Geologic units in Wabasha county, Minnesota

Lower Ordovician (Lower Ordovician) at surface, covers 71 % of this area

Dolostone, sandy to silty dolostone, and sandstone; includes the Shakopee Formation and Oneota Dolomite of the Prairie du Chien Group.

Middle and Upper Cambrian (Middle and Upper Cambrian) at surface, covers 14 % of this area

Sandstone, siltstone, and shale; includes the Wonewoc Sandstone, Eau Claire Formation, and Mt. Simon Sandstone.

Upper Cambrian (Upper Cambrian) at surface, covers 13 % of this area

Sandstone, siltstone, shale, and dolostone; includes the Jordan Sandstone and St. Lawrence Formation, and the Mazomanie, Lone Rock, and Davis Formations of the Tunnel City Group.

Middle and Upper Ordovician (Middle and Upper Ordovician) at surface, covers 2 % of this area

Shale, dolomitic limestone, and sandstone; includes the Decorah Shale of the Galena Group, the Platteville and Glenwood Formations, and the St. Peter Sandstone.

Cambrian, undivided (Cambrian) at surface, covers 0.2 % of this area

Sandstone with some dolomite and shale, undivided; includes Trempealeau, Tunnel City, and Elk Mound Formations