Marine Oxygen Isotope Stage(MIS)-6 Glacial Advances on the Tibetan Plateau More Extensive than during MIS-2 due to More Abundant Precipitation  

作　　者：Marie-Luce CHEVALIER WANG Shiguang Anne REPLUMAZ LI Haibing 

机构地区：[1]Key Laboratory of Deep-Earth Dynamics of Ministry of Natural Resources,Institute of Geology,CAGS,Beijing 100037,China [2]Jiangsu Donghai Crustal Activity in Deep Holes of the Continental Scientific Drilling National Observation and Research Station,Lianyungang,Jiangsu 222300,China [3]Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou),Guangzhou 511458,China [4]National Institute of Natural Hazards,MEMC,Beijing 100037,China [5]ISTerre,UniversitéGrenoble Alpes,CNRS,Grenoble 38610,France

出　　处：《Acta Geologica Sinica(English Edition)》2022年第5期1484-1494,共11页地质学报（英文版）

基　　金：financially supported by the Second Tibetan Plateau Scientific Expedition of the Ministry of Science and Technology of China(Grant No.2019QZKK0901);the National Natural Science Foundation of China(Grant Nos.42020104007,41941016);the China Geological Survey(Grant No.DD20221630)。

摘　　要：Numerous studies dated glacial deposits within the Himalayan-Tibetan orogen.While most focus on young deposits,i.e.,younger than the Last Glacial Maximum(LGM or Marine oxygen Isotope Stage(MIS)-2,~20 ka),older moraines such as those from MIS-6(~130–191 ka)are much harder to date and interpret due to the less well-preserved nature of their surfaces and boulders,as well as their scattered and continuous age distribution due to long-lived erosion since deposition.Here,we dated with~(10)Be,two imbricated moraines near Yadong in southern Tibet,as MIS-2 and 6,showing that the most extensive,smooth surfaces were abandoned during MIS-6.Compiling published data from 54 MIS-6 moraines on the Tibetan Plateau reveals that they exist in most regions,dry or humid.They are particularly well-preserved(sharp crests)in eastern and northern Tibet,while in southern and central Tibet,their crests are rounded to sub-rounded.Because both MIS-2 and 6 were equally cold,and because MIS-6 moraines are much more extensive than those from the LGM,we conclude that MIS-6 glacial advances were controlled by more abundant precipitation than during MIS-2.This would be consistent with the peak in Asian monsoon during MIS-6,revealed by sediments from the South China Sea.

关 键 词：Yadong rift southern Tibet cosmogenic isotopes Quaternary paleo-precipitation moraine morphology Indian monsoon 

分 类 号：P343.6[天文地球—水文科学] P736.44[天文地球—地球物理学]