Macrostrat
Columns
Brown County, South Dakota
Age
(
Ma
)
70
120
150
170
452
458
470
490
2,500
2,700
Cenozoic
Paleogene
Paleocene
Mesozoic
Cretaceous
Late Cretaceous
Early Cretaceous
Mesozoic
Cretaceous
Early Cretaceous
Jurassic
Late Jurassic
Middle Jurassic
Early Jurassic
Paleozoic
Ordovician
Late Ordovician
Middle Ordovician
Paleozoic
Ordovician
Middle Ordovician
Early Ordovician
Cambrian
Furongian
Series 3
Paleoproterozoic
Siderian
Neoarchean
Pierre Shale
Niobrara Formation
Carlile Formation
Greenhorn Formation
Graneros Shale
Dakota Formation
Skull Creek Shale
Inyan Kara Group
Undifferentiated
Red River Formation
Roughlock Member of Winnipeg Formation
Icebox Member of Winnipeg Formation
Black Island Member of Winnipeg Formation
Deadwood Formation
Unnamed
22.51
Myr
276.3
Myr
10.65
Myr
2
Gyr
Brown County, South Dakota
–
Northern Mid-Continent
#174
,
project 1
,
show in map
.