Cirque glacier activity in arctic Norway during the last deglaciation

Numerous cirques of the Lofoten-Vesteralen archipelago in northern Norway have distinct moraine sequences that previously have been assigned to the Allerod-Younger Dryas (similar to 13,400 to 11,700 yr BP) interval, constraining the regional distribution of the equilibrium-line altitude (ELA) of cirque and valley glaciers. Here we present evidence from a once glacier-fed lake on southern Andoya that contests this view. Analyses of radiocarbon dated lacustrine sediments including rock magnetic parameters, grain size, organic matter, dry bulk density and visual interpretation suggest that no glacier was present in the low-lying cirque during the Younger Dryas-Allerod. The initiation of the glacial retreat commenced with the onset of the Bolling warming (similar to 14,700 yr BP) and was completed by the onset of Allerod Interstade (similar to 13,400 yr BP). The reconstructed glacier stages of the investigated cirque coincide with a cool and dry period from similar to 17,500 to 14,700 yr BP and a somewhat larger Last Glacial Maximum (LGM) advance possibly occurring between similar to 21,050 and 19,100 yr Bp. (c) 2007 University of Washington. All rights reserved.