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Northwest Siberia as a MIS 2 desert? Inferences from quartz morphoscopy and polygonal ice wedgesстатья
Информация о цитировании статьи получена из
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 23 января 2026 г.
- Авторы: Sheinkman V., Sharapov D., Sedov S.
- Журнал: Quaternary International
- Том: 620
- Номер: Volume 620, 20.
- Год издания: 2022
- Издательство: Pergamon Press Ltd.
- Местоположение издательства: United Kingdom
- Первая страница: 46
- Последняя страница: 57
- DOI: 10.1016/j.quaint.2021.06.007
- Аннотация: Following a major revision of the Sartan ice sheet limits, Velichko et al.’s (2011) view of northwestern Siberia asa cold arid desert during MIS 2 (27.8–11.7 ka) has been prominent in regional scholarship. Our article presentsthe analysis of a series of sandy sediments associated with MIS 2 polygonal ice-wedge pseudomorphs (PIWPs)located in the Lower Nadym, the Middle Nadym, and the Siberian Uvals regions. Whereas Velichko et al.’s colddesert hypothesis was based on optical morphoscopy, our research relied on the scanning electron microscopetechnology (in conjunction with sedimentological, soils, and radiocarbon data). Our morphoscopic analysis ofthree wedge fill – host sediment pairs suggests that none of the MIS 2 surface sediments can be unequivocallyassociated with desert dune environments, but instead resemble alluvial deposits that have been moderately tosubstantially reworked by aeolian and cryogenic (freeze-thaw) processes. While the environmental characteristicsvaried between different sub-regions, northwestern Siberia likely resembled a sparsely vegetated tundraduring MIS 2. AMS radiocarbon dates obtained from the organic matter of paleosols discovered inside of PIWPsindicate that the climate warming in northwestern Siberia began around 13.5–13 ka cal BP (end of MIS 2). Thisclimatic shift was associated with a more pronounced warm season, as evidenced by the surface sedimentsexperiencing more intensified freeze-thaw cycles in all of the examined locations. Judging from our analysis ofsandy deposits, aeolian activity intensified in the Siberian Uvals in the middle MIS 2, compared to early MIS 2.Aeolian activity also intensified in the Middle Nadym in the second part of MIS 2, compared to the first part ofMIS 2. Besides the intensified freeze-thaw processes at the end of MIS 2, surface deposits of the Lower Nadymregion remained relatively stable throughout the Sartan cryochron.
- Добавил в систему: Шейнкман Владимир Семенович