Geologic units in Cattaraugus county, New York

Conneaut Group, undivided (Upper Devonian) at surface, covers 53 % of this area

In west: Ellicott and Dexterville Formations-shale, siltstone. In east: Germania Formation-shale, sandstone; Whitesville Formation-shale, sandstone; Hinsdale Sandstone; Wellsville Formation-shale, sandstone; Cuba Sandstone.

Machias Formation (Upper Devonian) at surface, covers 24 % of this area

Shale, siltstone; Rushford Sandstone; Caneadea, Canisteo, and Hume Shales; Canaseraga Sandstone; South Wales and Dunkirk Shales.

Oswayo and Venango Formations (Upper Devonian) at surface, covers 16 % of this area

Shale, siltstone, sandstone; replaced eastwardly by Cattaraugus Formation-shale, sandstone, conglomerate.

Northeast Shale and Shumla Siltstone (Upper Devonian) at surface, covers 5 % of this area

Northeast Shale and Shumla Siltstone.

Gowanda, South Wales, and Dunkirk Shales (Upper Devonian) at surface, covers 0.7 % of this area

Gowanda, South Wales, and Dunkirk Shales.

Westfield Shale and Laona Siltstone (Upper Devonian) at surface, covers 0.3 % of this area

Westfield Shale and Laona Siltstone.

Cuyahoga and Knapp Formations (Lower Mississippian) at surface, covers 0.3 % of this area

Cuyahoga Formation - shale, sandstone; Corry Sandstone; Knapp Formation - shale, conglomerate 60-100 ft. (20-30 m).

Connoquenessing and Sharon Formations (Lower Pennsylvanian) at surface, covers 0.1 % of this area

Sandstone, shale; Sharon Formation-shale, sandstone, conglomerate; Olean Conglomerate 50-100 ft. (15-30 m).

Chadakoin Formation (Devonian) at surface, covers < 0.1 % of this area

Light-gray or brownish siltstone and some sandstone, interbedded with medium-gray shale; included in Conneaut Group and "Chemung" of earlier workers; marine fossils common; includes "pink rock" of drillers.

Wiscoy Formation (Upper Devonian) at surface, covers < 0.1 % of this area

Sandstone, shale; Hanover and Pipe Creek Shales.

Shenango Formation through Oswayo Formation, undivided (Mississippian and Devonian) at surface, covers < 0.1 % of this area

Greenish-gray, olive, and buff sandstone and siltstone, and gray shale in varying proportions; includes "Pocono" ("Knapp") and Oswayo of earlier workers; difficult lithologic distinction between Oswayo and "Knapp"- "Pocono" south and east of type area at Olean, N. Y.; contains marine fossils; includes lateral equivalents of Shenango Formation, Cuyahoga Group, Corry Sandstone, Bedford Shale, and Cussewago Sandstone, plus Oswayo Formation.

Catskill Formation (Devonian) at surface, covers < 0.1 % of this area

Grayish-red sandstone, siltstone, shale, and mudstone; units of gray sandstone occur in upper part; lithologies in upper part arranged in fining-upward cycles. In the Altoona area, the Catskill Formation is mapped as the Duncannon, Sherman Creek, and Irish Valley Members, which are described under "Central and Eastern Pennsylvania" provinces.

Venango Formation (Devonian) at surface, covers < 0.1 % of this area

Light-gray siltstone interbedded with some flaggy, gray sandstone and some bluish-gray shale; Panama Conglomerate and Woodcock Sandstone are, respectively, the lower and upper key beds defining the formation; referred to as "Cattaraugus" by some workers; includes some red shales where it interfingers to the east and south with the Catskill Formation; marine fossils present.

Shenango Formation through Riceville Formation, undivided (Mississippian and Devonian) at surface, covers < 0.1 % of this area

Sandstone, siltstone, and shale in varying proportions; distinguished from Shenango-through-Oswayo (MDso) interval on basis of more common gray shale in Riceville as compared with olive-colored shale and sandstone of Oswayo; contains marine fossils.

Pottsville Formation (Pennsylvanian) at surface, covers < 0.1 % of this area

Predominantly gray sandstone and conglomerate; also contains thin beds of shale, claystone, limestone, and coal; includes Olean and Sharon conglomerates of northwestern Pennsylvania; thin marine limestones present in Beaver, Lawrence, and Mercer Counties; minable coals and commercially valuable high-alumina clays present locally.