Surface and Subsurface Paleokarst, Silurian Lockport, and Peebles Dolomites, Western Ohio

Abstract

The Lockport Dolomite in northwestern and west- central Ohio and the stratigraphically equivalent Peebles Dolomite in southwestern Ohio collectively display a variety of previously unrecognized subsurface and surface paleokarst features. The former include molds, vugs, in situ breccia with corroded clasts, collapsed strata, solution-enlarged joints, internal sediment derived partly from soil, boxwork, and caves. Surface paleokarst features at the top of these units are represented by locally developed pa- leosol and sinks. Erosional relief at the top of the Lockport/Peebles ranges from fractions of an inch (typical) up to 9 feet (2.7 m) (rare). The contact between the Lockport/Peebles and the overlying Greenfield Dolomite is typically a paraconformity in the form of a paleokarst planar erosion surface. As such, the contact can be difficult to recognize, but it is not a fades contact nor is it gradational.