Skip to main content
U.S. flag

An official website of the United States government

Last Glacial loess in the conterminous USA

January 1, 2003

The conterminous United States contains an extensive and generally well-studied record of Last Glacial loess. The loess occurs in diverse physiographic provinces, and under a wide range of climatic and ecological conditions. Both glacial and non-glacia lloess sources are present, and many properties of the loess vary systematically with distance from loess sources. United States' mid-continent Last Glacial loess is probably the thickest in the world, and our calculated mass accumulation rates (MARs) are as high as 17,500 g/m2/yr at the Bignell Hill locality in Nebraska, and many near-source localities have MARs greater than 1500 g/m2/yr. These MARs are high relative to rates calculated in other loess provinces around the world. Recent models of LastGlacial dust sources fail to predict the extent and magnitude of dust flux from the mid-continent of the United States. A better understanding of linkages between climate, ice sheet behaviour, routing of glacial meltwater, land surface processes beyond the ice margin, and vegetation is needed to improve the predictive capabilities of models simulating dust flux from this region.

Publication Year 2003
Title Last Glacial loess in the conterminous USA
DOI 10.1016/S0277-3791(03)00169-0
Authors E. Arthur Bettis, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle
Publication Type Article
Publication Subtype Journal Article
Series Title Quaternary Science Reviews
Index ID 70038742
Record Source USGS Publications Warehouse
USGS Organization Geology and Environmental Change Science Center