Bateman, M.D., Thomas, D.S.G. and Singhvi, A.K. (2003) Extending the aridity record of the Southwest Kalahari: current problems and future perspectives. Quaternary International, 111 (1). pp. 37-49. ISSN 1040-6182
Abstract
An extensive luminescence-based chronological framework has allowed the reconstruction of expansions and contractions of the Kalahari Desert over the last 50 ka. However, this chronology is largely based on near-surface pits and sediment exposures. These are the points on the landscape most prone to reactivation and resetting of the luminescence dating ‘clock’. This is proving to be a limiting feature for extending palaeoenvironmental reconstructions further back in time. One way to obviate this is to sample desert marginal areas that only become active during significant arid phases. An alternative is to find and sample deep stratigraphic exposures. The Mamatwan manganese mine at Hotazel in the SW Kalahari meets both these criteria. Luminescence dating of this site shows the upper sedimentary unit to span at least the last 60 ka with tentative age estimates from underlying cemented aeolian units dating back to the last interglacial and beyond. Results from Mamatwan are comparable to new and previously published data from linear dunes in the SW Kalahari but extend back much further. Analysis of the entire data set of luminescence ages for the SW Kalahari brings out important inferences that suggest that different aeolian forms (1) have been active over different time scales in the past, (2) have different sensitivities to environmental changes and (3) have different time scales over which they record and preserve the palaeoenvironmental record. This implies that future optically stimulated luminescence work and palaeoenvironmental reconstructions must consider both site location and its relationship to desert margins and sediment depositional styles, so that the resolution and duration of the aridity record can be optimally understood.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | Copyright © 2003 Elsevier Science Ltd.This is an author produced version of a paper which was subsequently published in Quaternary International. This paper has been peer-reviewed but does not contain final published proof-corrections or journal pagination. |
Dates: |
|
Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > University of Sheffield Research Centres and Institutes > Sheffield Centre for International Drylands Research The University of Sheffield > Faculty of Social Sciences (Sheffield) > Department of Geography (Sheffield) |
Depositing User: | mark bateman |
Date Deposited: | 17 Mar 2006 |
Last Modified: | 07 Jun 2014 01:22 |
Published Version: | http://dx.doi.org/10.1016/S1040-6182(03)00013-2 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1016/S1040-6182(03)00013-2 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:1071 |