14-6 Conodonts from the Chattanooga (Upper Devonian) and Floyd (Carboniferous) formations from the southern Appalachian Basin of Alabama, assemblages and lag surfaces from black shale in drill cores

Abstract:

Conodonts were recovered from bedding planes in black shale intervals from two 10 cm (4 inch) diameter drill cores from central Alabama. In the Cain 6-6 #1 core the occurrence of Palmatolepis bogartensis? (Stauffer 1938), Pa. extensa Ziegler and Sandberg 1990?, Pa. rhenana Bischoff 1956, and Pa. boogaardi Klapper and Foster 1993 were recovered from a 3.5 m thick interval in the Chattanooga Shale, indicative of the highest Frasnian Zone 13.  In the Weyerhaeuser 2-43-2402 core Pa. per. perlobata, Pa. clarki, and Pa. del. delicatula in a lag bed in the Chattanooga Shale indicates the Pa. min. minuta to Pa. crepida Zone. These conodonts indicate Frasnian and Famennian strata in the Chattanooga Shale in the southern Appalachian Basin of the Alabama subsurface. The Floyd Formation (Carboniferous) in the Weyerhaeuser 2-43-2402 core contained a full and an incomplete assemblage of Gnathodus bilineatus ssp., and a single incomplete assemblage of two Sb1 or Sb 2 elements, two indeterminate S elements, and one Sc1 element from an Idioprioniodus sp. The morphology of the Idioprioniodus sp. specimen, as well as the time constraints provided by G. bilineatus, make the species indeterminate and possibly transitional between I. healdi and I. conjunctus.

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