2006 Philadelphia Annual Meeting (22–25 October 2006)

Paper No. 24
Presentation Time: 8:00 AM-12:00 PM

LATE QUATERNARY GEOCHRONOLOGY AND STRATIGRAPHY OF THE EASTERN CASPER DUNE FIELD, CASPER, WYOMING, U.S.A


HALFEN, Alan Frederick, Geography, University of Wisconsin Milwaukee, 444 Bolton Hall, 3210 North Maryland Ave, Milwaukee, WI 53211, afhalfen@uwm.edu

Geochronologies of North American Great Plains eolian dune fields are significant sources of paleoclimate documentation. Although many geochronologies have been developed in the region, several dune fields have not been studied. These dune fields are commonly smaller and less studied then larger well know fields. Wyoming contains several dune fields relatively understudied for their geochronology including the Eastern Casper Dune Field. Exploring dune stratigraphy will also provide insights into late Quaternary landscape stability. 10 meters of exposed dune stratigraphy yields several buried A horizon soils accompanied by well sorted C horizons. Extracted charcoals provide age estimates for buried soils. OSL analysis provides age estimates for quartz dominated C horizons. Dune stratigraphy suggests possible active synchronisms with other Great Plains dune fields, or it may illustrate a time transgression across the central Great Plains. Extending the Casper Dunes geochronological record provides further information about the landscape stability of Great Plains late Quaternary eolian deposits.