossils: TBPL
Up to 70 meters of Middle Ordovician sandstone found in Arkansas,Missouri,Illinois,Indiana,Ohio,Minnesota,Wisconsin,Michigan,Nebraska,Oklahoma,South Dakota, and West Virginia It overlies the Everton Formation/Oneota Formation/Deadwood/Shakopee Formation/Yellville Formation and is overlain by the Rountree Formation/Horicon Formation/Platteville/Glenwood/Sylamore Sandstone/Boone Formation/Joachim limestone/Izard Limestone/Trenton age limestone. It is laterally equivalent to the Winnipeg Formation
Fossils: Ichnofossils
An Uppermost Devonian marine conglomerate of waterworn quartz pebbles and sand several meters thick found in the Cattaragus Formation and Venango Formation of Western New York. It has been suggested that the various conglomerates found at the same stratiagraphic level regionally represent river channel fills.
Fossils: unknown, but similar, possibly contemporaneous, conglomerates in the area (Pope Hollow, Panama, Wolf Creek], etc) contain brachiopods-Spirifera, Ptychopteria
65 meters of Middle Silurian dolomite found in in Indiana where it overlies the Brassfield Formation and is overlain by the Waldron Shale/Pleasant Mills Formation. It is equivalent to the Osgood Formation plus the Laurel Dolomite
Fossils: marine invertebrates
An interval of poorly exposed slightly fossiliferous Middle to Upper Silurian evaporites (gypsum, shale) as well as more normal sediments lying between shallow water deposits in Northern New York and adjacent Ontario. It includes the Vernon Shale, Syracuse Formation and Camillus Shale. It overlies the Lockport Group and is overlain by the uppermost Silurian beds in the region -- The Bertie Limestone, and Akron Dolomite.
Fossils: TBPL
up to 20 meters of fossiliferous Upper Ordovician sandy dolomitic limestone Southwest Ohio,Indiana,and Kentucky. The Saluda overlies the Liberty Formation/Drakes Formation/Tanners Creek. It is overlain by the Brassfield Limestone/Whitewater Formation. It is a member of the Richmond Group.
Fossils: Corals in the lower part.
Cherty Late Lower Devonian marine beds found in Eastern New York. Treated as the uppermost(?) member of the Schoharie Formation of the Tristates Group. Is equivalent to the Leeds Facies of the Schoharie Formation.
Fossils: Unknown
40 meters or so of Lower or Middle Silurian sandstone, mudstone and shale from the Clinton Group that interfingers into the Otsquago Sandtone in Central New York.
Fossils: TBPL
An Upper Devonian black marine shale found in the Sonyea Group in Central New York. It overlies gray mudstones of the Johns Creek Formation. Further West where the Johns Creek pinches out, the Sawmill Creek merges with the underlying Montour shale to form the black shale unit in the Middlesex Formation #Middlesex].
Fossils: Unknown
Up to 1400m of Upper Ordovician graywacke, shale, sandstone, siltstone found above the Utica Shales in the lower Mohawk River Valley and adjacent areas.
Fossils: TBPL
300m of Chemung age gray Upper Devonian marine shale and sandstone found in West Virginia, Virginia, Maryland and Pennsylvania. It is a member of the Greenland Gap Group. It overlies the Brallier Formation and is overlain by the Foreknobs Formation
Fossils: Present
30 meters or more of fossiliferous Late Lower Devonian Sandstone and Siltstone found in Eastern New York and adjacent Pennsylvania. It overlies the Lower Devonian Esopus Sandstone and is overlain by the Middle Devonian Onondaga Group Limestones. The Schoharie is sometimes divided into the Aquetuck,Carlisle Center,Rickard Hill, and Saugerties members.
Fossils: Said to be abundant in some beds.
25 meters of Upper Silurian dolomite found in a few exposures around Sconondoa, Oneida County, NY. Throught to be an Eastern equivalent of the Eramosa Dolomite of the Lockport Group
Fossils: Unknown
A thin fossiliferous, dark limestone sometimes found at the base of the Trenton Group overlying the Black River Group and overlain by the Napanee Limestone. It is found in isolated occurances in the Mohawk Valley of New York and more reliably to the West and Northwest of the Adirondacks in New York and Ontario. It may be present in the Champlain Valley of New York. Some authors include it in the Chaumont (Watertown) Formation, others in the Rockland, and yet others in the Trenton.
Fossils: TBPL
A regional name for the Middle Devonian Onondaga Limestone Group in the Monroe County area NorthEast Pennsylvania and possibly in adjacent New Jersey and New York. 22 or more meters of fossiliferous (?) Middle Devonian Limestone interbedded with shale overlying the Esopus Grit equivalents and overlain by the Marcellus Black Shale.
Fossils: Probably
Obsolete term for up to 6 meters of Middle Devonian limestone and calcaerous sandstone found in Indiana and Kentucky. It overlies the Jeffersonville Limestone and is overlain by the New Albany Shale It is equivalent to the North Vernon Limestone It is sometimes subdivided into Silver Creek and Beechwood members.
Fossils: brachiopods,bivalves,crinoid fragments
5-7 meters of fossiliferous dark shaly organic rich Middle Devonian limestone found in Central New York, Pennsylvania, and Ohio. It is a member of the Onondaga Group. It overlies massive Moorehouse formation limestones and is overlain by the black, organic rich Marcellus Shales Formation.
Fossils: Brachiopods, cephalopods. There is a bone bed at the base of the unit.
Up to 35 meters of Upper Ordovician red shales and limestones found in Georgia, Alabama, Tennessee and Virginia. It overlies the Fairview Formation/Chickamauga Limestone and underlies the Clinch Formation/Rockwood Formation. It is laterally equivalent to the upper Richmond Group to the Northwest,the Juniata Formation to the NorthEast, and the Fernvale Formation. It has been subdivided into the Ringgold Formation,Shellmound Formation, and Mannie Formation.
Fossils: ichnofossils only?
Up to 900 meters of calcaerous Middle Ordovician marine shales found in Virginia, Tennessee and Georgia. It overlies the Holston Marble/Chota Formation/Tellico Sandstone. It is overlain by the Bays formation. It is a member of the Blount Group.
Fossils: Present. Not clear how abundant they are.
Red and green Middle Ordovician shales, sandstones, dolostones of Black River age found in Eastern Ontario. The terminology has also been used for similar rocks in Pennsylvania. It is roughly equivalent to the Pamelia at the base of the Trenton Group. It overlies the Beekmantown age Rockcliffe Formation and is overlain by the Gull River Limestone
Fossils: TBPL
Up to 60 meters of brownish Upper Cambrian or Lower Ordovician dolomite found in Iowa, Minnesota, Illinois, Wisconsin and Michigan. It overlies the New Richmond Sandstone beds and is overlain by the St Peter Sandstone
Fossils: a few mollusks and others in cherty beds
Up to 150 meters of Lower and Middle Silurian sandstone and conglomerate found in SouthEast New York and adjacent New Jersey and Pennsylvannia. It grades west into Bloomsburg Beds. It overlies Clinton Age beds and is overlain by Salina age beds
Fossils: Eurypterids, Vernonaspis
An obsolete(?) name for Lockport Group Silurian beds in New York(?) and Ontario(?) now referred to as the Devils Hole Dolomite.
Fossils: Unknown
Fossiliferous Upper Devonian marine siltstones and shales found in East Central New York. It is a member of the Genesee Group. Sherburne beds overlie Middle Devonian Hamilton Group beds and are apparently overlain by the Ithaca Formation.]
Fossils: Reticularia
150m of fossiliferous Middle to Upper Ordovician marine sandstone found in Eastern Pennsylvania. It overlies the Dauphin Shale of the Martinsburg Shales. The relationship, if any, between the Shochary Sandstone and the Shochary Ridge Formation is unclear.
Fossils: Abundant and diverse -- brachiopods,trilobites,gastropods,bryozoa,bivalves,ostracods,crinoids.
100m of fossiliferous Upper Ordovician marine Martinsburg shale Exposed on Shochary Ridge in Lehigh County in Eastern Pennsylvania. It overlies the undifferentiated non-fossiliferous Martinsburg Shales. The relationship, if any, between the Shochary Sandstone and the Shochary Ridge Formation is unclear.
Fossils: Abundant and diverse -- brachiopods,trilobites,gastropods,bryozoa,bivalves,ostracods,crinoids.
Highly fossiliferous Middle Ordovician fine textured grainstone limestones interbedded with thin fossiliferous shale layers. It overlies the Kings Falls Limestone of the Trenton Group and is overlain by the Denley Formation of the Trenton Group. It is equivalent to the Sugar River and Glens Falls formations in the Champlain Valley and may possibly be used for the Sugar River interval in Ontario adjacent to the area of New York West of the Adirondacks.
Fossils: TBPL
Up to 30 meters of black Lower Devonian marine shale with minor limestone and beds of black chert nodules found in Maryland,Pennsylvania,New Jersey, and West Virginia. It overlies the Glenerie Formation/Becraft Limestones/Mandata Formation] and is overlain by the Ridgeley Sandstone. Most authors consider it to be the lower or middle member of the Oriskany Sandstone or Old Port Formation
Fossils: Basically None? Enough conodonts to date the formation.
Perhaps 10 meters of unfossiliferous(?) Upper Devonian gray marine siltstone found in Southwestern New York and adjacent Pennsylvania lying above the shalier Westfield Formation and below the NorthEast Shale. The Shumla is a member of the Canadaway Group.
Fossils: Conodonts?
17 meters of gray, highly fossiliferous, Middle Devonian clays found in NorthWest Ohio and adjacent Michigan and Ohio. The Silica overlies the Dundee Limestone and is overlain by the Ten Mile Creek Dolomite. It is a member of the Traverse Group.
Fossils: Abundant, diverse, invertebrates
Fossiliferous Middle Ordovician marine beds found in SouthEast Ontario. Corresponds to the Ottawa Group in Western Quebec and NorthEast Ontario and the Chazy-Black River-Trenton sequence in the US. Overlies Beekmantown age beds of the Rockcliffe Formation and includes the Shadow Lake,Gull River,Bobcaygeon,Verulaum and Lindsay formations. The Simcoe is overlain by Upper Ordovician shales of the Blue Mountain and Georgian Bay Formation. The Simcoe Group contains abundant, diverse Middle Ordovician faunas in the upper beds.
Fossils: TBPL
| Upper Ordovician Georgian Bay Formation Shale |
| Upper Ordovician Blue Mountain Formation Black Shale |
| ORDOVICIAN SIMCOE GROUP |
|---|
| SOUTHEASTERN ONTARIO |
| Middle Ordovician ++Lindsay Limestones and Black Shales |
| Middle Ordovician ++Verulam Limestone |
| Middle Ordovician ++Bobcaygeon Limestone |
| Middle Ordovician ++Gull River Limestone |
| Middle Ordovician +Shadow Lake |
| Middle Ordovician Rockcliffe Limestones and shales |
An obscure Upper Devoninan marine shale found above the Renwick Shale in Central NY. It is a member of the Middlesex Shale.
Fossils: Unknown
Black to grey fossiliferous Middle Devonian shales with a few thin limestones. It is a member of the Hamilton Group. It overlies black, organic rich Marcellus shales from which it is seperated by the Stafford Limestone. It is overlain by the Centerfield Limestone which is overlain by shales of the Ludlowville Formation. It is widely distributed in the Northern United States South of the Mohawk River and West of the Applachian Front.
Fossils: TBPL
460-640 meters of Middle or Upper Devonian shale,sandstone,and conglomerate found in SouthEastern New York West of the Hudson River where it overlies the Katsberg Formation.
Fossils: Marine fossils? diversity and abundance unknown
A Lower Ordovician sandy dolomite found in Arkansas,Missouri,and Illinois. It has some complex interrelationship with the similar Powell Dolomte and Black Rock Dolomite
Fossils: None? Primitive bryozoa?
150 meters of fossiliferous Sandstone and shale found in a complex set of exposures at Snake Hill on the East shore of Saratoga lake in New York. Neither the base nor upper contact are exposed. The term has also been used for some isolated outcrops in the -- for want of a better term "Hudson River Group" black shales of the Albany, NY area where similar fossils -- probably transported -- have been found. Resembles some Austin Glen beds except for the presence of abundant fossils.
Fossils: Brachiopods, graptolites, gastropods -- Diverse marine invertebrates including graptolites.
Purple fossiliferous Lower Silurian shales from the Clinton Group overlying Medina Group limestones and underlying Clinton group sandstones/limestone in Western and Central New York.
Fossils: TBPL
Gray Middle Devonian sandstone and sandy siltstone found in East Central New York where it overlies the Bridgewater member of the Marcellus Shale. It is overlain by the Pecksport formation It is a member of the Marcellus Formation
Fossils: Brachiopods-Spinocyrtina, gastropods, corals
Up to 25 meters of fossiliferous Upper Devonian shales and siltstones found throughout the Appalachian region South of the Mohawk River and Ontario Plain in NY. In Northern New York, it includes the Middlesex and Cashaqua Shales. Other formations identified with the Sonyea include the Enfield Formation,Glen Aubrey Formation,Johns Creek Shale,Kattel Formation,Montour Shale,Parrish Limestone Bed,Pulteney Shale,Rock Stream Siltstone,Rye Point Shale,Sawmill Creek Shale,Triangle Formation,Walton Formation, and West Danby Member. The Sonyea is sometimes referred to as the Portage Group. The Sonyea overlies the Upper Devonian Genesee Group and is overlain by Upper Devonian rocks of the Nunda Group.
Fossils: TBPL
| Upper Devonian Nunda Group | |||
| UPPER DEVONIAN SONYEA GROUP | |||
|---|---|---|---|
| WESTERN NEW YORK | CENTRAL NY | EAST CENTRAL NY | |
| ++Cashaqua Shale | Rye Point Shale | ||
| ++Cashaqua Shale | Enfield Shale | Rock Stream Siltstone | |
| ++Cashaqua Shale | Enfield Shale | Pulteney Shale | |
| ++Cashaqua Shale | Enfield Shale | Sawmill Creek Shale | |
| ++Cashaqua Shale | Enfield Shale | Johns Creek Shale | |
| ++Cashaqua Shale | Enfield Shale | Montour Shale | |
| ++Middlesex Shale | |||
| Upper Devonian Genesee Group Shales | |||
A somewhat obsolete term for up to 40 meters of fossiliferous, calcaerous Upper Ordovician Shale and limestone found in Southwest Ohio as well as adjacent Indiana and Kentucky. It overlies the Economy Shale. It is overlain by the McMicken Shale. In modern usage, it is in the middle part of the Latonia Formation. It is a member of the Cincinnati Group
Fossils: Very Abundant, well preserved, Upper Ordovician fossils - Bryozoa,Brachiopods
270 to 450 meters of Early Ordovician limestones and dolomites found in the Southern Arm area of SouthWest Newfoundland. It overlies the Brent Island Limestone and is overlain by the Table Head Group. It is a member of the St George Group
Fossils: Gastropods, Cephalopods, Brachiopods, Trilobites
Middle Devonian limestone found in East Central New York where it overlies Carlisle Center shales. It is a member of the Onondaga Group.
Fossils: Probably.
2 to 3 meters of fossiliferous Middle Devonian cherty sandstone found within the lower part of the Edgecliff Limestone of the Onondaga Formation in the area of Hagersville, ON. It overlies the Oriskany Sandstone or Silurian formations and overlain by the Middle Devonian Onondaga Limestone.
Fossils: Present and fairly abundant?
A widespread thin unit of fossiliferous limestone that separates the Marcellus and Skaneateles Shales] of the Middle Devonian Hamilton Group in Northern New York.
Fossils: TBPL
Over 100m(?) of sandstone and conglomerate with minor shale in the Catskill Region of New York dividing the non-marine Middle Devonian Katsberg Formation into upper and lower parts.
Fossils: plant fossils near the Cannonsville Dam
Roughly 23 meters of fossiliferous Middle Ordovician limestone and shale divided into a number of members. The nomenclature of beds in the Upper Trenton Group is complex, overlapping, and confusing. The Steuben formation is found the Southwest, west and North of the Adirondack mountains of New York and adjacent Ontario where it is known as the Uppermost member of the Cobourg Formation. The Steuben formation overlies the Rust formation. Presumably it is overlain by black "Utica Shales". A few papers link the Steuben to a "Hiller Formation". To the SouthEast, the Steuben thins and eventually transitions into black "Utica Shales".
Fossils: TBPL
Up to 300m of Middle Ordovician marine Martinsburg Shale,siltstone,and limestone found in Virginia and West Virginia. It overlies the Edinburg Formation and is overlain by the Martinsburg Shales.
Fossils: Conodonts. Macrofossils?
Up to 700 meters (usually much less) of fossiliferous Middle Ordovician limestone,dolostone and clay found in Mississippi, Alabama, Georgia, and Tennessee. It includes the Lebanon Limestones/Carters Limestone/Jewell Bluff/Pond Spring Formation, Murfreesboro Formation, Ridley Formation. It overlies the Knox Group. It is overlain by the Nashville Group. In some areas, it is considered to be a member of the Chickamauga (Super)Group.
Fossils: Some beds have abundant, diverse, marine invertebrates
25 meters or more of calcerous Middle Devonian shale found in the Marcellus Shale interval in the Northern Catskill region of East Central New York. It is equivalent to the Cherry Valley Limestone of the Marcellus Shale further West. It overlies the Union Springs member of the Marcellus Shale and is overlain by the Mount Marion Formation of the Marcellus Shale.
Fossils: some beds have marine invertebrates
A fairly thick Middle to Late Ordovician black shale interbedded with occasional thin limestones. It is found the the Champlain and Richilieu Valley of Vermont,New York and Quebec where it overlies the Cumberland Head Formation and is overlain by the similar/indistinguishable Iberville Formation. It is unfossiliferous except for beds near the base that have a moderately abundant, but not very diverse fauna of graptolites, a trilobite, and cephalopods.
Fossils: TBPL
223 meters of Cambrian dolostone and limestone reported from the vicinity of Philipsburg, QC. Thought to be the same age as the Cairnside Formation found further West. Very likely is part of a "taconic" slice pushed in from the East during the Avalonian orogeny, but could be autocthonous. Fossils limited to to conodonts?
Fossils: TBPL
Up to 27 meters of highly fossiliferous Middle Ordovician fine textured grainstone limestones interbedded with thin fossiliferous shale layers. It overlies the Kings Falls Limestone of the Trenton Group and is overlain by the Denley Formation of the Trenton Group. It is equivalent to the Shoreham and Glens Falls formations in the Champlain Valley.
Fossils: TBPL
Upper Devonian marine sediments found in NorthWestern Pennsylvania and adjaent New York. USGS ascribes the Sunfish to the Conneaut Group. The legend for the New York State Geologic Map suggests that the Sunfish Formation occupies much of the interval ascribed to the Canadaway, Conneaut, and Conewango Groups.
Fossils: Unknown
About 10 meters of Upper Ordovician shale and limestone found in Southwest Ohio, and adjacent Kentucky. The Sunset Formation is the lower member of the Arnheim Formation. It overlies the Grant Lake Limestone and is overlain by the Oregonia Formation. It is laterally equivalent to the Dillsboro.Ashlock and Bull Fork formations.
Fossils: Marine invertebrates are sparse.
A thick sequence of Upper Devonian and Mississippian marine and continental beds found in SouthEast New York and adjacent Pennsylvania. It includes the Brallier Shale, Catskill Formation, Fort Littleton Formation, Harrell Shale, Lock Haven Formation, Mount Pleasant Formation, New Milford Formation, Oswayo Formation, Rush Formation, and Trimmers Rock Sandstone.
Fossils: brachiopods, ichnofossils, in the lower marine beds. Plants in the upper beds
6 meters of very pure Lower(?) Devonian sandstone exposed in Northwest Ohio, adjacent Michigan and Ontario. The Sylvania overlies the Bass Islands Dolomite and is overlain by the Amherstburg Dolomite. Many authors include the Sylvania Sandstone in the overlying Amherstburg Dolomite. The Sylvania is sometimes considered to be a member of the Detroit River Group.
Fossils: None?
Interbedded Upper Silurian shales,dolomites,evaporites-salt and gypsum-found in Northern New York in the Ontario Plain. It is a member of the Salina Group. It overlies the Vernon shale and is overlain by the Camillus formation. Fossils are reported -- arthropods and brachiopods.
Fossils: TBPL
An obsolete term for 70 meters of fossiliferous Upper Ordovician limestone and calcaerous shale exposed in SouthEast Indiana. The beds have been assigned to the Dillsboro Formation or the lithologically indistiguishable Arnheim/Waynesville/Liberty sequence. It overlies the Mount Auburn Limestone/Dillsboro Formation and is overlain by the Whitewater formation.
Fossils: abundant and diverse marine invertebrates in some beds
Up to 1500 meters of Middle Ordovician marine sandstone and shale found in Georgia, Tennessee, and Virginia. It overlies the Athens Shale/Blockhouse Shale. It is overlain by the Sevier Shale/Chota. It has also been called the Chapman Ridge Formation.
Fossils: Unknown
Upper Cambrian and Lower Ordovician sandstones, sandy dolostones and dolostones found in extreme Northern New York, Southern Ontario and adjacent Quebec where it overlies the Potsdam Formation/Group and underlies the Beekmantown or younger rocks. It is the lowest unit in the Beekmantown Group. The term has also been used in extreme Western Vermont and Pennsylvannia for rocks overlying the Potsdam. The relationship between the Theresa and formations such as the Hoyt, Galway, Tribes Hill, and Little Falls in the Mohawk Valley Formations is hazy. Sometimes abundant fossils are reported from some beds in the Theresa. In the early 19th Century, the modern Theresa was referred to as Division A of the Calciferous Formation. The Theresa was also referred to as the 'Passage Beds'.
Fossils: TBPL
4 to 11 meters of grey quartzite found at the top of the Early Silurian Medina Group in the Niagara region of New York and Ontario. It overlies red sandstones with diverse interbeds of the Grimsby Sandstone and is overlain by various formations Maplewood Shale,Sodus Shale, Neahga Shale, Reynales Limestone, Bear Creek Shale at the base of the Clinton Group. Depending on the Author, may or may not include Cambria Shales as the top of formation.
Fossils: ichnofossils
A relatively thin sequence -- 15 meters or less -- of Upper Devonian greenish grey and brown-black shale with some thin beds of other materials found in Ohio, Kentucky, Tennessee? and West Virginia. The Three Lick overlies the Huron Black Shale and underlies the Cleveland Black Shale It grades laterally into the Chagrin Shale. It is widely used as a marker bed when drilling for hydrocarbons through the very thick Upper Devonian shales of the Ohio Shale
Fossils: locally conodonts, algae, plant fragments, inarticulate brachiopods, fish fragments.
A widespread unit of fossiliferous limestone that separates the Ludlowville and Moscow Shales of the Middle Devonian Hamilton Group in Northern New York. In Western New York, the unit grades into shales mixed with pyrite beds with a lateral extent of a few hundred meters.
Fossils: marine invertebrates -- often reduced in size. Plant material.
Upper Cambrian(?) sandy dolomites exposed around Fort Ticonderoga in New York and nearby Fort Independence in Vermont. Since neither the upper or lower contacts are exposed, it is unclear exactly how the Ticonderoga relates to other Cambrian and Lower Ordovician beds in the area.
Fossils: TBPL
An Upper Devonian marine Sandstone equivalent to the Chemung Formation of Pennsylvania (and New York?) Overlain by the Sunfish Formation
Fossils: TBPL
Fossiliferous, Middle Devonian limestones and shales in NorthWest Indiana, Michigan and Ohio. The Traverse Group overlies the Dundee Limestone/Detroit River Group. It is overlain by the Squaw Bay Limestone/Antrim Shale. It includes a number of formations: Alpena Limestone, Beebe School Formation, Bell Shale, Charlevoix Limestone, Ferron Point Formation, Four Mile Dam Formation, Genshaw Formation, Gravel Point Formation, Jordan River Formation, Koehler Limestone, Newton Creek Limestone, Norway Point Formation, Petoskey Limestone, Potter Farm Formation, Rockport Quarry Limestone, Silica Formation, Tenmile Creek Dolomite, Thunder Bay Limestone.
Fossils: invertebrates-often abundant and diverse
Highly fossiliferous Middle Ordovician limestones found above the Black River limestones and below black Utica Shales in most states East of the Mississippi. In the Champlain Valley it consists of a lower Shoreham formation and an overlying Glens Falls formation and outcrops occasionally from Glens Falls north to Quebec. In the Adirondack region of New York it is subdivided into five formations. From oldest to youngest -- Napanee, Kings Falls, Sugar River, Denley, and Hiller. It is exposed in an arc from the Mohawk Valley, West of the Adirondacks, and North into Ontario. It is now thought that the overlying black "Utica" shale formations in some regions may be contemporateous with the Trenton limestones in other regions.
Fossils: Abundant, diverse marine fossils - brachiopods, cephalopods, trilobites
| Upper Ordovician Lorraine Group | |
| ORDOVICIAN TRENTON GROUP | |
|---|---|
| NY EAST of LAKE ONTARIO-ADJACENT ONTARIO | CHAMPLAIN VALLEY |
| Middle Ordovician ++Utica Shales | +Snake Hill Shale-+Stony Point Shale-+Cumberland Head-Iberville Shale |
| Middle Ordovician ++Hiller Limestone | |
| Middle Ordovician ++Denley Limestone-++Dolgeville | |
| Middle Ordovician ++Sugar River Limestone-++Dolgeville | ++Glens Falls Limestone |
| Middle Ordovician ++Kings Falls Limestone-++Larrabee limestone | |
| Middle Ordovician ++Napanee Limestone | ++Orwell limestone-IslelaMotte limestone |
| Middle Ordovician Black River Group | |
Upper Devonian Lower Ordovician shallow water marine mudstones found in East Central New York where they occupy the interval in the Sonyea Group between the Montour BlackShale below and the Sawmill Creek Black Shale. The unit thins westward and eventually grades into marine gray shales of the Johns Creek. On the East, the equivalent formation is the non-marine redbed sandstone of the Walton Formation
Fossils: plants, marine invertebrates
Lower Ordovician limestones exposed in the Mohawk Valley of New York and Eastward apparently as far as and possibly into the Taconic slices of Eastern New York. Overlies the Gailor Formation in some places. Is subdivided into the Fort Johnson, Palatine Bridge, Wolf Hollow, Fonda, Chuctanunda Creek and Cranesville members although some refer to some of the members as formations.
Fossils: TBPL
Up to 1220 meters of Upper Devonian marine siltstone, sandstone and shale found in central Pennsylvania with minor black shale Harrell Shale near base. It overlies the Tully Limestone and is overlain by the Catskill Formation. The Trimmers Rock formation is in part equivalent to the Ithaca Formation in New York and the Brallier Formation in the mid-Atlantic states.
Fossils: Marine fossils are present in some beds - brachiopods, crinoids, ichnofossils
Lower Devonian shales, sandstones, and limestones found in the area where New York, New Jersey and Pennsylvannia meet. It overlies Esopus Formation shales and is overlain by Middle Devonian Onondaga Limestones. Formations ascribed to the Tristates Group include the Bois Blanc Limestone, Carlisle Center Formation (or Shale), Connelly Conglomerate, Esopus Shale, Glenerie Formation, Oriskany Sandstone, Port Jervis Limestone, Rickard Hill Formation, Saugerties Formation, Schoharie Formation, Springvale Sandstone
Fossils: TBPL
| Middle Devonian Onondaga Limestone of the Hamilton Group | |||
| LOWER DEVONIAN TRISTATES GROUP | |||
|---|---|---|---|
| WESTERN NEW YORK | CENTRAL NY | CATSKILLS | |
| Bois Blanc Limestone | Rickard Hill Limestone | Schoharie Limestone | |
| Carlisle Center Shale | |||
| Esopus Shale | |||
| Oriskany Sandstone | Oriskany Sandstone | Glenerie Limestone | |
| Port Jervis Limestone | |||
| Lower Devonian Helderberg Group Limestones | |||
Probably in excess of 10 meters of fossiliferous Middle Devonian limestones belonging to the Hamilton Group. The Tully limestone separates the underlying Moscow Shale from the overlying Upper Devonian Genesee Group. Tully outcrops are found across Northern New York from the Finger Lakes region to near Lake Erie. In the Western part of the region the limestone is replaced by pyrite rich, fossiliferous beds.
Fossils: TBPL
An Uppermost Devonian marine conglomerate of waterworn quartz pebbles and sand several meters thick found in the Cattaragus Formation and Venango Formation of Western New York. It has been suggested that the various conglomerates found at the same stratiagraphic level regionally represent river channel fills.
Fossils: unknown, but similar, possibly contemporaneous, conglomerates in the area (Pope Hollow, Panama, Wolf Creek], etc) contain brachiopods-Spirifera, Ptychopteria
150 meters of Lower Silurian quartzite and sandstone found in Pennsylvania, Maryland, Virginia, and West Virginia where it overlies the Juniata Formation and is overlain by the Cacapon Sandstone.
Fossils: A few ichnofossils
About 30 meters of Upper Silurian shales and limestones found in Ohio and adjacent Michigan and Ontario. They overlie the Salina Group and are overlain by the Greenfield Dolomite. They are a member of the Bass Islands Dolomite Group
Fossils: abundant ostracods and stromatoporids, occasional brachiopods, molluscs,eurypterids
Five of so meters of black shale and Limestone Lower Marcellus Shale interval in the Northern Catskill region of East Central New York. It overlies the Onondaga Limestone and is overlain by the Cherry Valley Limestone/Berne Shale of the Marcellus Shale.
Fossils: some marine invertebrates in some areas - Paracardium,Buchiola
In nineteenth century usage, the Utica Shales tended to be any dark marine shales rich in organic matter found directly above Middle Ordovician Trenton age limestone in New York, Pennsylvania, Vermont, Quebec, Ontario, Ohio, Michigan, and Indiana. This includes the Canajoharie, Frankfort, Stony Point,, Iberville, Collingswood], and Gloucester formations. In general, the beds just above the Trenton are fossiliferous with a fauna that becomes limited to as one moves upward and eventually disappears. The formation is thickest in the East. In modern usage in the US, the term Utica seems to be restricted to up to 300 meters of gray to black petroliferous Middle Ordovician shales that replace the upper Trenton beds as one moves SouthEast from West Canada Creek in the Mohawk Valley of New York. The modern Utica Shale is subdivided into two members -- Flat Creek and Indian Castle separated in the Western part of the area by the Dolgeville limestone. The Flat Creek member is roughly equivalent to the Canajoharie Shale of older publications. In Quebec and Ontario, the usage is more like nineteenth Century usage.
Fossils: TBPL
Fossiliferous early Middle Ordovician limestones found in the Champlain Valley of New York and Vermont. It is the Upper member of the Chazy Limetone. It overlies the Crown Point member of the Chazy Group. It is overlain by limestones of the Black River Group
Fossils: The unit is fossiliferous, but the fossils are not especially common and are difficult to extract from the massive limestones.
Same as the Cattaragus formation. Submembers listed as Panama Conglomerate Member, Bimber Run Conglomerate Member, North Warren Shale Member, Pope Hollow Conglomerate Member, and Woodcock Sandstone Member.
Fossils: TBPL
Up to 130 meters of varied Upper Silurian shales and thin dolomites found in North Central New York where it overlies the Pittsford Shale and is overlain by the Syracuse Salt. It is a member of the Salina Group.
Fossils: Eurypterids,fish,bivalves,brachiopods
Richly fossiliferous Middle Ordovician limestones found in Eastern Ontario and Northwest Quebec. Corresponds to the middle part of the Trenton Limestones in the US. It overlies the Black River/Trenton age Bobcaygeon Formation and is overlain by the Trenton Age Lindsay Formation.
Fossils: Abundant and diverse marine invertebrates
Up to 4 meters of Middle Silurian clay, shale and a few thin limestones found in Indiana(se), Kentucky(cw), and Tennessee(cw). It overlies the Laurel Dolomite/Salamonie Dolomite and is overlain by the Louisville Limestone/Geneva Limestone
Fossils: Not always present, but in some exposures has abundant, diverse marine invertebrates -- brachiopods, complete trilobites, etc.
| 78m | Pennsylvanian,Middle | shale,sandstone | WV | Lower War Eagle Coal | Middle War Eagle Shale | fossils:Marine invertebrates | GEOLEX link | NO cgkn link | Kanawha |
|---|
Up to 50 meters of Lower and Middle Silurian shales and limestones found in Mississippi,Alabama,and Tennessee. It overlies the Brassfield Limestone/Patterson Sandstone and is overlain by the Chattanooga Shale/Brownsport Formation. The unit includes a number of Middle Silurian formations - the Osgood limestone, Laurel limestone, Maddox Formation, Waldron clay, Lego limestone, and Dixon limestone.
Fossils: Marine invertebrates
Five or six meters of Lower Silurian dolomitic marine limestone found in parts of Western New York East of Rochester. It overlies the Reynales Limestone and is separated from it by the Furnaceville Hematite. It is overlain by the Sodus Shale. Often treated as a member of the Reynales Limestone
To the West, the Wallington becomes shalier eventually transitioning into the Bear Creek Shale
Fossils: Probably
28 meters of Upper Silurian heterogenous marine beds found in Northwest New Jersey and adjacent Pennsylvania where it overlies the Bossardville Limestone and underlies the Rondout Formation. It is a member of the Decker (Decker Ferry) formation and is laterally equivalent to the more-calcaerous Clove Brook Limestone to its NorthEast.
Fossils: Ichnofossils, invertebrates (?)
Upper Devonian fluvial siltstones,conglomerate,and sandstones found in SouthEastern New York. It is roughly equivalent in age to the marine Sonyea formation further west.
Fossils: TBPL
As much as 45 meters of fossiliferous Middle Ordovician Black River age coarse grained limestone found in Virginia and West Virginia where it overlies the Lincolnshire Limestone and is overlain by the Peery Limestone
Fossils: TBPL
Roughly 66 meters of fossiliferous Black River age Middle Ordovician limestone and shale found in Tennessee, Virginia, and West Virginia. It overlies the Benbolt Limestone or the Gratton Formation and is overlain by the Bowen Formation mudstones.
Fossils: TBPL
About 100 meters of Lower Ordovician limestone and dolomite found in the Southwest Arm area of Newfoundland. It overlies the Port-au-port Group and is overlain by the Boat Harbor Formation. It is the lowermost member of the St George Group
Fossils: conodonts. trilobites, other marine invertebrates
Roughly 30 meters of fossilifrous greenish Upper Silurian dolomitic limestone and shale found in Ulster County, NY and adjacent Pennsylvannia. Where present, it overlies the Shawangunk Conglomerate and is overlain by the High Falls shale.
Fossils: Abundant marine invertebrates in basal limestones?
Middle Ordovician grey limestones found above the Lowville formation in Northern New York and Ontario on and East of Lake Ontario. Depending on the author it is the youngest formation in the Black River Group or the oldest in the Trenton. It is equivalent to the Chaumont formation.
Fossils: TBPL
up to 17 meters of fossiliferous Upper Ordovician clay and limestone found in Southwest Ohio, Indiana, and Kentucky. The Waynesville overlies the Arnheim Formation. It is overlain by the Liberty Formation. It is a member of the Richmond Group and is sometimes subdivided into Blanchester, Clarksville, and Fort Ancient members. It has been included by at least one author in a Tanners Creek Formation along with the lithologically similar Arnheim and Liberty formations
Fossils: Marine invertebrates are common, well preserved, and abundant.
Interbedded grey marine Upper Devonian shales and sandstones found in Western New York. The Wellsville is a member of the Conneaut Group. The Wellsville overlies similar beds in the Canadaway Group and is overlain by Dexterville or Cattaragus shales.
Fossils: a few ichnofossils, some shell coquinas
Upper Devonian marine sediments of the Sonyea Group in North Central New York that occupy the entire Upper Sonyea interval. It presumably overlies the Sawmill Creek Black Shale and underlies the Moreland Black Shale/Rhinestreet Black Shale.
Fossils: Probably marine invertebrates
Thick Upper Ordovician marine Martinsburg calcaerous sandstone and shale found in South Central Pennsylvania and adjacent New Jersey.
Fossils: Unknown
Sparsely fossiliferous, marine, Upper Devonian shales and limey shales found in Western New York and adjacent areas. Where best known in Western New York, it is subdivided into a lower black Rhinestreet Shale and an upper gray mudstone -- Angola Shale with limestone nodules -- the Rhinestreet Formation. Many other formations/members: Angola Shale,Nunda Sandstone,West Hill,Gardeau Shale,Grimes Siltstone,Hatch Shale,Rhinestreet Shale,Walton Formation,Moreland Shale,Millport Shale,Beers Hill Formation,Slide Mountain Formation, and Honesdale Formation. The West Falls beds overlie the Sonyea Group and are overlain by the Canadaway Group.
Fossils: TBPL
| Upper Devonian Canadaway Group | ||||
| UPPER DEVONIAN WEST FALLS GROUP | ||||
| WESTERN NEW YORK | CENTRAL NY | |||
| Hanover Shale | Wiscoy Shale/Sandstone | Chemung Shale/Sandstone | Slide Mountain Shale/Sandstone | Lackawaxen Shale/Sandstone |
| [Angola Shale | Nunda Shale/Sandstone | Chemung Shale/Sandstone | Slide Mountain Shale/Sandstone | Lackawaxen Shale/Sandstone |
| Rhinestreet Shale | Chemung Shale/Sandstone | Slide Mountain Shale/Sandstone | Lackawaxen Shale/Sandstone | |
| Upper Devonian Sonyea Group Shales | ||||
Perhaps 50 meters of possibly fossiliferous Upper Devonian gray marine shales found in Southwestern New York lying above the siltier Laona Formation and below the Shumla Siltstone. The Westfield is a member of the Canadaway Group. There is no GEOLEX entry for the Westfield.
Fossils: Unclear, Ammonites have been found in beds that might be as young as the Laona or Westfield.
Hematitic Lower Silurian Clinton Group Limestone found in North Central New York it overlies the Sauquoit Shale and is overlain by the Willowvale Shale.
Fossils: Unknown. Other Silurian hematites commonly contain microfossils, some dwarfed macrofossils. and fragments of macrofossils such as bryozoa.
Upper Devonian shales of the West Falls Group found in central New York and Pennsylvania. It overlies the Gardeau Formation? and is overlain by the Nunda Formation.
Fossils: Brachiopods, ophuioids, others?
Upper Devonian black marine shales with concretions found in Central New York and throughout the NorthEast. It occupies the interval above the Geneseo Shale and below the Middlesex Shale It is member of the Upper Devonian Genesee Group. It overlies the Genundewa Limestone and is overlain by heavy black Middlesex Shales
Fossils: moderately abundant, but not very diverse -- Bactrites,Buchiola,Pleurotomaria,Lingula,Pterochaenia,Orbiculoidea
A Lower Ordovician limestone/sandy limestone/marble found in West Central Vermont. It is laterally equivalent to the Bridport Dolomite further West. It overlies the Burchards Formation. It is assigned by various authors to the Chipman Formation and the Providence Island Formation
Fossils: sparse due to alteration of the rock
70 meters of fossiliferous mid to upper Ordovician siltstone,shale,and sandstone underlying the Oswego Sandstone in areas along the South shore of Lake Ontario
Fossils: TBPL
Up to 9 meters of Early Silurian Medina Group sandstone that overlies the Ordovician Queenston Shale and is overlain by the Jolley Cut Formation. It is found in the Niagara region of New York and Ontario. In older usage, it may be included as a member of the Albion Group
Fossils: Phosphatic fossil fragments.
Fossiliferous mid-upper Ordovician oil shales found in Southern Ontario overlain by Upper Ordovician Georgian Bay shales and limestones.
An Upper Cambrian-Lower Ordovician dolomite exposed at Whitehall, NY. Unclear whether it is a continental platform formation or a part of a Taconic slice
Fossils: TBPL
Interbedded grey marine Upper Devonian shales and sandstones found in Western New York. The Wellsville is a member of the Conneaut Group. The Wellsville overlies similar beds in the Canadaway Group and is overlain by Cattaragus shales. It is distinguished from the similar age Wellsville Formation by the greater proportion of sand in its components
Fossils: a few ichnofossils, some shell coquinas
up to 15 meters of fossiliferous Upper Ordovician shale and limestone found in Southwest Ohio, and Indiana. The Liberty overlies the Liberty Formation. It is overlain by the Drakes Formation/Saluda Formation. It is a member of the Richmond Group.
Fossils: Marine invertebrates are common, well preserved, and abundant.
An Upper Silurian member of the Rondout Formation with a distinctive coral fauna. It overlies the Binnewater Sandstone and underlies heterogenious strata of the Rondout Formation.
Fossils: Ptenophyllid corals
Up to 25 meters of fossiliferous Lower Silurian Clinton Group black shales above a phosphatic bed found in Northern New York. It is laterally equivalent the Willowvale shale in the Mohawk Valley.
Fossils: TBPL
Fossiliferous Lower Silurian Clinton Group shales above a phosphatic bed found in the Mohawk Valley of New York. It is laterally equivalent the Williamson shales exposed further West in Northern New York.
Fossils: TBPL
5 meters or more of somewhat fossiliferous gray Middle Devonian Hamilton Group beds found in areas of New York where the Tichenor Pyrite/Limestone is not present and the younger Moscow Shale can not easily be distinguished from the underlying Ludlowville Shale. The Windom Shale overlies the Kashong Shale and is generally capped by thin limestones that mark the top of the Hamilton Group.
Fossils: Fairly abundant, well preserved and diverse Middle Devonian marine fossils.
Same as Coalburg Coal
| 30m | Pennsylvanian,Middle | shale,sandstone,coal,limestone | WV(sw) | Dingess shale | War Eagle Sandstone | Breathitt | fossils:marine invertebrates,plants | [GEOLEX link | NO cgkn link | Kahawha |
|---|
Fossiliferous grayish purple Devonian marine calcaerous shales and siltstones found in Western New York . In New York, it is the uppermost member of the West Falls Group. It overlies the black marine shale of the Pipe Creek Shale and is overlain by the marine shales and sandstones of the Caneadea Formation of the Canadaway Group. To the West, it grades into the less silty Hanover Shale
Fossils: Ichnofossils, wood fragments
400 meters or more of non-marine Upper Devonian gray-whie quartz pebble conglomerate with red sandstone interbeds found in East Central New York above the Hamilton interval. It overlies the Stony Clove Sandstone Formationand is overlain by the Slide Mountain Conglomerate. It is considered to be a member of the Katsberg Formation
Fossils: None?
Roughly 33 meters of fossiliferous Black River age Middle Ordovician limestone found in Tennessee, Virginia, and West Virginia. It overlies the Gratton Limestone ]and is overlain by the Moccasin Formation
Fossils: TBPL
An Uppermost Devonian marine conglomerate of waterworn quartz pebbles and sand several meters thick found in the Cattaragus Formation and Venango Formation of Western New York. It has been suggested that the various conglomerates found at the same stratiagraphic level regionally represent river channel fills.
Fossils: brachiopods,cephalopods,echinoderms-crinoids,bivalves-Modiola,Modiomorpha[?],Ptychopteria Similar, possibly contemporaneous, conglomerates in the area (Pope Hollow, Panama, Tunangwant], etc) contain brachiopods-Spirifera, Ptychopteria
Marine Lower Ordovician dolomites and dolomitic limestone exposed occasionally in New York's Mohawk Valley. The Wolf Hollow is a member of the Tribes Hill Formation. It overlies dolomites and shales of the Palatine Bridge Member and is overlain by dolomitic limestones of the Fonda member. The term Wolf Hollow is also used for younger beds within the Trenton Group to the North and West of the Lower Ordovician beds of the Tribes Hill Formation
Fossils: Cephalopods,Gastropods
Upper Devonian marine sandstones of the Venango Formation of the Conewango Group found NorthWest Pennsylvania where they overlie the North Warren Shale and are overlain by the Riceville Shale
Fossils: Unknown. Probably Present. Possibly abundant
About 90 meters of Middle Ordovician limestones found in Virginia and Tennessee. It overlies the Hurricane Bridge Limestone and is overlain by the Ben Hur Limestone It is a member of the Chickamauga Group
Fossils: Stromatoporoids, others?
New York
Generalized Bedrock Geology of NY
Vermont
State map http://dec.vermont.gov/geological-survey/publication-gis/VTrock
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