MIS 3时期青藏高原东南部稻城古冰帽冰进事件研究

MIS 3 glacial advance of the paleo-Daocheng Ice Cap,southestern Qinghai-Tibet Plateau

深海氧同位素3阶段(Marine Isotope Stage 3,MIS 3)是全球气候演化过程中特殊的时期,对深入认识区域古气候、古环境演变具有重要意义。青藏高原东南部稻城古冰帽是第四纪冰川作用历史和古气候研究的理想区域,许多学者在该区进行了冰川地貌学和年代学研究。目前,该区域在MIS 3阶段是否存在冰川前进事件仍存在争论。现着重从洞穴石笋、高原冰芯、海洋沉积、古湖孢粉等记录来总结我国MIS 3阶段的气候环境状况,并搜集高原及周边地区MIS 3阶段冰进事件的记录,结合稻城古冰帽区已发表的MIS 3阶段的年代数据来探讨稻城古冰帽区MIS 3阶段的冰川前进的可能性。结果表明:稻城古冰帽区MIS 3阶段(43~53 ka)发生了大规模冰进事件,这可能是由于该冰帽区处于相对冷湿环境且受到了西南季风的影响。本研究可为区域气候重建与环境演变提供新的依据。

The MIS 3 （Marine Isotope Stage 3 ） was a special period during the past global climate evolution process. It is important for getting more details about MIS 3 for deeply understanding the regional change of paleo-climate and paleo-environment. The paleo-Daocheng Ice Cap is situated in the southeastern Tibetan Plateau, where the glacial remnants （ including the oldest moraines in the Hengduan Mountains） have been well preserved, which provides a natural laboratory to study the glacial history and climate change during Quaternary. Although there has been a lot of work in this area, consensus has not reached on the time of the maximum glaciation and whether glacier advance during MIS 3. In this paper, the possibility of MIS 3 glacial advance in paleo- Daocheng Ice Cap is explored based on the climatic records （ stalagmites, ice cores, marine sediments and pollen data） and the dating data of glacial advance in the plateau （include the paleo-Daocheng Ice Cap） and around areas during MIS 3. The results showed that glaciers had advanced during 43 -53 ka （MIS 3 ）. This research will provide new data for climate and environment reconstruction.