Trenton Group and Black River Group, undivided (WVOtbr;0)

Trenton Group and Black River Group, undivided

Trenton Group: dark, crystalline, nodular, and argillaceous limestones, with some metabentonite streaks. Includes the Nealmont, Oranda, Edinburg, and the upper part of the Chambersburg Limestones of northeastern West Virginia; also the Moccasin and Eggleston Formation of Mercer and Monroe Counties. Black River Group: predominantly gray aphanitic limestones, with many bioclastic streaks; siliceous in the lower part.

State	West Virginia
Name	Trenton Group and Black River Group, undivided
Geologic age	Ordovician
Lithologic constituents	Major Sedimentary > Carbonate > LimestoneTrenton Group: dark, crystalline, nodular, and argillaceous limestones. Black River Group: predominantly gray aphanitic limestones, with many bioclastic streaks; siliceous in the lower part. Incidental Sedimentary > Clastic > Mudstone > Claystone > BentoniteTrenton Group: with some metabentonite streaks
Comments	Printed map has no indiviual description for this unit and no name, but has individual symbol and color. Only uses brackets to combine Ot and Obr. Otbr is used in digital map, so combined Ot and Obr together and called this the "Trenton Group and Black River Group, undivided". Combined thickness: Northeastern 470-1010 ft, Western 890 ft, Southeastern 665 ft.
References	Cardwell, D.H., Erwin, R.B., and Woodward, H.P., 1968 (slightly revised 1986), Geologic Map of West Virginia: West Virginia Geological and Economic Survey, Map 1, East Sheet, scale 1:250,000.
NGMDB product	NGMDB product page for 13205
Counties	Berkeley - Jefferson - Mercer - Monroe

Trenton Group and Black River Group, undivided

Cardwell, D.H., Erwin, R.B., and Woodward, H.P., 1968 (slightly revised 1986), Geologic Map of West Virginia: West Virginia Geological and Economic Survey, Map 1, East Sheet, scale 1:250,000.