Early Silurian Wuchuan–Sihui–Shaoguan exhalative sedimentary pyrite belt, South China: constraints from zircon dating for K-bentonite of the giant Dajiangping deposit  

作　　者：Yingying Zhang Taiyi Luo Tian Gan Mingzhong Zhou Xinqiao Han 

机构地区：[1]The State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,China [2]College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 101407,China [3]International Center for Planetary Sciences,College of Geosciences,Chengdu University of Technology,Chengdu 610059,China [4]School of Geographical and Environmental Sciences,Guizhou Normal University,Guiyang 550001,China [5]'Guangdong Guangye Yunliu Pyrite Mining Co.,LTD,Yunfu 527300,China

出　　处：《Acta Geochimica》2021年第1期1-12,共12页地球化学学报（英文）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.41873058 and 41462001);the Natural Science and Technology Foundation of Guizhou Province,China(Grant No.JZ[2015]2009)。

摘　　要：The Wuchuan-Sihui-Shaoguan(WSS)exhalative sedimentary pyrite belt in the southwestern part of the Qinzhou-Hangzhou(Qin-Hang)belt is the most important sulfur industry base in China.However,a wide range of metallogenetic ages spanning from Ediacaran to Devonian has been reported in the literature.This age range does not support the idea that the typical character of"coeval mineralization"in an exhalative sedimentary mineralization belt in China and worldwide.Therefore,the precise determination of mineralization ages of representative deposits is necessary to provide guides for exploration and metallogenetic models.The Dajiangping pyrite deposit is a typical example of this kind of deposits and is also the largest deposit with a proven reserve of 210 Mt.This deposit was thought to have formed in Ediacaran or Devonian.In this study,2-3 layers of 10-25 cm thick 2M1-type microcrystalline muscovite slate abruptly embedded in the No.Ⅳmassive orebody of the deposit has been identified to be low-grade metamorphic K-bentonite.A Concordia zircon LA-ICP-MS U-Pb age of 432.5±1.3 Ma(mean standard weighted deviation of concordance and equivalence=1.2;N=11)has been yielded for the low-grade metamorphic K-bentonite.This age is distinctly different from the Rb-Sr isochron age of630.1±7.3 Ma for siliceous rock at the top of the No.Ⅲbanded orebody and the Re-Os isochron age of 389±62 Ma for pyrites from a laminated orebody.Instead,it is close to the intercept age(429 Ma)of the youngest detrital zircons from sandstone interlayers of the No.Ⅲbanded orebody.The Concordia age is also coincident with those of the Late Caledonian(400-460 Ma)magmatism-metamorphism events which are widely distributed in Cathaysia Block.Particularly,it agrees well with that of the Early Silurian extensional volcanism(434-444 Ma)which have been revealed in the Dabaoshan,Siqian-Hekou,and Nanjing volcanic basins in northern Guangdong Province and southern Jiangxi Province.Hence,the dating result in this study confirms that the sedimentary time of the o

关 键 词：Wuchuan–Sihui–Shaoguan exhalative sedimentary pyrite belt Dajiangping pyrite deposit Lowgrade metamorphic K-bentonite Zircon U–Pb dating 

分 类 号：P578.292[天文地球—矿物学]