Ice-free conditions in Novaya Zemlya 35000-30000cal years B.P., as indicated by radiocarbon ages and amino acid racemization evidence from marine molluscs

Jan Mangerud, Darrell Kaufman, Jesper Hansen, John Inge Svendsen

Research output: Contribution to journalArticle

25 Scopus citations

Abstract

Novaya Zemlya was covered by the eastern part of the Barents-Kara ice sheet during the glacial maximum of marine isotope stage 2 (MIS 2). We obtained 14C ages on 37 samples of mollusc shells from various sites on the islands. Most samples yielded ages in the range of 48-26 14C Ky. Such old samples are sensitive to contamination by young 14C, and therefore their reliability was assessed using replicate analyses and amino acid geochronology. The extent of aspartic acid racemization (AspD/L) indicates that many of the 14C ages are correct, whereas some are minimum ages only. The results indicate that a substantial part of Novaya Zemlya was ice-free about 35-27 14C Kya, and probably even earlier. Corresponding shorelines up to >140ma.s.l. indicate a large Barents-Kara ice sheet during early MIS 3. These results are consistent with findings from Svalbard and northern Russia: in both places a large MIS 4/3 Barents-Kara ice sheet is postulated to have retreated about 50Kya, followed by an ice-free interstadial that lasted until up to ca. 25Kya. The duration of the MIS 2 glaciation in Novaya Zemlya was calculated by applying the D/L values to a kinetic equation for Asp racemization. This indicates that the islands were ice covered for less than 3000 years if the basal temperature was 0°C, and for less than 10000 years if it was -5°C.

Original languageEnglish (US)
Pages (from-to)187-208
Number of pages22
JournalPolar Research
Volume27
Issue number2
DOIs
StatePublished - Aug 2008

Keywords

  • Amino acid racemization
  • Barents Sea ice sheet
  • Eurasian ice sheet
  • Last Glacial Maximum
  • marine molluscs

ASJC Scopus subject areas

  • Oceanography
  • Environmental Chemistry
  • Environmental Science(all)
  • Earth and Planetary Sciences (miscellaneous)

Fingerprint Dive into the research topics of 'Ice-free conditions in Novaya Zemlya 35000-30000cal years B.P., as indicated by radiocarbon ages and amino acid racemization evidence from marine molluscs'. Together they form a unique fingerprint.

  • Cite this