沙漠/黄土过渡带杨桥畔全新世地层微量元素特征及其所揭示的古气候变化  

Geochemical Characteristics of Trace Elements in the Yangqiaopan Section of the Desert-Loess Transitional Zone during the Holocene and Its Implication in the Paleoclimatic Change

作　　者：吴利杰[1] 石建省[1] 郭娇[1] 王成敏[1] 毕志伟[1] 董秋瑶[1] 陈洪云[1] 

机构地区：[1]中国地质科学院水文地质环境地质研究所,石家庄050061

出　　处：《矿物岩石地球化学通报》2015年第2期323-329,共7页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：中国地质科学院水文地质环境地质研究所基本科研业务费项目(SK201403)

摘　　要：通过对沙漠-黄土过渡带杨桥畔全新世地层中20种微量元素的地球化学特征分析,结合年代学资料,探讨了该地区13.0ka B.P.以来的气候环境变化过程。研究表明,微量元素地层分布规律明显,化学成分具有很高地一致性,Cr、Cs、Co、Cu、Mn与I可作为衡量东亚夏季风强度的古气候替代性指标。根据主要微量元素演替所揭示的古气候变化特征,将该地区气候变化可划分为5个阶段：13.0-11.7ka B.P.气候干燥寒冷;11.7-10.0ka B.P.气候略温偏干;10.0-6.4ka B.P.气候温暖湿润;6.4-1.60ka B.P.偏冷干气候恶化期;1.6ka B.P.以来气候继续朝冷干方向发展,并且冷暖干湿交替频繁。通过与黄土、石笋等记录变化对比,发现杨桥畔地区全新世气候演化过程与全球气候环境的变化基本一致。On the basis of geochemical characteristics of 20 kinds of trace elements in the Yangqiaopan section of the desert-loess transitional zone, chronology, and literature researches, we discussed climate changes in the Yangqiaoban area since 13.0 ka B.P. and came to the following conclusions： the strata distribution of trace elements with high consistency composition in the Yangqiaopan section was obvious; Cr, Cs, Co, Cu, Mn, and I can be used as paleoclimate proxies for the strength change of the East Asian summer monsoon. The climate change revealed by the characteristics of main trace elements could be divided into five stages ： the climate was very dry and cold during 13.0- 11.7ka B.P. ; the climate was slightly warm and dry during 11.7 - 10.0 ka B.P. ; the climate was mild and wet during 10.0 - 6.4 ka B.P. ; the climate became slightly cold and dry again during 6.4 - 1.60 ka B.P. ; the climate was then cold and dry since 1.60 ka B.P., and the cold/warm climates alternated frequently.

关 键 词：地球化学 东亚季风 磁化率 风化成壤作用 毛乌素沙地 

分 类 号：P532[天文地球—古生物学与地层学] P595[天文地球—地质学]