SGER: An Integrated Study of Lower Mississippian (Kinderhookian-Early Osagena) Earth History: Searching for a Link Between Faunal Turnover, Sea-Level Changes and Carbon Cycling

University Of Iowa, Iowa City IA

Investigators

Abstract

9912385 Matthew R. Saltzman Carbon isotope data from Mississippian carbonate successions of the western and central United States identifies two of the largest positive excursions of the last half-billion years. The excursions appear to reflect episodes of enhanced organic matter burial, perhaps induced by collisional tectonics and sea level changes. The global nature of the carbon isotope excursions is, however, unproven and the proposed research is focused on characterization of Mississippian seawater carbon isotope values in the western United States (Nevada, Missouri) and western Europe (Belgium). Conodont faunas in these regions that were widely separated in the Mississippian allow for precise intercontinental correlation of marine sedimentary successions. This proposal represents a venture into an emerging research area aimed at understanding causal links between previously documented changes in sea level and glacigenic sedimentation during the Mississippian and changes in carbon cycling indicated by excursions in carbon isotopes. The carbon isotope excursions may also be used as a tool in correlation alongside the established conodont zonation. Previous carbon isotope studies have worked at the stage or formation level of resolution and thus provide limited constraints on the timing of changes in carbon cycling with respect to sea level and faunal turnover.