This is a typical carbonate hardground from the Upper
Ordovician of the Cincinnati region. The hardground is recognizable
in this outcrop because of its bioerosion features, namely the
thin, silt-filled holes perpendicular to bedding. These holes
are given the ichnogenus Trypanites. This outcrop of the
Grant Lake Limestone is near Washington, Kentucky. (Back
to outline or next hardground.)
|