Variation of Zr/Rb ratios on the Loess Plateau of Central China during the last 130000 years and its implications for winter monsoon

作     者：LIU Lianwen CHEN Jun CHEN Yang JI Junfeng LU Huayu 

作者机构：Institute of Surficial GeochemistryState Key Laboratory of Mineral Deposit ResearchDepartment of Earth SciencesNanjing UniversityNanjing 210093China Institute of Earth EnvironmentChinese Academy of Sciences 

出 版 物：《Chinese Science Bulletin》 (CHINESE SCIENCE BULLETIN)

年 卷 期：2002年第47卷第15期

页      面：1298-1302页

核心收录：

学科分类：070903[理学-古生物学与地层学(含：古人类学)] 0709[理学-地质学] 07[理学] 

基　　金：This work was supported by the National Key Basic Research Project (Grant No. G1999043400) the National Natural Science Foundation of China (Grant No. 40173003) 

主　　题：loess index of winter monsoon Zr/Rb ratios grain size. 

摘      要：To find a new index of winter monsoon without effects of chemical weathering and pedogenesis is an important task in loess research. Chemical analysis of five grain size fractions (i.e. 32μm, 32-20μm, 20-8μm, 8-2μm and 2μm) show that Zr is enriched in coarser grain size, while Rb is concentrated in finer fractions. An excellent correlation occurs between Zr/Rb ratios and mean grain size in loess units (L1LL1 and L1LL2) from Huanxian and Xifeng sections, reflecting that Zr/Rb ratios increase when grain size is coarser. Due to immobility of the two elements during the postdepositional process, Zr/Rb ratios can eliminate the effect of weathering and pedogenesis and serve as an excellent proxy on winter monsoon variation. The Zr/Rb ratio curves of the Huanxian, Xifeng and Luochuan sections during the last 130000 years show that the winter monsoon strength was very weak during MIS 3, which corresponded to the intensity during MIS 5.