Appalachian sedimentary cycles during the Pennsylvanian: Changing influences of sea level, climate, and tectonics
Stephen F Greb, Jack C Pashin, Ronald L Martino, Cortland F Eble, 2008. "Appalachian sedimentary cycles during the Pennsylvanian: Changing influences of sea level, climate, and tectonics", Resolving the Late Paleozoic Ice Age in Time and Space, Christopher R. Fielding, Tracy D. Frank, John L. Isbell
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Various orders of marine flooding surface–bounded depositional sequences are recognized in coal-bearing, Pennsylvanian-age strata of the greater Appalachian Basin. The best preserved of these from the Lower Pennsylvanian are in the southern and central Appalachians; Middle Pennsylvanian cyclothemic sequences are best preserved in the central Appalachians; and Upper Pennsylvanian cyclothemic sequences are best preserved in the northern Appalachians. Palynological and lithostratigraphic correlations to global time scales have been used to infer eustatic controls on accumulation of cyclothem-scale sequences in each of these areas, albeit with significant tectonic and climatic overprints. New U-Pb absolute age dates from upper Lower Pennsylvanian and Middle Pennsylvanian tonsteins in the central basin can be used to infer an average maximum duration of 0.1 m.y. for minor transgressive-regressive depositional cycles, which supports the possibility of short eccentricity-driven eustatic influences on sedimentation. Although glacial eustasy influenced Pennsylvanian sedimentation throughout the basin, the thickness, lateral continuity, and constituent facies of high-frequency depositional cycles were strongly influenced by changing rates of tectonic accommodation in at least three depocenters, sediment flux, and changing paleoclimate.