Judith River Formation

Geology

Group: Montana

Members: unnamed (83), Coal Ridge (12), McClelland Ferry (9), Woodhawk (1)

Lithologies: not reported (59), "siliciclastic" (7), claystone (4), mudstone (10), "shale" (1), siltstone (3), sandstone (26), coal (1), lignite (1), ironstone (1)

Paleoenvironments: terrestrial indet. (73), marginal marine indet. (1), coastal indet. (3), estuary/bay (2), delta plain (2), deltaic indet. (5), fluvial indet. (2), channel lag (3), fine channel fill (1), "channel" (2), crevasse splay (4), levee (1), mire/swamp (1), fluvial-deltaic indet. (1), lacustrine indet. (4)

Age range: base of the Late/Upper Campanian to the top of the Late/Upper Maastrichtian or 83.50000 to 66.00000 Ma
Collections

Time interval Ma Country or state Original ID and collection number
Late/Upper Campanian83.5 - 70.6USA (Montana) (14447 14452 55274 69150 156538 190394 215798 215799 230098 230102 231025)
Middle Campanian83.5 - 70.6USA (Montana) (14437 14482 26779 46121 69152 69281 73891 167804 216964 227264 228490 229345 235325)
Middle Campanian - Late/Upper Campanian83.5 - 70.6Canada (Saskatchewan) (14493 14494 75030)
Middle Campanian - Late/Upper Campanian83.5 - 70.6USA (South Dakota) (142509)
Middle Campanian - Late/Upper Campanian83.5 - 70.6USA (Montana) (14432 14434 14435 14445 14446 14448 14449 14450 14457 14459 14460 14461 14462 14468 14470 14483 14490 14491 14492 23549 23551 32404 34016 46122 46123 46124 48620 49001 50825 50826 50827 50828 50829 50830 50906 50907 50909 51682 51683 58156 59217 60518 61452 64643 64788 69153 69161 69177 69178 69213 69250 69251 69252 69253 69450 69624 122333 128455 128560 140916 142328 142495 142506 142510 142511 142512 167800 167801 167802 177026 177027 177030 177498 194654 206062 222122)
Late/Upper Maastrichtian70.6 - 66.0USA (Montana) (229841)