Severn Formation

Geology

Members: unnamed (23), upper (4), uppermost (7)

Lithologies: not reported (8), "siliciclastic" (1), sandstone (25), "limestone" (21), dolomite (20), lignite (1)

Paleoenvironments: marine indet. (18), terrestrial indet. (2), shallow subtidal indet. (21), marginal marine indet. (1), coastal indet. (14)

Age range: base of the Rhuddanian to the top of the Early/Lower Maastrichtian or 443.40000 to 66.00000 Ma
Collections

Time interval Ma Country or state Original ID and collection number
Rhuddanian443.4 - 440.8Canada (Manitoba) (177635 177646)
Rhuddanian - Aeronian443.4 - 438.5Canada (Manitoba) (177652)
Aeronian440.8 - 438.5Canada (Quebec) (77347)
Aeronian - Telychian440.8 - 433.4Canada (Manitoba) (177636 177637 177638 177647 177648 177653 177656 177657 177661 177662 177663 177674 177675 177676 177677 177685 177686)
Lochkovian419.2 - 410.8Russian Federation (90329)
Cretaceous145.0 - 66.0USA (Maryland) (125141)
Late/Upper Cretaceous100.5 - 66.0USA (Maryland) (125074)
Maastrichtian72.1 - 66.0USA (Maryland) (27562 27563 27564 27565 27566 27567 27568 83331 99439 127085 231271)
Early/Lower Maastrichtian70.6 - 66.0USA (Maryland) (125950)
Late/Upper Maastrichtian70.6 - 66.0USA (Maryland) (4364 4365 4366 4367 4368 4369 4370 4371 4372 4373 4374 4375 4376 82399 82400 82401 82402 82403 82404 82408)