Megainterstadial Climate of the Salawusu Valley——Milanggouwan Stratigraphical Section
WEN Xiaohao1), LI Baosheng1, 2), David Dian ZHANG3), FAN Xiaoping1), YE Jianping1), DU Shuhuan1), GUO Yunhai4), CHEN Deniu5) 1) School of Geography, South China Normal University, Guangzhou, 5106312) State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 7100613) Department of Geography, the University of Hong Kong, Hong Kong4) School of Geographic and Biological Sciences, Guizhou Normal University, Guiyang, 5500015) Institute of Zoology, Chinese Academy of Sciences, Beijing, 100080
The fluctuating rhythms of the megainterstadial grain sizes and chemical elements for the Milanggouwan stratigraphical section is fairly coincident with the sedimentary cycles of the paleo-mobile dune sands alternate with fluvial-lacustrine facies/paleosols. The paleo-mobile dune sands are compared with modern mobile dune sands that are products of cold and dry climate dominated by the East Asian winter monsoon. The fluvial-lacustrine facies/paleosols' particles are finer, their geochemistry and weathering are strengthening, and especially they contain more mollusk fossils living in warm and wet environments, which indicate that they are controlled by the wet and warm climate of the East Asian summer monsoon. Hereby it seems that the megainterstadial climates of the Salawusu valley at least went through ten wet-warm events and nine cold-dry events and could be divided into five substages: MIS3e (58.85~48.98 ka BP), MIS3d (48.98~39.55 ka BP), MIS3c (39.55~34.59 ka BP), MIS3b (34.59~26.47 ka BP) and MIS3a (26.47~23.07 ka BP). Thereinto, nineteen cold/warm climatic fluctuations correspond with stadial/interstadial of GRIP, the five substages are rather consistent with the Guliya ice core in the climatic fluctuating features and phase as well as the North Atlantic climate reflected by the N. pachydema(s.) numbers of V23-81 core. The notable spectrums of the mean diameter are 21.70 ka, 1.05 ka, 0.64 ka and 0.50 ka, that is to say, the millennial-centennial climate is closely related with the relative growth and decline between the winter monsoon and the summer monsoon of East Asia controlled basically by the North Atlantic Deep-Sea Current, the ten millennial climate is closely linked to the Sun's radiation under the precession period.
【Fund】： 国家重点基础研究发展计划“973”项目(编号2004CB720206);; 中国科学院知识创新工程重要方向项目(编号KZCX2-SW-118);; 国家自然科学基金项目(编号49971009)资助成果
【CateGory Index】： P532
【CateGory Index】： P532