Helena Alexandersson

Helena Alexanderson

Professor

Helena Alexandersson

Depositional history of the North Taymyr ice-marginal zone, Siberia - a landsystem approach

Författare

  • Helena Alexanderson
  • Lena Adrielsson
  • Christian Hjort
  • Per Möller
  • O Antonov
  • S Eriksson
  • M Pavlov

Summary, in English

The sediment-landform associations of the northern Taymyr Peninsula in Arctic Siberia tell a tale of ice sheets advancing from the Kara Sea shelf and inundating the peninsula, probably three times during the Weichselian. In each case the ice sheet had a margin frozen to its bed and an interior moving over a deforming bed. The North Taymyr ice-marginal zone (NTZ) comprises ice-marginal and supraglacial landsystems dominated by thrust-block moraines 2-3 km wide and large-scale deformation of sediments and ice. Large areas are still underlain by remnant glacier ice and a supraglacial landscape with numerous ice-walled lakes and kames is forming even today. The proglacial landsystem is characterised by subaqueous (e.g. deltas) or terrestrial (e.g. sandar) environments, depending on location/altitude and time of formation. Dating results (OSL, C-14) indicate that the NTZ was initiated ca. 80 kyr BP during the retreat of the Early Weichselian ice sheet and that it records the maximum limit of a Middle Weichselian glaciation (ca. 65 kyr BP). During both these events, proglacial lakes were dammed by the ice sheets. Part of the NTZ was occupied by a thin Late Weichselian ice sheet (20-12 kyr BP), resulting in subaerial proglacial drainage. Copyright (C) 2002 John Wiley Sons, Ltd.

Ämne

  • Geology

Nyckelord

  • glaciation
  • ice-marginal zone
  • landsystem
  • Weichselian
  • Siberia

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 1099-1417