Big Snowy Group
Geology
Formations: Heath (27)
Lithologies: not reported (3), lime mudstone (1), "limestone" (23)
Paleoenvironments: marine indet. (1), shallow subtidal indet. (1), open shallow subtidal (4), lagoonal/restricted shallow subtidal (19), estuary/bay (1), lagoonal (1)
Age range: Arnsbergian or 326.90000 to 323.60000 Ma
Collections
| Time interval | Ma | Country or state | Original ID and collection number |
|---|---|---|---|
| Chesterian | USA (Montana) | (136169 157238 236627) | |
| Serpukhovian | USA (Montana) | (154744 157307 157320) | |
| Arnsbergian | USA (Montana) | (90681 116654 116655 116656 116657 116658 116659 116660 116762 116763 116764 130890 226838 227056 227060 227061 227064 227065 227066 232617 232618) |