Isotopic composition of syngenetic ice wedges and palaeoclimatic reconstruction, western Taymyr, Russian Arctic

• Published in: Permafrost and Periglacial Processes
• Main Authors: Irina Streletskaya, Alexander Vasiliev, Hanno Meyer
• Format: Article in Journal/Newspaper
• Language: unknown
• Subjects: Arctic; Taymyr; Yenisey; Dikson; Karga
• Online Access: https://doi.org/10.1002/ppp.707

Recent, Holocene and Late Weichselian (Sartan) generations of syngenetic ice wedges developed in loess‐like and alluvial sediments were investigated along the coast of the Yenisey Bay from Sopochnaya Karga Cape (71°88'N, 82°68'E) to Dikson (73°31'N, 80°34'E). Ages of about 3.4 − 4.6 ka BP were determined for peat layer and wood fragments in ice‐rich deposits surrounding ice wedges near Dikson. The isotopic composition of these wedges reflects relatively cold winter temperatures in the Holocene. The lightest isotope composition characterises older ice wedges near Dikson and Sopochnaya Karga Cape. A warming trend between ice wedges of different generations was indicated by a distinct increase in O (4 − 5 ‰) and H (35 − 40‰) stable isotopes. Palaeotemperature reconstruction based on the data shows that winter temperatures during the formation of older generation ice wedges were lower than Holocene winter temperatures, indicating that they developed in the Late Weichselian (MIS2). The presence of syngenetic ice wedges strongly suggests that the coast of western Taymyr was not ice‐covered at this time. Copyright © 2011 John Wiley & Sons, Ltd.