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Keywords:

  • syngenetic ice wedges;
  • radiocarbon dating;
  • stable isotopes;
  • southern limit of permafrost;
  • yedoma;
  • Dansgaard-Oeschger events

ABSTRACT

The monograph summarises radiocarbon and stable isotope research on syngenetic ice wedges. The southern boundary of active and inactive ice wedges in Russian permafrost is re-evaluated and revised. A new model of cyclical growth of syngenetic ice wedges is proposed, involving three cycles in ice-wedge development: micro-, meso- and macrocycles. Direct dating of syngenetic ice wedges can be carried out by accelerator mass spectrometry (AMS) radiocarbon dating of organic microinclusions and pollen concentrates from ice-wedge ice. Dating reveals vertical and lateral variation in the age of yedoma at Duvanny Yar (NE Yakutia), one of the key syngenetic permafrost exposures in Eurasia. Radiocarbon ages and oxygen and deuterium isotopic values of syngenetic ice wedges in northern Russia and North America provide insights into palaeoenvironmental history and palaeogeocryology. Syngenetic ice wedges sometimes show complex cryostratigraphic relationships with other types of ice, including massive ice, icing ice and pingo ice. Comparison of isotope records from syngenetic ice wedges with those from Greenland ice cores reveals evidence for Dansgaard-Oeschger (D/O) events preserved in Siberian permafrost. Copyright © 2013 John Wiley & Sons, Ltd.