Helena Alexanderson

South-central Sweden is home to a number of small, inactive inland dune fields formed on former glaciofluvialdeltas. A characteristic of these dune fields is the generally transverse shape of the dunes, in stark contrast to therest of Sweden where parabolic dunes are the most common type.One of these dune fields is Bonäsheden in the county of Dalarna. It is the largest continuous dune field in Swedenand covers an area of approximately 15.5 km2. The dune field has the last few years been the target of thoroughinvestigations utilising LiDAR (Light Detection And Ranging) based remote sensing, ground-penetrating radar,luminescence dating and sedimentological field investigations. The results show that the dunes of Bonäsheden andthe adjacent dune field of Skattungheden formed mainly by north-westerly winds shortly after the deglaciation ofthis part of Sweden (10.5 ka), and subsequent events of dune formation were uncommon. Some later episodes ofsand drift did occur, but only as minor coversand deposition.The dune field has had a more complex formation than previously thought; a shift in the wind pattern around 10ka seems to have caused subsequent dunes to have formed by more westerly winds. The reason for this is still notdetermined, but the increased distance to the Scandinavian Ice Sheet would lessen the capacity of katabatic windsto influence the dune field.