Luminescence dating of Holocene aeolian sand movement, Thy, Denmark

We report on the application of optically stimulated luminescence dating to an investigation of the frequency of periods of aeolian sand movement and dune formation. On the coast of Thy, Holocene aeolian sediments, interleave d with peaty palaeosols, form some of the most complete successions known i n western Denmark. Samples were taken from a coastal exposure, and an inlan d archaeological site. Dosimetry was based on laboratory gamma spectrometry , and quartz luminescence measurements used the single-aliquot regenerative -dose protocol, and 470 +/- 30 nm stimulation. The sand samples cover an ag e ranging from about 100 years to 4500 years; the youngest dates give us co nfidence that the material was well bleached at deposition. Good agreement was obtained with the radiocarbon palaeosol ages. We identify three main pe riods of aeolian sand movement, starting at about 4200, 2700 and 900 years ago; at least during the latter two periods significant aeolian sand moveme nt occurred. All three phases of aeolian activity were separated by long pe riods of stability and soil formation. A more recent episode of dune format ion, restricted to the coast and beginning less than 200 years ago, may hav e been triggered by modern coastal erosion. (C) 2000 Elsevier Science Ltd. All rights reserved.