On the 'Snake Hill Shale'

Abstract

Restudy of the terrain mapped as "Snake Hill Shale" in eastern New York reveals that at least 3 lithic units are present in it. One of these underlies the other 2, which are lateral equivalents of each other. At Snake Hill, the type locality of the "Snake Hill Shale," the upper part of the Normanskill Formation is the only unit present and the Austin Glen Graywacke member forms the crest of the hill. A lithic unit composed of pebbles, cobbles, and boulders of graywacke, mudstone, and argillite as well as other lithologies in a matrix of highly contorted black shale overlies the Normanskill Formation E. of Snake Hill and a unit composed mostly of siltstone overlies it W. of Snake Hill. The siltstone unit apparently grades laterally into the Canajoharie Shale. The upper part of the Normanskill Formation and the 2 overlying units are early Trenton in age. The name "Snake Hill Shale" should be abandoned.