高校地质学报2018，Vol.24Issue(2)：246-250,5.DOI:10.16108/j.issn1006-7493.2017115
中国东部主要黄土分布区的Sr-Nd同位素物源示踪研究
Provenances of the Major Loess Deposits in Eastern China Based on Sr and Nd Isotopic Characteristics
摘要
Abstract
The provenance study of the major loess deposits in eastern China can help understand the evolution since the late Quaternary in this area.Nd and Sr isotopes are the most commonly used source tracers for atmospheric dusts.This work applies the Sr-Nd isotope to trace the source of classical loess deposits in eastern China, including the Shandong Peninsula and its adjacent coastal area,the loess deposits along the lower reaches of the Yellow River and the Xiashu loess deposits in the lower reaches of the Changjiang. We found that the Sr-Nd isotope composition was different between the loess in eastern China and the loess on the Chinese Loess Plateau, suggesting a different source region for the loess in eastern China. The Sr-Nd isotope data indicate that the loess deposits in eastern China mainly came from the near source. The loess deposits in the Shandong Peninsula and its adjacent coastal area show similar εNdvalues and 87Sr/86Sr ratios ranging from 0.7140 to 0.7155, which were blown from the Yellow River sediments exposed on the floodplain and the shelf during glacial times.The loess in the lower reaches of the Yellow River show similar Sr-Nd isotope values with the sediments in the floodplain of lower reaches of Yellow River, suggesting that the floodplain of lower reaches of Yellow River was the major source for the loess in the lower reaches of the Yellow River.The Xiashu loess deposits show 87Sr/86Sr ratios ranging from 0.7194 to 0.7209,which is lower than that of modern sediments in the lower reaches of the Changjiang,and εNd values ranging from-11.3 to-12.0. The source region of fine grains in Xiashu loess has not yet been determined and needs further study.The formation of loess deposits in eastern China may be related to the desertification during the glacial climate since the middle Pleistocene transition.关键词
Sr-Nd同位素/物源示踪/气候变化/长江/黄河Key words
Sr-Nd isotope/source tracing/climate change/Changjiang/Yellow River分类
天文与地球科学引用本文复制引用
郑力..中国东部主要黄土分布区的Sr-Nd同位素物源示踪研究[J].高校地质学报,2018,24(2):246-250,5.基金项目
国家自然科学基金项目(41730101)资助 （41730101）
