The lower Cincinnatian Kope Formation in southwestern Ohio and northern Kentucky has been previously studied from the standpoint of paleontology, lithology, and stratigraphy. This study, however, deals with the environment within which the Kope Formation was deposited with some paleoecologic implications.

The Kope Formation is defined as comprising at least 75 to 85% shale and siltstones with thin (5 to 10 cm), laterally discontinuous lenses of predominantly biogenic limestone and biomicrite. Shales are usually fissile while the coarser grained siltstones are more blocky and occasionally rippled or cross-stratified.

The bioclasts in the limestones were measured as discrete grains in an attempt to analyze flow regimes. Degree of sorting and grain roundness varied somewhat but consistently indicated that transport distance and length of time were kept to a minimum. Several of the limestone lenses are megaripple-bedded indicating a higher flow regime.

Faunal diversity is low, generally limited to three or four numerically abundant species. The morphology of the organisms suggests that they were adapted to a soft substrate and probably served as pioneer communities. Burrowing traces were present in the limestones although not as abundantly as in the shale and siltstones.

The environment of the Kope Formation was one of shallow, quiet water in a marine setting where sedimentation was slow and consisted of silt and clay. This setting was periodically interrupted by storm events and changing current patterns which disrupted the isolated communities of organisms and spread their remains laterally, producing carbonate shoals and migrating bioclastic ripples. These events probably represent occasional "instants" of geologic time while the more typical deposition was clay and silt in calmer water.

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