NSF Award
9910197
9910197 John Holbrook, Southeast Missouri State University<br/><br/><br/>Anomalous biotic and physical trends in mid-Cretaceous strata of the northern U.S. Western Interior basin have prompted some authors to propose a brief connection between the northern/Boreal and southern/Tethyan arm of the Western Interior sea at the time of the Early/Late Cretaceous boundary, even though no direct physical evidence for such a connection is yet cited. The proposed research will test this hypothesis by applying sequence stratigraphic, paleontologic, palynologic, and chemostratigraphic techniques to mid-Cretaceous strata in the central Western Interior where a connection may be recorded. The study aims to clarify several stratigraphic issues in economically important mid-Cretaceous strata of the United States and Canada. Its broader implications are to reevaluate Cretaceous faunal mixing and evolutionary trends, and to constrain the enigmatic Lower/Upper Cretaceous boundary in North America. The resultant integrated stratigraphic framework is also the first step in testing the currently published hypothesis that the proposed brief marine connection is responsible for the regional anoxic event, and associated changes in the global carbon cycle, recorded in mid-Cretaceous strata of Canada. This is particularly important to modem climate modeling, because many modem transgressing oceans are separated by only a low and narrow isthmus.
