Image from the Biodiversity Heritage Library.
Contributed by Yale Peabody Museum of Natural History.
| www.biodiversitylibrary.org
Transcription
N. South Dakota,
Colbins slope on N.D. Section (set from Steve)
S.E. of Bullhead.
Molbridge member of Pierre: Dark
calcareous clay shale. Weathers
in chunky masses, bluish on
fairly fresh slopes—goes to cluff
on thorough weathering.
Contains group of lenticites,
Set of 3 in upper part:
green-yellow-green, about
1" ± each and about 1½"
apart. Baculites grouldis in
shale. Some cone zones,
upper one barren.
Elk Butte member of Pierre
Non calcareous clay shale
weathering grey on slopes.
Barren from cone in