Sediment, ground ice and micropaleontological data from the pingo exposure 'Shirokovsky Kholm' (Kolyma Lowland, NE Siberia) sampled in 2012, supplement to: Wetterich, Sebastian; Schirrmeister, Lutz; Nazarova, Larisa B; Palagushkina, Olga V; Bobrov, Anatoly A; Pogosyan, Lilith; Savelieva, Larissa A; Syrykh, Ludmila S; Matthes, Heidrun; Fritz, Michael; Günther, Frank; Opel, Thomas; Meyer, Hanno (2018): Holocene thermokarst and pingo development in the Kolyma Lowland (NE Siberia). Permafrost and Periglacial Processes, 29(3), 182-198

Ground ice and sedimentary records of a pingo exposure reveal insights into Holocene permafrost, landscape and climate dynamics. Early to mid‐Holocene thermokarst lake deposits contain rich floral and faunal paleoassemblages, which indicate lake shrinkage and decreasing summer temperatures (chironom...

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Bibliographic Details
Main Authors: Wetterich, Sebastian, Meyer, Hanno, Nazarova, Larisa B, Palagushkina, Olga V, Savelieva, Larissa A, Schirrmeister, Lutz, Syrykh, Ludmila S
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA - Data Publisher for Earth & Environmental Science 2017
Subjects:
Ice
Online Access:https://dx.doi.org/10.1594/pangaea.884369
https://doi.pangaea.de/10.1594/PANGAEA.884369
Description
Summary:Ground ice and sedimentary records of a pingo exposure reveal insights into Holocene permafrost, landscape and climate dynamics. Early to mid‐Holocene thermokarst lake deposits contain rich floral and faunal paleoassemblages, which indicate lake shrinkage and decreasing summer temperatures (chironomid‐based TJuly) from 10.5 to 3.5 cal kyr BP with the warmest period between 10.5 and 8 cal kyr BP. Talik refreezing and pingo growth started about 3.5 cal kyr BP after disappearance of the lake. The isotopic composition of the pingo ice (δ18O − 17.1 ± 0.6‰, δD −144.5 ± 3.4‰, slope 5.85, deuterium excess −7.7± 1.5‰) point to the initial stage of closed‐system freezing captured in the record. A differing isotopic composition within the massive ice body was found (δ18O − 21.3 ± 1.4‰, δD −165 ± 11.5‰, slope 8.13, deuterium excess 4.9± 3.2‰), probably related to the infill of dilation cracks by surface water with quasi‐meteoric signature. Currently inactive syngenetic ice wedges formed in the thermokarst basin after lake drainage. The pingo preserves traces of permafrost response to climate variations in terms of ground‐ice degradation (thermokarst) during the early and mid‐Holocene, and aggradation (wedge‐ice and pingo‐ice growth) during the late Holocene.