The deglaciation and vegetational history of a former ice-damned lake area at Skåbu, Nord-Fron, Southern Norway.

Abstract

Cores obtained from a small peat bog within the area of a former ice-dammed lake show that 1.7 m of silt were deposited during the ice lake phase. The pollen in the silt is dominated by grasses and other NAP. A small transitional zone with coarse gyttja above the silt was radiocarbon dated at 8780 \u00B1 210 yrs B.P. The pollen diagram shows Betula and Hippoph\u00E4e maxima at the dated level. This date gives a minimum age for the drainage of the lake, and indicates that it existed for only a short period. Contrary to earlier suggestion, a valley fill of till and sediments at Skåbu was not able to maintain the lake after the deglaciation. In a 2.1 m-thick peat layer, above the gyttja, Pinus is the dominating pollen, indicating the presence of a dense pine forest. The Alnus Rise is radiocarbon dated 7870 \u00B1 80 yrs B.P.