Niobrara Formation

Primary Lithologies: shale, gray, silty, calcareous to marly. Estimated maximum thickness 50 ft (15 m). Present only in Lyon County.
State Iowa
Name Niobrara Formation
Geologic age Upper Cretaceous; ?Santonian, lower Campanian
Lithologic constituents
Sedimentary > Clastic > Mudstone > Shale (Bed, Calcareous)silty, calcareous to marly

Witzke, Brian J., Anderson, Raymond R., and Pope, John P., 2010, Iowa Geological and Water Survey, DNR, Bedrock Geologic Map of Iowa, OFM-2010-1. Scale 1:500,000.

NGMDB product
Counties Lyon