Paleoglaciation of Shaluli Shan, southeastern Tibetan Plateau
Paleoglaciation of Shaluli Shan, southeastern Tibetan Plateau
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DOI：
10.1016/j.quascirev.2012.12.009
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发表时间：
2013-03
影响因子：
4
通讯作者：
P. Fu;A. Stroeven;J. Harbor;C. Hättestrand;J. Heyman;M. Caffee;Liping Zhou
中科院分区：
文献类型：
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作者：
P. Fu;A. Stroeven;J. Harbor;C. Hättestrand;J. Heyman;M. Caffee;Liping Zhou
重建青藏高原的古冰川作用对于理解区域气候变化和全球气候变化之间的联系至关重要，在这里，我们关注的是青藏高原东南部沙鲁里山的冰川历史，该地区的大部分降水来自季风流。通过野外考察、地貌填图和冰碛物~（10）Be暴露年龄测定，确定了晚冰期冰川沉积物的最小年龄为13.0 ± 1.2 ~ 17.1 ± 1.6ka，全球末次盛冰期（gLGM）为21.6 ± 2.0ka，前末次盛冰期（pre-gLGM）为102.3 ± 10.0-183.6 ± 17.0ka。这些年龄是一致的，并显着扩展了已知的范围，从大多数以前的年代学工作，在这方面使用陆地宇宙成因核素，并包括一组日期的库照日冰碛提出了问题，以前的年表的基础上，电子自旋共振技术。在全球末次盛冰期，海子山高原和新龙高原覆盖了约4000 km 2的冰帽，大型冰川向下游延伸。冰帽冰川的存在，在这里，形成强烈对比的冰川在沙鲁里山和青藏高原更中心的地区，冰的扩张仍然局限于山谷。这一研究结果为揭示青藏高原古气候格局和季风演化提供了重要信息，并表明沙鲁里山冰川年代学与北方古冰盖的一致性高于青藏高原其他地区。
Reconstructing the paleoglaciation of the Tibetan Plateau is critical to understanding linkages between regional climate changes and global climate changes, and here we focus on the glacial history of the Shaluli Shan, an area of the southeastern Tibetan Plateau that receives much of its precipitation from monsoon flow. Based on field investigation, geomorphological mapping, and10Be exposure dating of moraines, we identify glacial deposits from the Late Glacial, with minimum ages at 13.0 ± 1.2 –17.1 ± 1.6 ka, global Last Glacial Maximum (gLGM) at 21.6 ± 2.0 ka, and pre-gLGM at 102.3 ± 10.0–183.6 ± 17.0 ka. These ages are consistent with and significantly extend the known range from most prior chronological work using terrestrial cosmogenic nuclides in this area, and include a set of dates for the Kuzhaori moraine that raise questions about prior chronologies based on the electron spin resonance technique. Ice caps about 4000 km2in size covered the Haizishan Plateau and the Xinlong Plateau during the global LGM, with large glaciers extending far down outlet valleys. The presence of ice cap glaciation, here, contrasts strongly to glaciation elsewhere in the Shaluli Shan and more central regions of the Tibetan Plateau where ice expansion remained constricted to valleys. This work provides important insights into the paleoclimate pattern and monsoon evolution of the Tibetan Plateau over past glacial cycles and indicates that the Shaluli Shan has a glacial chronology more consistent with the Northern Hemisphere paleo-ice sheets than other areas of the Tibetan Plateau.