| 陕西商南三官庙金矿床流体包裹体及C-H-O-S稳定同位素研究 |
| |
| 引用本文： | 汪超,王瑞廷,刘云华,薛玉山,胡西顺,牛亮.陕西商南三官庙金矿床流体包裹体及C-H-O-S稳定同位素研究[J].现代地质,2021,35(6):1551-1564. |
| |
| 作者姓名： | 汪超 王瑞廷 刘云华 薛玉山 胡西顺 牛亮 |
| |
| 作者单位： | 1.长安大学 地球科学与资源学院,陕西 西安 7100542.西安西北有色地质研究院有限公司,陕西 西安 7100543.陕西省矿产资源综合利用工程技术研究中心,陕西 西安 7100544.西北有色地质矿业集团有限公司,陕西 西安 710054 |
| |
| 基金项目： | 中国地质调查局项目“矿集区矿产调查和深部找矿预测”(DD2019057018);陕西省地勘基金项目(61201707317);国家自然科学基金面上项目(41872219) |
| |
| 摘 要： | 三官庙金矿床位于秦岭造山带南秦岭北部逆冲推覆构造带内,为断裂构造控矿的热液型矿床。热液成矿期划分为成矿早阶段(S1)、主阶段(S2)和晚阶段(S3)。成矿主阶段流体包裹体的完全均一温度Th为150~420 ℃,盐度为2.1%~24.1%;成矿晚阶段Th为81~190 ℃,盐度为5.6%~22.2%。包裹体研究显示,在成矿主阶段温度>250 ℃时,以流体混合作用为主而导致矿物沉淀;在成矿主阶段温度<250 ℃及成矿晚阶段,以流体沸腾作用为主而导致矿物沉淀。成矿主阶段成矿流体的δDV-SMOW为-84.4‰~-77.0‰,δ18${{\text{O}}_{{{\text{H}}_{2}}\text{O}}}$为5.0‰~5.7‰,成矿流体来源以岩浆水为主,同时混入了外来流体。成矿流体的δ13CΣC为-13.5‰~-5.2‰,反映碳为岩浆来源并受到低温蚀变的影响。黄铁矿单矿物δ34SCDT为-2.73‰~-1.31‰;毒砂单矿物δ34SCDT为-3.36‰~0.03‰,反映成矿物质硫为典型的单一岩浆来源。综上分析,认为三官庙金矿床为岩浆热液成因,其成矿机制为:印支期末,在钠长(角砾)岩形成过程中,含金热液流体沿断裂构造运移,在距离钠长(角砾)岩较远地段的层间破碎带内,成矿流体发生混合及沸腾作用,促使成矿物质发生沉淀,最终形成三官庙金矿床。
|
| 关 键 词： | 流体包裹体 C-H-O-S稳定同位素 矿床成因 三官庙金矿床 陕西商南 |
| 收稿时间： | 2021-06-21 |
| 修稿时间： | 2021-10-12 |
Fluid Inclusion and C-H-O-S Stable Isotopic Studies of Sanguanmiao Gold Deposit,Shangnan, Shaanxi Province |
| |
| WANG Chao,WANG Ruiting,LIU Yunhua,XUE Yushan,HU Xishun,NIU Liang.Fluid Inclusion and C-H-O-S Stable Isotopic Studies of Sanguanmiao Gold Deposit,Shangnan, Shaanxi Province[J].Geoscience——Journal of Graduate School,China University of Geosciences,2021,35(6):1551-1564. |
| |
| Authors: | WANG Chao WANG Ruiting LIU Yunhua XUE Yushan HU Xishun NIU Liang |
| |
| Institution: | 1. School of Earth Science and Resources, Chang'an University, Xi'an, Shaanxi 710054, China2. Xi'an Northwest Geology Research Institute of Nonferrous Metals Co., Ltd., Xi'an, Shaanxi 710054, China3. Shaanxi Engineering Technology Research Center of Comprehensive Utilization of Mineral Resources, Xi'an, Shaanxi 710054, China4. Northwest Nonferrous Geological and Mining Group Co., Ltd., Xi'an, Shaanxi 710054, China |
| |
| Abstract: | The Sanguanmiao gold deposit is located in the thrust-nappe belt in the northern South Qinling Orogen. It is a fault-controlled magmatic-hydrothermal deposit. Gold mineralization at Sanguanmiao can be divided into pre-ore (S1), main-ore (S2) and post-ore (S3) stages. Massive sulfide and calcite-quartz veins with gold mineralization were formed in S2. The homogenization temperatures (Th) of S2 fluid inclusions are of 150-420 ℃, with salinities of 2.07%-24.15%NaCl, whereas the S3 ores are of 81-190 ℃ and 8.55%-22.17%NaCl. Fluid inclusion petrologic and microthermometric analyses show that the gold precipitation was resulted from fluid mixing and subsequent fluid boiling during the main ore stage. The δDV-SMOW values of the S2 ore-forming fluid range from -84.4‰ to -77.0‰, and the δ18${{\text{O}}_{{{\text{H}}_{2}}\text{O}}}$ values range from 5.0‰ to 5.7‰, indicating the mixing of magmatic water and meteoric fluids. The ore-fluid δ13CΣC values range from -13.5‰ to -5.2‰, indicating a magmatic carbon origin influenced by low-temperature alteration. The δ34SCDT values range from -2.73‰ to -1.31‰ for pyrite, and from -3.36‰ to 0.03‰ for arsenopyrite, suggesting a single magmatic sulfur source. Thus, we considered that the Sanguanmiao gold deposit is associated with magmatic-hydrothermal activity, and proposed a metallogenic model as follows: the gold-bearing hydrothermal fluids migrated along fault structures during the late Indosinian Orogeny. Fluid mixing and boiling then occurred in the interlayer fracture zone, which caused gold precipitation and eventually the Sanguanmiao gold mineralization. |
| |
| Keywords: | fluid inclusion C-H-O-S stable isotope ore genesis Sanguanmiao gold deposit Shangnan Shaanxi |
|
| 点击此处可从《现代地质》浏览原始摘要信息 |
| 点击此处可从《现代地质》下载免费的PDF全文 |
|
