Geologic units in Blackford county, Indiana

Pleasant Mills Formation (Silurian) at surface, covers 39 % of this area: Pleasant Mills Formation - Dolomite, limestone, and argillaceous dolomite
Lithology: dolostone (dolomite); limestone
Ordovician rocks, undifferentiated (Silurian) at surface, covers 10 % of this area: Ordovician rocks, undifferentiated - Shale and limestone; upper part of Maquoketa Group in deep buried valleys; Maquoketa to upper part of Knox Supergroup in Kentland area
Lithology: shale ; limestone; dolostone (dolomite)
Wabash Formation (Silurian) at surface, covers 15 % of this area: Wabash Formation - Limestone, dolomite, and argillaceous dolomite
Lithology: limestone; dolostone (dolomite)
Louisville Limestone through Brassfield Limestone (Silurian) at surface, covers 36 % of this area: Louisville Limestone through Brassfield Limestone - Sexton Creek Limestone at base in Kentland area and on cross-section
Lithology: limestone