Results: 1 - 3 of 3
Apr 30, 2012
Open File Report
… by sulphur-stained, dark grey shale of the Westgate Formation. A … bentonite units in the otherwise shale-dominated Fish Scales … the Belle Fourche Formation is shale dominated with silty lenses, …
Sep 26, 2017
Open File Report
… Pliensbachian for the Poker Chip Shale, late Aalenian for the Rock …
Jan 08, 1973
Open File Report
… building stone, quartzite, and shale - potentially the base for a … to 1956, plus some quarrying of shale and limestone. By far the …