Environmental conditions and paleowind directions at the end of the Weichselian Late Pleniglacial recorded in aeolian sediments and geomorphology (Twente, Eastern Netherlands)

Ko (J.) van Huissteden; Jacques C.G. Schwan; Mark D. Bateman

doi:10.1017/S0016774600022277

Ko (J.) van Huissteden Vrije Universiteit, Faculty of Earth Sciences, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
Jacques C.G. Schwan Mauritsstraat 35, 3583 HH Utrecht, The Netherlands
Mark D. Bateman Sheffield Centre for International Drylands Research, Department of Geography, Winter St., University of Sheffield Sheffield S10 2TN Great Britain

DOI: https://doi.org/10.1017/S0016774600022277

Keywords: aeolian features, periglacial features, palaeoclimate, Weichselian, Last Glacial Maximum, Netherlands

Abstract

The Late weichselian Pleniglacial wind regime in the eastern Netherlands is reconstructed by means of landform and sedimentological analysis. This analysis involves aeolian and fluvial landforms in the Dinkel river valley in the Twente region. The aeolian deposits considered here date from the Last Glacial Maximum (approximately 22 ka) to the start of the Belling Interstadial at 14.7 ka.

A major event in this period is the formation of a cryoturbation level caused by permafrost degradation, overlain by an erosional hiatus dated between 21 and 17 ka. Both features are attributed to a period of warmer and moister climate, causing permafrost degradation and erosion by surficial runoff. Thereafter aeolian activity prevailed under relatively arid conditions. A deflation surface was formed, the Beuningen Gravel Bed. This deflation surface is present in many Weichselian sections in the Netherlands and the adjacent parts of Belgium and Germany. The deflation occurred concurrently with deposition of coversand at other places.

The morphology of the coversand-landscape in the Dinkel valley was controlled by the relief of the pre-existing floodplain and the wind pattern. Coversand ridges consisting of low dunes accumulated near the margins of the active channel belt. Relatively thick sand sheets occur in the leesides of the ridges, thin sand sheets are found at greater distance.

Mainly westerly sand-transporting winds operated during winter and summer. In winter aeolian deposition occurred by frequent and strong easterly winds also. On the smallest, local scale, the pattern of deposition was determined by the topography and moisture of the receiving surface.

Coversand deposition came to an end with the formation of a sand sheet under relatively warm and less arid conditions. Coversand deposition continued into the Belling Interstadial; colonization of the coversand surface by vegetation probably has been delayed by nutrient-poor conditions.