FACIES ANALYSIS AND DEPOSITIONAL ENVIRONMENT OF THE AMES MARINE MEMBER (VIRGILIAN) OF THE CONEMAUGH GROUP (PENNSYLVANIAN) IN THE APPALACHIAN BASIN (KENTUCKY, MARYLAND, OHIO, PENNSYLVANIA, WEST VIRGINIA, COAL, QUARTZ, GLAUCONITE)

The lithologic and paleontological aspects for fifty localities of the Ames Marine Member (Virgilian) of the Glenshaw Formation, Conemaugh Group (Pennsylvanian) in the Appalachian basin were examined. The regional stratigraphic reconstruction shows that it is variably composed of limestone and shale, and often associated with a thin basal coal seam. A generalized, composite stratigraphic section of the Ames Member consists of the following units from top to bottom: The Grafton Sandstone, Nonmarine Shale, Upper Ames Shale, Upper Ames Limestone, Middle Ames Shale, Lower Ames Limestone, Lower Ames Shale, Ames Coal, Nonmarine Silty Shale, and Harlem Coal. Harlem Coal is commonly the basal coal in Ohio, and the Ames Coal is common in Pennsylvania and West Virginia.;The areal and vertical distribution of the different facies reflects the transgression-regression history of the Ames Cycle. A uniform, slow eustatic rise of sea level with an early rapid transgression was responsible for the deposition of most of the Ames marine section. The small, upper, underdeveloped regressive section suggests a rapid regression by active prograding deltaic deposits which rapidly terminated the marine conditions over most of the Appalachian Basin.;Insoluble residue analysis of 223 samples shows that quartz and glauconite are the major and significant residues. Both of them are common in areas fairly distant from the paleoshoreline. The major petrographic components of the Ames rocks are bioclastic grains of echinoderm, brachiopods, molluscs, bryozoa, and foraminifera in a matrix variably composed of clay and calcium carbonate. A quantitative microfacies study applying factor and cluster analysis reveals five basin-wide biofacies and four lithofacies reflecting a gradient from shoreline to an offshore position. The biofacies are: Molluscan; a molluscan-dominated facies representing semi-isolated interdeltaic bays or estuaries, Neochonetes; Neochonetes brachiopod dominated represent an open circulation, nearshore environment, Crurithyris; Crurithyris brachiopod-dominated facies representing a high energy, tidal wave-dominated environment, Echinoderm-Bryozoa; an offshore, subtidal environment, and Fusulinids; characterized by the occurrence of Fusulinids, and represents an offshore, open marine environment. The lithofacies are: Limestone; normal marine environment, Sandy Limestone; an intermix of normal marine carbonate and deltaic sand, Nodular Shale; an intermediate lithofacies between limestone and shale, and Shale; a prodeltaic sediment.