14-4 Conodonts from the Cleveland Shale, Famennian, Upper Devonian, from the Subsurface of Ohio

Abstract:

Conodonts were recovered from the Upper Devonian Cleveland Shale Member of the Ohio Shale from three drill cores: OGS 2811 (Ross County: RC), OGS 2736 (Delaware County: DW), and OGS 6426 (Cuyahoga County: CH) that form a transect from south central Ohio (RC) to northeastern Ohio (CH). Where the Cleveland Shale thins south to north from 24 m to 7 m thick.  Conodonts and fish remains were recovered from bedding plane surfaces in the split 5 cm (2 inch) diameter core.  In RC Palmatolepis maxima was recovered from the uppermost Three Lick Bed, as well as Bispathodus stabilis, Branmehla ampla, and Br. inornata higher in the Cleveland Member.  In DW Bi. aculeatus aculeatus and Pa. schindewolfi were recovered.  In CH the Skinners Run Pyrite Bed is well developed at the base of the Cleveland Member, yielding diverse conodonts.  A lag containing numerous Bispathodus and Branmehla was found 2 m above the base, and Bi. aculeatus aculeatus and Br. ampla were recovered near the top.  The first occurrence of Bi. aculeatus anteposicornis in the upper Three Lick Bed indicates the aculeatus Zone, no higher zone indicating conodonts were recovered from the Cleveland Member.  The long ranging taxa found last occur in the ultimus Zone, or continue into the lower Carboniferous.

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