NI93B.HTML Role of in situ cosmogenic nuclides 10Be and 26Al in the study of diverse geomorphic processes

K. Nishizumi, C.P. Kohl, J.R. Arnold, D. Lal, University of California, San Diego

R. Dorn, Arizona State University

J. Klein, D. Fink, R. Middleton, University of Pennsylvania

Earth Surface Processes and Landforms 18 (1993) 407-425

The central premises of applications of the in situ cosmogenic dating method for studying specific problems in geomorphology are outlined for simple and complex exposure settings. In the light of these general models, we discuss the information that can be derived about geomorphic processes, utilizing concentrations of in situ produced cosmogenic radionuclides 10Be (half-life = 1-5 ma) and 26A1 (half-life = 0-7 ma)in a variety of geomorphic contexts: glacial polish and tills; meteorite impact craters; alluvial fans; paleo-beach ridges; marine terraces; sand dunes; and bedrock slopes. We also compare 10Be-26Al data with results obtained by other dating methods. We conclude that the technique of measuring in situ cosmic ray produced nuclides holds promise for quantitative studies of processes and time-scales in a wide range of geomorphological problems.