Field Notebook: WY, SD 1956
Page 139
Image from the Biodiversity Heritage Library. Contributed by Yale Peabody Museum of Natural History. | www.biodiversitylibrary.org
Transcription
Section B. - Cast end of westernmost cut, about 125-50 ft east section A, starting 2f top of hard silty clstn in lower 3' of unit 1 of section A. (1) 17.0 Chiefly covered. Top 1.0+ is purp. red ledge of Fe imprecy very fine sst to siltst up to 4' greenish gray clayey siltst, loc. exposed below it. (2) 12.5 Siltstone and silty claystone, upper 5.0+ is massive gray siltstone, scattered spherulites, becomes darker + loc. shelly near base. Under this 2.0 to 3.0 Fe (red & purple) concret. in siltst. which rather densely spherulitic. Next 2.5+ is dark purple to reddish gray covvng, siltstn + clayey siltst. Bolton 2.0 is gray faintly pink-mottled siltst. (3) 7.5 Sandstone, massive, fine-rg, to thick-bedded, 1/2m to x 1/2m. Weathers to yellow brown vertical ledge with Fe imprecy upper surface (loc rip.mkd.) (4) 2.5 Siltstone, shelly to platy, loc. sandy 68