Timing of glacier expansion during the Last Glacial in the inner Tien Shan, Kyrgyz Republic by OSL dating
Timing of glacier expansion during the Last Glacial in the inner Tien Shan, Kyrgyz Republic by OSL dating
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DOI：
10.1016/j.quaint.2008.04.010
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发表时间：
2009-04
影响因子：
2.2
通讯作者：
C. Narama;R. Kondo;S. Tsukamoto;T. Kajiura;M. Duishonakunov;K. Abdrakhmatov
中科院分区：
文献类型：
--
作者：
C. Narama;R. Kondo;S. Tsukamoto;T. Kajiura;M. Duishonakunov;K. Abdrakhmatov
光释光（OSL）测年应用于冰川沉积物和邻近的黄土冰碛在Terskey Ala-Too和At-Bashy范围内天山，吉尔吉斯共和国（吉尔吉斯斯坦）。在这两个研究区域观测到了末次冰期的两次大规模冰川扩张; Teskey（=Terskey）第一和第二阶段的冰碛物的年代为海洋同位素阶段（MIS）4-早期MIS 3和MIS 2，而在At-Bashy山脉的At-Bashy第二阶段的年代为晚期MIS 3-MIS 2。末次冰期两次扩张的时间与全球寒冷时期和北方主要冰盖的前进相吻合。然而，在Teskey Ala-Too山脉的MIS 4-MIS 3早期发生了更大的扩张，这表明MIS 4-MIS 3早期的气候比MIS 2更潮湿。这可能是由于MIS 2期间西伯利亚高压的加强限制了西风带的影响，从而减少了研究区的降水。
Optically stimulated luminescence (OSL) dating was applied to glacial sediments and adjacent loess from moraines in the Terskey Ala-Too and At-Bashy Ranges in the inner Tien Shan, Kyrgyz Republic (Kyrgyzstan). Two large glacier expansions during the Last Glacial were observed in the two study areas; Teskey (=Terskey) Stages I and II moraines were dated to marine isotope stage (MIS) 4–early-MIS 3 and MIS 2, and At-Bashy Stage II in the At-Bashy Range dated to late-MIS 3–MIS 2. The timing of the two expansions during the Last Glacial coincided with global cold periods and with advances of the major Northern Hemisphere ice sheets. However, the fact that the greater expansion occurred in MIS 4–early-MIS 3 in the Teskey Ala-Too Range, suggests that climate during MIS 4–early-MIS 3 was more humid than during MIS 2. It is possible that the strengthened Siberian High during MIS 2 restricted the impact of the westerlies and this reduced precipitation in the study area.