Hell Creek Formation
Geology
Group: Montana
Members: unnamed (542), Breien (10), Little Beaver Creek (1), Lower (6), Middle Sandstone (1), Pretty Butte (4), Upper (13)
Lithologies: not reported (123), "siliciclastic" (1), claystone (14), mudstone (69), "shale" (18), siltstone (43), sandstone (234), conglomerate (9), amber (1)
Paleoenvironments: marine indet. (15), terrestrial indet. (267), coastal indet. (2), estuary/bay (1), fluvial indet. (26), channel lag (20), coarse channel fill (14), fine channel fill (99), "channel" (42), wet floodplain (10), "floodplain" (29), crevasse splay (36), fluvial-lacustrine indet. (1), fluvial-deltaic indet. (1), lacustrine - small (2), pond (14)
Collections