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Salt crystal cavities in a bed of marlstone suggesting interlock plates of anhydrite. Rio Blanco County, Colorado. circa 1925. Plate 6-B, U.S. Geological Survey. Professional paper 168. 1931.
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Microfossil of the oil shale of the Green River formation: spore similar to the conidia of Brachysporium sp. Colorado or Utah. 1925. Plate 20, figure 7, U.S. Geological Survey. Professional paper 168. 1931.
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Transverse section of the pitted Chlorellopsis reef shown in Bradley 205; showing the cores of sand filled ringed pits and the conoidal excrescences at their lower ends. This also shows the marked thickening of the algal layers between pit cores, natural size. Specimen is from about 138 feet below the top of the Green River formation in NE 1/4 SE 1/4 sec. 30, T. 4 N., R. 96 W. Moffat County, Colorado. August 1, 1925. Plate 38-A in U.S. Geological Survey. Professional paper 154. 1929.
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Polished section of a algal cobble, showing a large subangular limestone nucleus and three distinct stage of growth, natural size. Specimen is from transitional beds between the Tipton tongue of the Green River formation and the Cathedral Bluffs tongue of the Wasatch formation in NE 1/4 SE 1/4 sec. 15, T. 25 N., R. 102 W. Sweetwater County, Wyoming. 1923. Plate 46-A in U.S. Geological Survey. Professional paper 154. 1929.
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Polished transverse section of reef shown in Bradley photo 209; showing alternate algal and inorganic layers, the irregular light colored layers consists of the molds of Chlorellopsis coloniata and typical spongy algal deposit. The black and gray finely banded layers are of inorganic origin and owe their dark color to disseminated pyrite. Enlarged 3 diameters. Compare with the photomicrograph of thin section of part of the same reef shown in Bradley photo 242. Specimen is from near the base of the Tipton tongue of Green River formation in NW 1/4 16, T.24 N., R. 101 W. Sweetwater County, Wyoming. 1923. Plate 45-A in U.S. Geological Survey. Professional paper 154. 1929.
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