Tracing the provenance of aeolian loess in the Yangtze River Delta through zircon U–Pb age and geochemical investigations  

作　　者：QIAN Peng ZHENG Xiang-min CHENG Jun HAN Yu-jie DONG Yan ZHANG Jian-guo 

机构地区：[1]School of Geography, Nantong University [2]Department of Geography, East China Normal University [3]School of Geosciences, University of South Florida

出　　处：《Journal of Mountain Science》2018年第4期708-721,共14页山地科学学报（英文）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 41371032, 41671003, 41601189, 41672349)

摘　　要：Given the conflicts over the proposed formation mechanisms of Xiashu loess, the question of the provenance of sediments comprising the Xiashu loess in the Yangtze River Delta has not been satisfactorily resolved. In this study, the provenance of aeolian sediments of the Yangtze River Delta, China was examined by applying the detrial zircon U–Pb dating technique, Sr–Nd isotopic and trace element compositional analysis. U-Pb dating analysis was conducted on the Xiashu loess at three locations over the Yangtze River Delta, including Huangnishan(HNS) hill, Shengshan(SS) island and the Xuancheng(XC) area. The Xiashu loess and the sediments of the Yangtze River Valley share considerable similarity in their zircon U-Pb age spectra with the same main age peak and comparable age distribution. By contrast, significant differences in the age spectra, existbetween the Xiashu loess and loess deposits of Chinese Loess Plateau(CLP). Coarse grains of the Yangtze River Delta loess may have a proximal material source identical to the sediments from the Yangtze River valley. Sr–Nd isotopic values of the Xiashu loess match those from the northern margin of the Tibetan Plateau. Rare earth element ratios independent of grain size illustrate that the values from loess of the Yangtze River Delta mostly overlap with those of CLP loess. This feature implies that loess from the Yangtze River Delta has a dominant source of distant material similar as the CLP loess. As such, we conclude that multi-proxy analysis of sediments can shed new light on tracing the provenance of aeolian loess in the Yangtze River Delta.

关 键 词：Aeolian loess Provenance tracing Zircon U-Pb age GEOCHEMISTRY Yangtze River Delta 

分 类 号：S151[农业科学—土壤学]