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Storm Deposited Fish Debris In The Cretaceous Mowry Shale Near Vernal, Utah, Alvin Anderson, Bart Kowallis

Bart J Kowallis

Isolated, lens-shaped accumulations of fi sh bones, scales, teeth, and coprolites in a sandy matrix occur along a few bedding planes within the Cretaceous Mowry Shale in an outcrop along Highway 191 north of Vernal, Utah. These accumulations have previously been interpreted to be large coprolites or regurgitate material, but are actually storm lag deposits in a sediment-starved basin. Accumulations (lenses) vary in size: the largest measured is 15 x 10 cm in plan view and 2 cm thick. Matrix in these lenses consist of fine-grained, well-rounded quartz grains that are absent in the surrounding shale layers. The disarticulated fossil …