Millennial climate changes since MIS 3 revealed by element records in deep-sea sediments from northern South China Sea  

作　　者：Xin Xie Hong-Bo Zheng Pei-Jun Qiao 

机构地区：[1]State Key Laboratory of Marine Geology, Tongji University [2]School of Geography Science, Nanjing Normal University

出　　处：《Chinese Science Bulletin》2014年第8期776-784,共9页

基　　金：supported by the National Natural Science Foundation of China(40806021,40830107,and 91128208);the National Basic Research Program of China(2007CB815906)

摘　　要：High resolution elemental records in core MD05-2903 from the northern South China Sea were obtained from XRF scanning and grain size and mineral component analyses.The K/Ti curve reveals climate changes since MIS 3 on a millennial scale,representing one of the best such records so far from deep-sea sediments of the South China Sea.When compared our K/Ti record with other climate records from high latitude ice cores and from East Asia stalagmites,variations in the K/Ti record show some typical saw-shaped features of rapid climate changes in the Northern Hemisphere.Grain size analysis reveals a close relationship between variations in K/Ti and in the fine end-member grain size.XRD analysis confirms that high K/Ti layers were dominated by K-rich weathering minerals,especially illite,while low K/Ti layers contain low illite but high abundance of Ti-rich heavy minerals.Therefore,the K/Ti record reflects changes in the input and deposition of fine weathering minerals and heavy minerals in the northern South China Sea region during stadials and interstadials.These elemental changes were largely controlled by variations in rainfall,erosion,and fluvial transportation induced by East Asia Monsoon.High resolution elemental MD05-2903 from the northern South records in core China Sea were obtained from XRF scanning and grain size and mineral component analyses. The K/Ti curve reveals climate changes since MIS 3 on a millennial scale, representing one of the best such records so far from deep-sea sediments of the South China Sea. When compared our K/Ti record with other climate records from high latitude ice cores and from East Asia stalagmites, variations in the K/Ti record show some typical saw-shaped features of rapid climate changes in the Northern Hemisphere. Grain size analysis reveals a close relationship between variations in K/Ti and in the fine end-member grain size. XRD analysis confirms that high K/Ti layers were dominated by K-rich weathering minerals, especially illite, while low K/Ti layers contain low illite but high abundance of Ti-rich heavy minerals. Therefore, the K/Ti record reflects changes in the input and deposition of fine weathering minerals and heavy minerals in the northern South China Sea region during stadials and interstadials. These elemental changes were largely con- trolled by variations in rainfall, erosion, and fluvial trans- portation induced by East Asia Monsoon.

关 键 词：深海沉积物 中国南海 气候变化 MIS 元素 显示 X射线衍射分析 矿物风化 

分 类 号：P736.2[天文地球—海洋地质]