Formation age and development characteristics of rock glaciers in the Zheduo Mountain,the southeastern Qinghai-Xizang Plateau
Understanding the evolution history of rock glaciers is the key to reveal the response of periglacial en-vironment to climate change.However,the chronology of rock glaciers is relatively inadequate due to the lack of suitable dating materials and other reasons.Quaternary glaciation and periglacial environment were widely de-veloped in Zheduo Mountain,located on the southeastern margin of the Qinghai-Xizang Plateau,which provid-ed conducive conditions for the formation of rock glaciers.Based on the geomorphological investigation and 10 Be exposure dating,we accurately dated a moraine-type rock glacier in Zheduo Mountain and further discussed its formation age and development characteristics.The results show a formation time of rock glaciers in the Zheduo Mountain at about(11.8±0.3)ka,corresponding to the late period of the Last Deglaciation.Millennium-scale climatic cooling events during the Last Deglaciation led to multiple cold and warm climate changes,leading to repeated glacier advances and retreats.The transport and accumulation of a large number of moraines strongly shaped the geomorphic landscape,promoted the continuous expansion of permafrost scale,and also provided the material basis for rock glaciers.Based on the studies of stone glaciers in the Qinghai-Xizang Plateau and oth-er parts of the Northern Hemisphere,it is found that the formation age and evolution characteristics of the rock glaciers during the Last Deglaciation are similar.During the large-scale retreats of the glacier,sudden cooling events lead to the glacier advance and the expansion of the periglacial area,and when the temperature rises,the deglaciated proglacial area becomes a new periglacial environment,and glacial meltwater and sediment are gen-erated at the same time,which promotes the development of the rock glaciers.The glacial and periglacial geo-morphological processes,such as the repeated advance and retreat of glaciers,the expansion of permafrost ar-eas,and the development of rock glaciers,caused by climate change,to a certain extent,indicate that the inter-action of glacial and periglacial geomorphological processes in the interglacial cycle is the key to understand the response of the cryosphere to climate change.
rock glaciersZheduo Mountainformation agedevelopment characteristicsclimate change
万方数据
维普
