Geologic units in Schoolcraft county, Michigan

Black River Limestone (Late Ordovician) at surface, covers 15 % of this area

Black River Limestone

Trenton Limestone (Late Ordovician) at surface, covers 15 % of this area

Trenton Limestone

Burnt Bluff Formation (Early Silurian) at surface, covers 13 % of this area

Burnt Bluff Formation

Manistique Formation (Early Silurian) at surface, covers 11 % of this area

Manistique Formation

Utica Shale (Late Ordovician) at surface, covers 11 % of this area

Utica Shale

Stonington Formation (Late Ordovician) at surface, covers 9 % of this area

Stonington Formation

Prairie du Chien Group (Early Ordovician) at surface, covers 7 % of this area

Prairie du Chien Group

Cataract Formation (Early Silurian) at surface, covers 6 % of this area

Cataract Formation

Queenston Shale (Late Ordovician) at surface, covers 5 % of this area

Queenston Shale

Big Hill Dolomite (Late Ordovician) at surface, covers 4 % of this area

Big Hill Dolomite

Collingwood Limestone (Late Ordovician) at surface, covers 2 % of this area

Collingwood Limestone

Engadine Dolomite (Early Silurian) at surface, covers 2 % of this area

Engadine Dolomite

Trempealeau Formation (Late Cambrian) at surface, covers < 0.1 % of this area

Trempealeau Formation