Distribution and timing of Holocene and late Pleistocene glacier fluctuations in western Mongolia
Zeitschrift: Annals of Glaciology, 201657, 71: 169 - 178
DOI: https://doi.org/10.3189/2016AoG71A030
Persistent URL: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/7006
Persistent URL: http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/7006
Lehmkuhl, Frank; Klinge, Michael; Rother, Henrik; Hülle, Daniela, 2016: Distribution and timing of Holocene and late Pleistocene glacier fluctuations in western Mongolia. In: Annals of Glaciology, Band 57, 71: 169 - 178, DOI: 10.3189/2016AoG71A030.
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Despite being a key location for paleoglaciological research in north-central Asia, with the
largest number of modern and Pleistocene glaciers, and in the transition zone between the humid
Russian Altai and dry Gobi Altai, little is known about the precise extent and timing of Holocene and
late Pleistocene glaciations in western Mongolia. Here we present detailed information on the
distribution of modern and late Holocene glaciers, and new results addressing the geomorphological
differentiation and numerical dating (by optically stimulated luminescence, OSL) of Pleistocene glacial
sequences in these areas. For the Mongolian Altai, geochronological results suggest large ice advances
correlative to marine isotope stages (MIS) 4 and 2. This is in contrast to results from the Khangai
mountains, central Mongolia, showing that significant ice advances additionally occurred during MIS3.
During the Pleistocene, glacial equilibrium-line altitudes (ELAs) were �500 to >1000m lower in the
more humid portion of the Russian and western Mongolian Altai, compared to 300–600m in the drier
ranges of the eastern Mongolian Altai. Pleistocene ELAs in the Khangai mountains were depressed by
700–1000 m, suggesting more humid conditions at times of major glaciation than in the eastern
Mongolian Altai. This paleo-ELA pattern reveals that the precipitation gradient from the drier to the
more humid regions was more pronounced during glacial times than at present.
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- Geologie [930]