Genesis of the Changba–Lijiagou Giant Pb-Zn Deposit, West Qinling, Central China: Constraints from S-Pb-C-O isotopes

作     者：WEI Ran WANG Yitian MAO Jingwen HU Qiaoqing QIN Siting LIU Shengyou YE Dejin YUAN Qunhu DOU Ping WEI Ran;WANG Yitian;MAO Jingwen;HU Qiaoqing;QIN Siting;LIU Shengyou;YE Dejin;YUAN Qunhu;DOU Ping

作者机构：School of Earth Science and Resources Chang'anUniversityXi'an 710064China MNR Key Laboratory of Metallogeny and Mineral Resource AssessmentInstitute of Mineral ResourcesChina Academy of Geological SciencesBeijing 100037China Geological Survey of Gansu ProvinceLanzhou 730030China Changba Pb-Zn Mine of Baiyin Nonferrous Metals CompanyChengxianGansu 742500China 

出 版 物：《Acta Geologica Sinica(English Edition)》 (地质学报（英文版）)

年 卷 期：2020年第94卷第4期

页      面：884-900页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported and funded by the Special Research Funding for Public Benefit sponsored by MLR(Grant No.200911007-21) the Fundamental Research Funds for the Central Public Welfare Research Institutes(Grant No.K1612 and K1607) the Fundamental Research Funds for the Central Universities(Grant No.300102279401) the Geological Survey Project(Grant No.N1916)and(Grant No.DD20190368) 

主　　题：S-Pb isotopes C-O isotopes Pb-Zn deposit ore genesis epigenetic hydrothermal Changba–Lijiagou West Qinling 

摘      要：The extensive Changba-Lijiagou Pb-Zn deposit is located in the north of the Xihe–Chengxian ore cluster in West Qinling. The ore bodies are mainly hosted in the marble, dolomitic marble and biotite-calcite-quartz schist of the Middle Devonian Anjiacha Formation, and are structurally controlled by the fault and anticline. The ore-forming process can be divided into three main stages, based on field geological features and mineral assemblages. The mineral assemblages of hydrothermal stage I are pale-yellow coarse grain, low Fe sphalerite, pyrite with pits, barite and biotite. The mineral assemblages of hydrothermal stage II are black-brown cryptocrystalline, high Fe shalerite, pyrite without pits, marcasite or arsenopyrite replace the pyrite with pits, K-feldspar. The features of hydrothermal stage III are calcite-quartz-sulfide vein cutting the laminated, banded ore body. Forty-two sulfur isotope analyses, twenty-five lead isotope analyses and nineteen carbon and oxygen isotope analyses were determined on sphalerite, pyrite, galena and calcite. The δ34 S values of stage I(20.3 to 29.0‰) are consistent with the δ34 S of sulfate(barite) in the stratum. Combined with geological feature, inclusion characteristics and EPMA data, we propose that TSR has played a key role in the formation of the sulfides in stage I. The δ34 S values of stage II sphalerite and pyrite(15.1 to 23.0‰) are between sulfides in the host rock, magmatic sulfur and the sulfate(barite) in the stratum. This result suggests that multiple S reservoirs were the sources for S2-in stage II. The δ34 S values of stage III(13.1 to 22‰) combined with the structure of the geological and mineral features suggest a magmatic hydrothermal origin of the mineralization. The lead isotope compositions of the sulfides have 206 Pb/204 Pb ranging from 17.9480 to 17.9782, 207 Pb/204 Pb ranging from 15.611 to 15.622, and 208 Pb/204 Pb ranging from 38.1368 to 38.1691 in the three ore-forming stages. The narrow and symmetric di