Jacob Bruihler will give his master’s thesis defense, “Dating Late Quaternary Alluvial Fills in the Platte River Valley using Optically Stimulated Luminescence Dating,” at 8:30 a.m. April 13 in Hardin Hall 901.
Bruihler summarizes his research:
“Underlying the Platte River Valley in Nebraska, alluvial fills record the geologic history of the Platte River in the late Quaternary. Sediment cores were recovered from these alluvial deposits in rough transects along the Platte River floodplain near the towns of North Platte and Kearney, Nebraska. Optically Stimulated Luminescence (OSL) dating was used to determine burial age of recovered sediments and to quantify the thicknesses of Pleistocene and Holocene age alluvial fill in the two study areas. OSL ages were calculated using the single aliquot regenerative procedure on quartz sand grains. Based on results from OSL dating, burial ages ranged from approximately 1 to 68 ka. Holocene age alluvium in both study sites is present to depths of up to 8 meters below the present floodplain. Late Pleistocene age sediment that can be dated with OSL is found at depths of up to 15 meters below the present floodplain. Our geochronology indicates there are considerable differences in age with depth at the two study sites. Evidence suggests that both study sites experienced aggradation in the late Pleistocene, followed by entrenchment of the alluvial fills during the late Holocene.”
More details at: http://go.unl.edu/vwqs