Sedimentary Paleoenvironment of the Eastern Hexi Corridor, NW China: Constraints from Chert Geochemistry and Sedimentary Analysis of Early Paleozoic Strata  

作　　者：ZHANG Yiping CHEN Xuanhua AVZUZA ZHANG Beihang ZHAO Heng 

机构地区：[1]Chinese Academy of Geological Sciences,Beijing 100037,China [2]Nevada Bureau of Mines and Geology,University of Nevada,Reno,89557,USA [3]Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China

出　　处：《Acta Geologica Sinica(English Edition)》2020年第4期1223-1237,共15页地质学报（英文版）

基　　金：supported by the National Program for the National Natural Science Foundation of China(41972224);the Fundamental Research Funds for the Chinese Academy of Geological Sciences(JKY202011);Key Basic Research Project from the Ministry of Science and Technology of the People’s Republic of China(2018YFC0603700);the Chinese Geological Survey(DD20190011,DD20189132,DD20190129)。

摘　　要：The eastern Hexi Corridor, northwest China, is located at the tectonic junction of the Alxa Block, the North China Craton, and the Qinling-Qilian Orogen. The early Paleozoic Xiangshan Group record critical information regarding paleoenvironment, paleoclimate and paleotectonic setting, from which we here present a focused study on the chert beds within the Xiangshan Group. Through field mapping, microstructural observation, whole-rock geochemistry analyses and detrital zircon dating, we suggest that the Xiangshan Group chert was deposited along a passive continental margin, formed primarily through biological activity with minor hydrothermal influence and terrestrial input. The characteristics of the chert support a low latitude sedimentary paleoenvironmental origin, and reveal the fact that the Alxa Block was separated from the North China craton, while emerged some paleogeographic affinity with the Qilian region in the Middle-Late Cambrian.

关 键 词：GEOCHEMISTRY sedimentary paleoenvironment Early Paleozoic Xiangshan Group chert Hexi Corridor 

分 类 号：P59[天文地球—地球化学] P512.2[天文地球—地质学]