| Research question
When did sand drift occur in the Vomb basin in central Skåne and what were the triggering mechanisms behind the events?
Background and aim
Sand drift can potentially have large impact on the landscape and on farming and other human activities. In Sweden, Skåne is one of the most affected areas, and the destructive effect of wind erosion has been documented in historical and recent records. Geological studies in southern Sweden show that sand drift has occurred also further back in time, but the timing for these events is poorly known.
Windblown sediments are also interesting to study since they contain a record of environmental change, which in Sweden is largely unused. Sand dunes and other types of aeolian deposits can reveal information on past wind directions and changes in climate, vegetation cover and water-level due to natural or human influence. Again, dating of the deposits is crucial to reconstructing past environments.
Two units of windblown sand, separated by a paleosol, have been identified in a gravel pit near Blentarp in Skåne during field course work by the Department of Geology, Lund University. The Blentarp gravel pit is situated in the Vomb basin, which is an area dominated by sandy glacial river and lake deposits. It is thought, but not known, that the older sand at Blentarp was deposited when the Scandinavian ice sheet had melted away and the glacial lake in the Vomb basin had drained, approximately 15 000 years ago. The younger sand is expected to be of historical age.
I plan to sample and date the aeolian deposits at Blentarp, using a technique called optically stimulated luminescence (OSL) dating, which is well suited for aeolian sediments. The results will show when the sediments were deposited and I will be able to correlate the events to other records of environmental change and human impact and thereby determine probable causes for the sand drift events.
My aim is to get a better understanding of aeolian processes in formerly glaciated areas, as exemplified by my study area in Skåne, and thereby be able to discuss causes of wind erosion and deposition and their effects on the landscape. Knowledge gained in this study can be used for example in reconstructions of late glacial and Holocene climate, but also for landscape management, e.g. in preventing soil erosion and unwanted aeolian activity.
Method
During 3-4 days of field work I will do geological and geomorphological mapping of the aeolian deposits in and around the Blentarp gravel pit to determine their extent and characteristics. Open sections in the gravel pit, where the windblown sand is exposed, will be studied and documented. Samples for dating by radiocarbon and by optically stimulated luminescence (OSL) will be taken. Most of my work will focus on OSL dating and will be carried out in the laboratory. I will work at the Lund Luminescence Laboratory, but within this project I will also visit the Nordic Laboratory for Luminescence Dating in Risö, Denmark for discussions and special OSL analyses that are not possible to do in Lund.
Budget
Field work (rental car, petrol, 4 days) 1500 kr
Radiocarbon dating (2 á 2300 kr) 4600 kr
Travel to and food/lodging at Risö (1 week) 2300 kr
Total sum 8400 kr
|