Late Pleistocene glaciations in the Gissar Range, Tajikistan, based on 10Be surface exposure dating
Late Pleistocene glaciations in the Gissar Range, Tajikistan, based on 10Be surface exposure dating
复制标题
DOI：
10.1016/j.palaeo.2012.10.031
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
R. Zech;I. Röhringer;P. Sosin;Hamdam Kabgov;S. Merchel;S. Akhmadaliev;W. Zech
中科院分区：
文献类型：
--
作者：
R. Zech;I. Röhringer;P. Sosin;Hamdam Kabgov;S. Merchel;S. Akhmadaliev;W. Zech
山地冰川是气候变化的敏感指标，特别是夏季气温和降水。因此，中亚的冰川年代学被认为可以提供有关过去温度变化、降水和大气环流相关变化的宝贵信息。然而，可用的年龄控制仍然很少。在这里，我们根据 13 个 10Be 表面暴露年龄，提出了塔吉克斯坦吉萨尔山脉的冰川年代学。突出的冰碛叶记录了海洋同位素阶段 (MIS) 2 期间与全球末次盛冰期 (LGM) 同步的冰川进展。根据衰退阶段推断，在大约 20ka 时已经发生了快速而显着的消冰作用。一个更古老、范围更广的冰川作用可以追溯到 MIS 4，而最广泛的冰川作用的时间仍然是推测的。与附近更干旱的帕米尔高原和天山的冰川年表不同，MIS 3 和 MIS 5 冰碛可能记录了过去降水量增加的时期，而更潮湿的吉萨尔山脉的冰川主要记录了过去温度和夏季日照的变化。
Mountain glaciers are sensitive indicators for climate change, especially with regard to summer temperature and precipitation. Glacial chronologies from Central Asia have therefore been suggested to provide valuable information about past changes in temperature, as well as precipitation and related changes in atmospheric circulation. However, available age control is still sparse. Here we present a glacial chronology for the Gissar Range, Tajikistan, based on thirteen10Be surface exposure ages. Prominent moraine lobes document glacial advances in phase with the global Last Glacial Maximum (LGM) during Marine Isotope Stage (MIS) 2. Rapid and significant deglaciation occurred already at ~20ka as inferred from recessional stages. An older and slightly more extensive glaciation could be dated to MIS 4, whereas the timing of the most extensive glaciation remains speculative. In contrast to the glacial chronologies from the nearby, more arid Pamir and Tien Shan, where MIS 3 and MIS 5 moraines likely document past periods with increased precipitation, glaciers in the more humid Gissar Range predominantly recorded past changes in temperature and summer insolation.