USGS Home
Contact USGS
Search USGS

Mineral Resources > Online Spatial Data > Geology > by state > New York Geology

Geologic units in Allegany county, New York

Nunda Formation (Upper Devonian) at surface, covers 0.3 % of this area

Nunda Formation - sandstone, shale.

Lithology: sandstone; shale

Machias Formation (Upper Devonian) at surface, covers 48 % of this area

Machias Formation - shale, siltstone; Rushford Sandstone; Caneadea, Canisteo, and Hume Shales; Canaseraga Sandstone; South Wales and Dunkirk Shales.

Lithology: shale; siltstone; sandstone

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

Chadakoin Formation - 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.

Lithology: siltstone; shale; sandstone

Oswayo and Venango Formations (Upper Devonian) at surface, covers 10 % of this area

Oswayo and Venango Formations - shale, siltstone, sandstone; replaced eastwardly by Cattaraugus Formation-shale, sandstone, conglomerate.

Lithology: shale; siltstone; sandstone; conglomerate

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

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

Lithology: sandstone; shale; conglomerate

Conneaut Group, undivided (Upper Devonian) at surface, covers 41 % of this area

Conneaut Group, undivided - 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.

Lithology: shale; sandstone; siltstone

Wiscoy Formation (Upper Devonian) at surface, covers 1 % of this area

Wiscoy Formation - sandstone, shale; Hanover and Pipe Creek Shales.

Lithology: sandstone; black shale; shale

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

Catskill Formation - Grayish-red sandstone, siltstone, shale, and mudstone; locally conglomeratic; contains gray sandstone in upper part; lithologies arranged in fining-upward cycles; equivalent to the Hampshire Formation south of Pennsylvania.

Lithology: sandstone; siltstone; shale; mudstone; conglomerate