Climate oscillations and tephrochronology in eastern middle Sweden during the last glacial-interglacial transition

Two sequences spanning the last glacial-interglacial transition in southern Ostergotland, eastern middle Sweden have been investigated for high-resolu tion vegetation change and tephrochronology. Organic carbon and pollen anal ysis indicates that the Younger Dryas-Preboreal climatic transition was cha racterised by at least one well-defined oscillation or possibly two shorter climatic oscillations. The Vedde Ash (ca. 12 000 GRIP yr BP or ca. 10300 C -14 yr BP) has been identified at both sites, significantly increasing the known distribution of this marker horizon. In addition, a previously unreco rded rhyolitic tephra of Icelandic origin has been identified at ca. 9000 C -14 yr BP. The expansion of Corylus into southern Ostergotland is estimated to be ca. 9400 C-14 yr BP. Copyright (C) 1999 John Wiley & Sons, Ltd.