The Weichselian Glacial History of West Melrakkaslétta, Northeastern Iceland

Abstract

Melrakkaslétta is part of the volcanic zone in Northeastern Iceland and in the area subglacial mountains, lava fields, faults and fissures are evidence of recent volcanic activity. On West Melrakkaslétta glacial striae and deglaciation landforms have been correlated with Weichselian sediments that have been divided into 13 different stratigraphical units. The oldest sediments show that an oscillating glacier overrode marine sediments of Eemian or Weichselian age. Finally the glacier retreated and at least northwest Melrakkaslétta became ice free. A lava flow represents this Weichselian interstadial in the stratigraphy. The intermediate sediments show that the glacier advanced, then retreated to a floating stagnating glacier and advanced once more. The youngest sediments show that a marine environment was transformed into a glaciomarine one as a floating glacier advanced at a rising sea level at 12,700 B.P. The environment developed into marine at 12,100 B.P. and deglaciation and isostatic recovery set in. Ice-rafted debris show that this coincided with major deglaciation around the North Atlantic Ocean. During the Younger Dryas the northernmost part of the Icelandic inland ice sheet constituted a glacial dome over Melrakkaslétta. The final deglaciation and formation of marine limit is dated to 10,200 B.P.