Late Pleistocene through Holocene landscape evolution of the White River Badlands, South Dakota

Abstract

Badlands are common arid and semiarid landscapes long recognized in slope development and erosion rate studies by preeminent geomorphologists including Gilbert, Davis, and Schumm. The trip described here will examine in detail Quaternarystrata and landscape evolution in arguably the most famous badlands, the White River Badlands of South Dakota, which were pivotal during development of vertebrate paleontology in North America. Geologists have collected fossils from the White River Group there nearly every field season since the mid-1800s; however, until recently, little work was reported on the extensively exposed Quaternary strata. The White River Badlands are also a proposed dust source for the widespread PeoriaLoess of the Central Great Plains. The research highlighted on this trip includes (1) luminescence and radiocarbon ages from late Pleistocene through Holocene eolian sand, (2) radiocarbon ages from Holocene eolian cliff-top deposits, (3) luminescenceages from late Pleistocene fluvial silts, (4) radiocarbon ages of late Holocene fluvial silts, and (5) cosmogenic ages on ventifacts from the adjoining upper prairie. These new studies will facilitate discussions, including (1) late Quaternary paleoenvironments,(2) late Quaternary fluvial incision rates and episodes, (3) up-wind sediment supply of late Quaternary nonglaciogenic loess, (4) landscape evolution spanning late Pleistocene tableland through late Holocene sod table development, and (5) modern erosion-pedimentation rates.