Geologic units in Boone county, Kentucky

Bull Fork Formation (Ordovician) at surface, covers 36 % of this area

Bull Fork Formation

Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided (Ordovician) at surface, covers 33 % of this area

Ashlock Formation, Grant Lake and Calloway Creek Limestones, and Fairview Formation, undivided

Garrard Siltstone and Kope and Clays Ferry Formations, undivided (Ordovician) at surface, covers 21 % of this area

Garrard Siltstone and Kope and Clays Ferry Formations, undivided

Glacial deposits, undifferentiated (Pleistocene to Holocene) at surface, covers 8 % of this area

Glacial deposits, undifferentiated; shown locally

Alluvium (Pleistocene to Holocene) at surface, covers 2 % of this area

Alluvium; includes glacial deposits along the Ohio River and its tributaries west of Cannelton locks

Kope Formation (Ordovician) at surface, covers 0.1 % of this area

Shale and thin skeletal limestone

Lexington Limestone (Ordovician) at surface, covers < 0.1 % of this area

Micritic and skeletal limestone

Point Pleasant Formation (Ordovician) at surface, covers < 0.1 % of this area

Limestone (60%) and shale (40%) interbedded; gray to bluish gray weathers light gray; planar to lenticular, thin to medium bedded; 0 to 80 feet thick.