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

Abstract

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, 14 C) 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.

Severnaya Zemlya, Arctic Russia: a nucleation area for Kara Sea ice sheets during the Middle to Late Quaternary

“…Mo¨ller et al (1999a) and Alexanderson et al (2002) concluded that northern Taymyr were subjected to extensive glaciations in Early to Middle Weichselian times (ca 90-80 and 70-60 ka BP; MIS 5 and 4), but evidence of older glaciations is sparse. Evidence of multiple pre-LGM glaciations is also present on Severnaya Zemlya (Bolshiyanov and Makeyev, 1995).…”

“…The KSIS recession halted temporarily north of the Byrranga Mountains and constructed the complex North Taymyr ice-marginal Zone (NTZ, Fig. 25B) (Alexanderson et al, 2001(Alexanderson et al, , 2002. Simultaneously an ice-dammed lake was formed between the ice margin and the Byrranga Mountains with meltwater rerouting southwards along the Taymyr River valley, all dated by OSL ages of ca 80 ka BP .…”

“…On the northern flank the KSIS seems to have expanded to the continental shelf margin also in the Early Weichselian, as indicated by IRD peaks in sediment cores retrieved off the shelf, interpreted to represent advance/retreat phases of the KSIS (Knies et al, 2001). The Kara Sea ice sheet re-advanced southwards to the NTZ at around 70-54 ka BP according to OSL ages (Alexanderson et al, 2001(Alexanderson et al, , 2002, i.e. in the Middle Weichselian (Fig.…”

Luminescence chronology of non‐glacial sediments in Changeable Lake, Russian High Arctic, and implications for limited Eurasian ice‐sheet extent during the LGM

“…Based on geomorphological field work, analyses of aerial photographs and geochronological data, Alexanderson et al (2001Alexanderson et al ( , 2002 argue that LGM ice was present on the northern Taymyr Peninsula (central arctic Siberia). Attempts are being made to trace the LGM boundary east toward the Taymyr Peninsula by use of marine geophysical and geological studies (e.g.…”

Discoveries of woolly mammoth, Mammuthus primigenius (Proboscidea: Elephantidae) and some other Pleistocene mammals on the Taimyr Peninsula.

“…Based on geological data Möller et al (1999) and Niessen et al (1999) found no evidence for extended glaciation during the last glacial maximum. Only the northern and northwestern coastal lowlands were covered with a thin ice cap (Alexanderson et al, 2002). Dryness prevented the formation of large ice sheets (Svendsen et al, 1999).…”