Geologic units in Mackinac county, Michigan

Engadine Dolomite (Early Silurian) at surface, covers 43 % of this area

Engadine Dolomite

Burnt Bluff Formation (Early Silurian) at surface, covers 22 % of this area

Burnt Bluff Formation

Manistique Formation (Early Silurian) at surface, covers 18 % of this area

Manistique Formation

Point Aux Chenes Shale (Late Silurian) at surface, covers 12 % of this area

Point Aux Chenes Shale

Bois Blanc Formation (Early Devonian) at surface, covers 3 % of this area

Bois Blanc Formation

Mackinac Breccia (Early Devonian) at surface, covers 1 % of this area

Mackinac Breccia

Cataract Formation (Early Silurian) at surface, covers 0.7 % of this area

Cataract Formation

Sainte Ignace Dolomite (Late Silurian) at surface, covers 0.5 % of this area

Sainte Ignace Dolomite

Queenston Shale (Late Ordovician) at surface, covers 0.2 % of this area

Queenston Shale

Stonington Formation (Late Ordovician) at surface, covers < 0.1 % of this area

Stonington Formation

Big Hill Dolomite (Late Ordovician) at surface, covers < 0.1 % of this area

Big Hill Dolomite