Middle- and late-Holocene dune reactivation in the Nebraska Sand Hills, USA

Abstract
A combination of optical dating of aeolian sand, and radiocarbon dating of palaeosols and interdune sediments, has allowed some refinements to the chronostratigraphy of the Nebraska Sand Hills. Our results directly confirm previous inferences that multiple phases of aeolian deposition, including megabarchan dune reactivation, occurred within the Sand Hills during the middle and late Holocene. Optical dates on stratified aeolian (barchan dune) sediments from two localities provide ages ranging from c. 6 ka to 20 yr) drought.