Methodological problems in thermoluminescence dating of Weichselian coversand and late Holocene drift sand from the Lutterzand area, E. Netherlands

Abstract

A thermoluminescence dating study of eolian sands was performed for methodological purposes. The twelve samples that were dated include Upper Pleniglacial and Late Glacial coversands as well as late Holocene drift sands from stratigraphically well-known, partly 14C dated exposures, along the Dinkel river in the eastern Netherlands. A new approach was used to determine the equivalent dose (ED) after previous attempts were unsatisfactory. This approach proved promising, enabling to establish an ED value with a small uncertainty. However, the present results show that most of the TL ages of the Weichselian coversands are too low by about 20-40% compared to the radiocarbon dates, although some samples do not disagree with the geological evidence. This problem has also been encountered for coversand samples from Denmark and the reason is not yet fully understood. In spite of the problems that still exist TL proved a powerful method to distinguish between eolian sands with a relatively large age difference. It is still questionable whether TL dating enables a distinction between lithostratigraphical units of the Weichselian coversands in NW Europe.