Sedimentary Environment and Mineralization of the Black Shale Polymetallic Layer in the Early Cambrian,SW China:Constraints from in situ LA-ICP-MS Analysis of Pyrite  

作　　者：YANG Zhen FU Yong LI Chao CAI Xi GUO Chuan 

机构地区：[1]College of Eco-Environmental Engineering,Guizhou Minzu University,Guiyang 550025,China [2]College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China [3]Key Laboratory of Karst Georesources and the Environment,Ministry of Education,Guizhou University,Guiyang 500025,China [4]National Research Center for Geoanalysis,Chinese Academy of Geological Sciences,Beijing 100037,China

出　　处：《Acta Geologica Sinica(English Edition)》2024年第2期416-429,共14页地质学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42272103,92062221,42063009,U1812402);the Guizhou Provincial Science and Technology Projects(Grant No.Qiankehejichu–ZK[2022]common 213);the Higher Education Scientific Research Projects of the Education Department of Guizhou Province(Grant No.Qianjiaoji[2022]157).

摘　　要：A polymetallic layer is usually developed at the bottom of the early Cambrian black shale in Guizhou Province.The mineral that makes up the polymetallic layer is related to the sedimentary facies.To analyze the differentiation mechanism between polymetallic deposits(Ni-Mo and V),the Zhijin Gezhongwu profile located in the outer shelf and the Sansui Haishan V deposit located in the lower slope are selected to study the in situ sulfur isotopes and trace elements of pyrite.The results show that δ^(34)S values of pyrite vary widely from−7.8‰to 28‰in the Gezhongwu profile,while the δ^(34)S values are relatively uniform(from 27.8‰to 38.4‰)in the Haishan profile.The isotopic S composition is consistent with the transition that occurs in the sedimentary phase from the shelf to the deep sea on the transgressive Yangtze platform;this indicates that the δ^(34)SO_(4)^(2−)values in seawater must be differently distributed in depositional environments.The sulfur in the Ni-Mo layer is produced after the mixing of seawater and hydrothermal fluid,while the V layer mainly originates from seawater.Overall,the Ni-Mo and V deposits have been differentiated primarily on the basis of the combined effect of continental weathering and hydrothermal fluid.

关 键 词：sedimentary environment black shale polymetallic layer PYRITE early Cambrian 

分 类 号：P618.2[天文地球—矿床学]