Image from the Biodiversity Heritage Library.
Contributed by Yale Peabody Museum of Natural History.
| www.biodiversitylibrary.org
Transcription
Look at Arch Creek - porcellanite?
GZlc. Morrison.
Possible criteria for M-FL contact.
1. Base cyltc ss
2. Highest czlc. beds
3. Lowest dk gray or crvb clstu beds
a. Color
b. degree
4. Color, zloize, in clstns.
5. Key beds such as conc. zones, porcellanites.