Glaciotectonised Quaternary sediments at Cape Shpindler, Yugorski Peninsula, Arctic Russia: implications for glacial history, ice movements and Kara Sea Ice Sheet configuration

Abstract

The coastal cliffs of Cape Shpindler, Yugorski Peninsula, Arctic Russia, occupy a key position for recording overriding ice sheets during past glaciations in the Kara Sea area, either from the Kara Sea shelf or the uplands of Yugorski Peninsula/Polar Urals. This study on Late Quaternary glacial stratigraphy and glaciotectonic structures of the Cape Shpindler coastal cliffs records two glacier advances and two ice-free periods older than the Holocene. During interglacial conditions, a sequence of marine to fluvial sediments was deposited. This was followed by a glacial event when ice moved southwards from an ice-divide over Novaya Zemlya and overrode and disturbed the interglacial sediments. After a second period of fluvial deposition, under interstadial or interglacial conditions, the area was again subject to glacial overriding, with the ice moving northwards from an inland ice divide. The age-control suggests that the older glacial event could possibly belong to marine oxygen isotope stage (MOIS) 8, Drenthe (300-250 ka), and that the underlying interglacial sediments might be Holsteinian (>300 ka). One implication of this is that relict glacier ice, buried in sediments and incorporated into the permafrost, may survive several interglacial and interstadial events. The younger glacial event recognised in the Cape Shpindler sequence is interpreted to be of Early-to-Middle Weichselian age. It is suggested to correlate to a regional glaciation around 90 or 60 ka. The Cape Shpindler record suggests more complex glacial dynamics during that glaciation than can be explained by a concentric ice sheet located in the Kara Sea, as suggested by recent geological and model studies.

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

“…Structural and textural evidence from tills and sub-till sediments in our Severnaya Zemlya stratigraphy imply deformation and deposition during expansion of local ice caps, with no evidence other than the raised beaches for expansion of thick Kara Sea-based ice sheets onto southern October Revolution Island. These observations suggest that initial KSIS growth occurred with formation of local ice caps, consistent with data from, e.g., the Taymyr Peninsula (Hjort et al, 2003;Mo¨ller et al, in prep), the Yugorski Peninsula (Lokrantz et al, 2003) and the western Yamal Peninsula (Forman et al, , 2002. These local icecaps were characterized by wet-based thermal regimes, as suggested from basal tills and sub-till plastic deformational structures on Severnaya Zemlya.…”

Sedimentary imprints of former ice-sheet margins: Insights from an end-Ordovician archive (SW Libya)

“…Syntectonic deposits demonstrate that the ice front advanced and then probably stabilised over its own deformed proglacial depositional wedge. The lack of convolute bedding is striking and may suggest that the glaciotectonic deformation affected either frozen (see below the Section 6.5; Lokrantz et al, 2003) or dry sediments. Owing to the presence of the frozen sandstone intraclasts (see Section 4.3.1) and of the presence of clastic dykes indicating overpressures (see Section 4.2.1) in deformed sand-dominated (i.e., normally porous) deltaic deposits, the frozen sediment hypothesis is more plausible (see Section 6.5).…”

Glacial and palaeoenvironmental history of the Cape Chelyuskin area, Arctic Russia

“…Such expansions of local ice caps are also suggested by, e.g., Forman et al. (1999, 2002), Lokrantz et al. (2003) and Hjort & Funder (2008).…”

“…Complicating things further is the fact that studies in Severnaya Zemlya (Möller et al. 2006), the western Taymyr Peninsula (Hjort & Funder 2008[this issue]), the Yugorski Peninsula (Lokrantz et al. 2003) and the western Yamal Peninsula (Forman et al.…”