Mt. Simon Sandstone

Subcrops beneath Mississippi River alluvium in northeastern Allamakee County; surface exposures absent. Overlies erosional surface on Precambrian granitic basement rocks. Primary lithology: sandstone, very fine to very coarse grained, part iron-stained. Minor: shale, silty to sandy, gray, red, green; quartz granules; granitic pebbles. Thicknesses: 365-405 ft (111-123 m).
State Iowa
Name Mt. Simon Sandstone
Geologic age Middle Cambrian undifferentiated
Lithologic constituents
Sedimentary > Clastic > Sandstone (Bed)very fine to very coarse grained, part iron-stained
Sedimentary > Clastic > Mudstone > Shale (Bed)silty to sandy, gray, red, green

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 Allamakee