Field Notebook: CO 1951a
Page 29
Image from the Biodiversity Heritage Library. Contributed by Yale Peabody Museum of Natural History. | www.biodiversitylibrary.org
Transcription
silty 2.5 var. clays: red, gray & greenish: silty clay: 2 1/2 -> 3' thick (argill siltstone and sandy siltstone 2.3 <- gently fracturing; weathers light gray) underlain by more ves. clay. stup here Break in section: Dak-Granerus transition beds: 6'+ from top of massive first ss of Dakota. obscured by slopewash lower 8' 15.0 argill so interlidd with shale -> thin beds platy sandstone fine grained gray, weathering to light gray FC- staining on joint places and some bedding surfaces. Beds up to .5' thick average about .2' thick. Centruncated partings of sandy shale and calcary sandstone. upper 7' similar to lower 8' but increasingly shaly upward with sandstones becoming finely lam- nated and grading upwards into siltstones. Resistable argill. siltstone bed .5' thick cape interval. 5.71 dark gray clayey shale, weathers a light gray with rust staining on surface. No fossils observed. 0.3' Bentonit [0.8 hard gray, light gray weatherin argill siltston.