9513128 Huff This U.S.-Argentina collaborative research effort will test two paleogeographic reconstructions attempting to explain an apparent early Paleozoic connection between North and South America. The alternatives would either have Laurentia colliding with western South America during the Middle Ordovician or a piece of Laurentia breaking off later in Cambrian time and drifting south, accreting to the western margin of South America. The collaboration between Warren Huff of the University of Cincinnati, Dennis Kolata of the Illinois State Geological Survey, Stig Bergstrom of Ohio State University, and Carlos Cingolani of the Universidad Nacional de la Plata together with 7 other Argentine investigators will create a team in interrelated specialties to carry out the test of the two hypotheses. Recent finds of beds of K-bentonites suggest the possibility of determining the stratigraphic and areal distribution of Ordovician volcanic ash beds and their ability to resolve the alternative hypotheses. The proposed research will produce an international collaboration through field work in Argentina and extensive data analysis carried out in both the U.S. and Argentina. To assure successful field studies, Argentine specialists in structure and tectonics, graptolites, petrology and geochemistry, paleontology, and stratigraphy have been included. One graduate student will also travel to Argentina to participate in the project. ****
