{"title":"Genesis of Harizha Ag–Pb–Zn deposit in the eastern Kunlun Orogen, NW China: Evidence of fluid inclusions and C–H–O–S–Pb isotopes","authors":"Xingzhu Fan, F. Sun, Chenghan Xu, Wei Xin, Ying-chao Wang, Yong Zhang","doi":"10.1111/rge.12256","DOIUrl":null,"url":null,"abstract":"The Harizha Ag–Pb–Zn deposit is located in the eastern part of the eastern Kunlun Orogen, NW China. Two episodes including five paragenetic stages of vein mineralization has been recognized for the Harizha Ag–Pb–Zn deposit through petrographic observation: quartz + pyrite + arsenopyrite (Stage I), quartz + pyrite + chalcopyrite + pyrrhotite (Stage II), quartz + pyrite + chalcocite + pyrrhotite + sphalerite + galena + pyrargyrite (Stage III), quartz + calcite + pyrite + tetrahedrite + pyrolusite (Stage IV), and calcite + covellite + malachite + goethite + graphite (Stage V). In the quartz or calcite three types of fluid inclusions (FIs) were identified: L‐type, C‐type, and S‐type. The S‐type inclusions are only found in quartz in the wall rocks. The C‐type inclusions occur in quartz from early episodes (Stage I and II). The FIs from the early episodes homogenized at 240–320°C, with salinities of 9–12 wt.% NaCl equivalent. The ore‐forming fluids at the early episodes belong to an H2O–CO2–CH4–NaCl system. The FIs from late episodes (Stage III and IV) homogenized at 140–240°C, with salinities of 2–8 wt% NaCl equivalent. The ore‐forming fluids from the late episodes are dominated by an H2O–NaCl fluid system. The HO and CO isotopic compositions of quartz and calcite indicate that the ore‐forming fluids were derived from a primary magmatic‐hydrothermal system, with subsequent meteoric water involvement at a later stage. Sulfides have δ34S values of −3.7 to –1.0‰, and 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios ranging from 18.381 to 18.425, 15.661 to 15.683, and 38.498 to 38.677, respectively. These likely suggest a magmatic sulfur affinity combined with the ore features, mineral associations, alteration characteristics, ore‐forming environment, and fluid evolutionary process. We conclude that the Harizha Ag–Pb–Zn deposit is a typical medium‐low temperature hydrothermal deposit.","PeriodicalId":21089,"journal":{"name":"Resource Geology","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2021-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Resource Geology","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1111/rge.12256","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOLOGY","Score":null,"Total":0}
引用次数: 4
Abstract
The Harizha Ag–Pb–Zn deposit is located in the eastern part of the eastern Kunlun Orogen, NW China. Two episodes including five paragenetic stages of vein mineralization has been recognized for the Harizha Ag–Pb–Zn deposit through petrographic observation: quartz + pyrite + arsenopyrite (Stage I), quartz + pyrite + chalcopyrite + pyrrhotite (Stage II), quartz + pyrite + chalcocite + pyrrhotite + sphalerite + galena + pyrargyrite (Stage III), quartz + calcite + pyrite + tetrahedrite + pyrolusite (Stage IV), and calcite + covellite + malachite + goethite + graphite (Stage V). In the quartz or calcite three types of fluid inclusions (FIs) were identified: L‐type, C‐type, and S‐type. The S‐type inclusions are only found in quartz in the wall rocks. The C‐type inclusions occur in quartz from early episodes (Stage I and II). The FIs from the early episodes homogenized at 240–320°C, with salinities of 9–12 wt.% NaCl equivalent. The ore‐forming fluids at the early episodes belong to an H2O–CO2–CH4–NaCl system. The FIs from late episodes (Stage III and IV) homogenized at 140–240°C, with salinities of 2–8 wt% NaCl equivalent. The ore‐forming fluids from the late episodes are dominated by an H2O–NaCl fluid system. The HO and CO isotopic compositions of quartz and calcite indicate that the ore‐forming fluids were derived from a primary magmatic‐hydrothermal system, with subsequent meteoric water involvement at a later stage. Sulfides have δ34S values of −3.7 to –1.0‰, and 206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb ratios ranging from 18.381 to 18.425, 15.661 to 15.683, and 38.498 to 38.677, respectively. These likely suggest a magmatic sulfur affinity combined with the ore features, mineral associations, alteration characteristics, ore‐forming environment, and fluid evolutionary process. We conclude that the Harizha Ag–Pb–Zn deposit is a typical medium‐low temperature hydrothermal deposit.
期刊介绍:
Resource Geology is an international journal focusing on economic geology, geochemistry and environmental geology. Its purpose is to contribute to the promotion of earth sciences related to metallic and non-metallic mineral deposits mainly in Asia, Oceania and the Circum-Pacific region, although other parts of the world are also considered.
Launched in 1998 by the Society for Resource Geology, the journal is published quarterly in English, making it more accessible to the international geological community. The journal publishes high quality papers of interest to those engaged in research and exploration of mineral deposits.