文献类型：期刊文献

英文题名：Age and petrogenesis of Anisian magnesian alkali basalts and their genetic association with the Kafang stratiform Cu deposit in the Gejiu supergiant tin-polymetallic district, SW China

作者：Zhang, Jiawei Dai, Chuangu Huang, Zhilong Luo, Taiyi Qian, Zhikuan Zhang, Ying

第一作者：Zhang, Jiawei

通信作者：Huang, ZL[1]

机构：[1]Bur Geol & Mineral Explorat & Dev Guizhou Prov, Guizhou Geol Survey, Guiyang 550005, Peoples R China;[2]Chinese Acad Sci, Inst Geochem, State Key Lab Ore Deposit Geochem, Guiyang 550081, Peoples R China;[3]Guizhou Mingzu Univ, Architectural Engn Coll, Guiyang 550025, Peoples R China;[4]Guizhou Inst Technol, Dept Resource & Environm Engn, Guiyang 550003, Peoples R China

第一机构：Bur Geol & Mineral Explorat & Dev Guizhou Prov, Guizhou Geol Survey, Guiyang 550005, Peoples R China

通信机构：corresponding author), Chinese Acad Sci, Inst Geochem, State Key Lab Ore Deposit Geochem, Guiyang 550081, Peoples R China.

年份：2015

卷号：69

起止页码：403-416

外文期刊名：ORE GEOLOGY REVIEWS

收录：;EI(收录号：20152200888312);Scopus(收录号：2-s2.0-84929761970);WOS:【SCI-EXPANDED(收录号:WOS:000356754500023)】；

基金：This study was financially supported by the Crisis Mines Continued Resources Exploration Project, China Geological Survey (No. 2008186); the Guizhou 1:50000 Geological Survey Projects of Dushan, Hezhai, Jialiang and Zhouqin, Guizhou Province, China Geological Survey (No. 12120114072801); and the Guizhou 1:50000 Geological Survey Projects of Fanjingshan, Dewang, Jiangkou and Kaide, China Geological Survey (No. 1212011120622). We appreciate the assistance of Jing Hu, Guangping Bao, and Van Huang in the trace element analyses. We thank Liang Qi, Lin Ye and Hong Zhong for their advice. We are grateful to Yulong Yang, Hongpeng Fan Pingping Liu and Chengbiao Leng for their revisions of the manuscript. Editor Franco Pirajno and two anonymous reviewers are especially thanked for their valuable comments and suggestions.

语种：英文

外文关键词：Gejiu basalts; Kafang stratiform Cu deposit; Ore genesis; Tectonic setting; Hydrothermal alteration; SW China

摘要：Gejiu is geographically located near Gejiu city, SW China. It is one of the largest tin-polymetallic districts in the world and contains approximately 3 million tons (Mt) of Sn and smaller quantities of Cu, Pb, and Zn. The deposit primarily yields three different types of ore: skarn-hosted ore, basalt-hosted stratiform ore, and carbonate-hosted stratiform ore. Kafang is one of the primary ore deposits in the Gejiu district and is an unusual occurrence hosted in basaltic rocks. Genetic models of the Kafang deposit suggest that it is related either to Anisian (Lower stage of Middle Triassic) Gejiu basalts or to Cretaceous Gejiu granite. In this study, we performed zircon SIMS U-Pb dating, major and trace element analyses, and Sr-Nd-Pb isotopic analyses for the Gejiu basalts and S isotopic analyses for stratiform Cu ore. Our results and previous studies are used to interpret the pet:rogenesis of the Gejiu basalts and the origin of the basalt-hosted stratiform Cu deposit. The SIMS zircon U-Pb analyses of the Gejiu basalts yield an age of 244.4 Ma. The trace element ratios of the Gejiu basalts are similar to those of ocean island basalt and have positive epsilon Nd(t) values (ranging from 0.6 to 2.5) and uniform (Sr-87/Sr-86); values (ranging from 0.70424 to 0.70488). These ratios are close to those of the Permian Emeishan flood basalt. Thus, the Gejiu basalts may represent coeval volcanisms within the plate involving remelting of the Emeishan plume head through a stress relaxation process after the main plume event. The Pb and S isotopic compositions of the Gejiu basalts and the stratiform Cu ores indicate that the source of Cu and S is primarily derived from the Gejiu basalts. However, the age of sulfide mineralization (84.2-79.6 Ma) and the age of hydrothermal alteration (85.5-81.9 Ma) are temporally consistent with the age of the Cretaceous granite emplacement (85.5-833 Ma). From a petrological and geochemical study, we determine that the Gejiu basalts may have been subjected to pervasive granite-related hydrothermal alteration during the emplacement of granite. These processes increase the K and Mg contents of basalt and probably caused the formation of the Cu ores. Thus, the Kafang stratiform Cu deposit can be considered as a granite-related hydrothermal deposit. (C) 2015 Elsevier B.V. All rights reserved.