Abstract: Wenlock Conodont Chronostratigraphy and Sequences of the Appalachian Basin in New York, Ohio, and Tennessee

KLEFFNER, MARK A.
The Ohio State University at Lima, Lima, OH

A Wenlock (Silurian) conodont chronostratigraphy developed for strata in New York, Ohio, and Tennessee, provides a means to extend recognition of sequences identified for the upper part of the Clinton Group and the Lockport Group in the Appalachian Foreland Basin by Carlton Brett, William Goodman, and Steven LoDuca, into additional areas of the Appalachian Basin. Sequence IV is comprised of the Williamson Shale and Rockway Dolomite (or their equivalents) in New York, the Estill Shale in southern Ohio, the Dayton Formation in western Ohio, and the basal Maddux Member of the Wayne Formation in central Tennessee. It is within the Pterospathodus amorphognathoides Chronozone. Sequence V is comprised of the Irondequoit Limestone, Rochester Shale, and DeCew Dolomite (or their equivalents) in New York, the Bisher Formation and lower part of the Lilley Formation in southern Ohio, the Osgood and Laurel Formations (including the Massie Member) in western Ohio, and the Maddux Member of the Wayne Formation in central Tennessee. It is within the Kockelella ranuliformis and lower part of the Ozarkodina sagitta rhenana Chronozones. Sequence VI is comprised of the Goat Island, Eramosa, and Guelph Formations (or their equivalents) in New York, the upper part of the Lilley Formation and Peebles Dolomite in southern Ohio, the Euphemia, Springfield, and part/all of the Cedarville Dolomites of western Ohio, and the Maddux, Waldron, Lego, and possibly part/all of the Dixon Members of the Wayne Formation in central Tennessee. Sequence VI (Wenlock part) is within the 0. sagitta rhenana, 0. sagitta sagitta, 0. bohemica, and lower part of the K. variabilis Chronozones. At present, the Wenlock/Ludlow boundary can only be recognized with confidence in central Tennessee, near the base of the Dixon Member.

AAPG Search and Discovery Article #90930©1998 AAPG Eastern Section, Columbus, Ohio