投稿时间：2014-08-31
修订日期：2014-10-10
网络发布日期：2014-12-30
中文摘要:豫西火神庙中型矽卡岩型钼矿床位于华北陆块南缘栾川矿集区西部,赋存于火神庙岩体与新元古界三川组大理岩接触带的矽卡岩中。成矿过程可分为矽卡岩期(包括矽卡岩阶段和退化蚀变阶段)和石英-硫化物期(包括石英-钾长石阶段、石英-辉钼矿阶段、石英-黄铁矿阶段和石英-方解石阶段)。为查明成矿流体的性质、演化以及与成矿的关系,通过岩相学、显微测温和激光拉曼探针等实验对不同阶段、不同矿脉(物)发育的流体包裹体进行分析。结果表明:火神庙钼矿床主要发育气液两相包裹体、含子晶多相包裹体和H2O-CO2包裹体。流体包裹体均一温度介于102~600℃或者更高,盐度w(NaCleq)介于0~62%,密度介于0.46~1.31 g/cm3,成矿系统压力介于20~170 MPa,成矿古深度介于2~6.2 km。成矿流体主要为高温、中高盐度流体,总体属于H2O-NaCl±CO2±CH4体系。在大约5.4~6.2 km的古深度,火神庙岩体开始出溶成矿流体,在大约2~4.3 km的古深度,成矿流体经历了多次沸腾作用、混合作用及水-岩反应,逐渐由早阶段高温(>600℃)、中盐度〔w(NaCleq) 16.2%~18.3%〕的岩浆热液向晚阶段低温(102~253℃)、低盐度〔w(NaCleq) 0~2.6%〕的大气降水热液演化。成矿流体的多次沸腾和水-岩反应是导致辉钼矿沉淀的主要机制。
Abstract:The Huoshenmiao skarn Mo deposit in the west of the Luanchuan ore district at the southern edge of the North China Craton (NCC) is a medium-sized deposit, and the Mo orebodies are mainly hosted in the Huoshenmiao intrusion and Sanchuan marble. From early to late, the metallogenic process can be divided into skarn period and quartz-sulfide period. The skarn period can be further divided into skarn stage and retrograde stage, and the quartz-sulfide period can be further divided into quartz-K-feldspar stage, quartz-molybdenite stage, quartz-pyrite stage and quartz-calcite stage. In order to identify the characteristics of ore-forming fluids, evolution and the relationship with mineralization, the authors analyzed fluid inclusions in different veins or minerals of every stage by means of petrography, microscopic thermodynamics and Laser Raman. Three types of fluid inclusions were recognized in the deposit, namely aqueous two-phase, daughter mineral-bearing multiphase and CO2-bearing three-phase inclusions. The homogenization temperatures, salinities and densities of fluid inclusions vary from 102℃ to >600℃, from 0 to 62% NaCl eqv and from 0.46 g/cm3 to 1.31 g/cm3, respectively. The pressure and the depths of the metallogenic system vary in the range of 20~170 MPa and 2~6.2 km, respectively. The ore-forming fluid of the Huoshenmiao Mo deposit is characterized by high temperature and medium-high salinity, roughly belonging to the H2O-NaCl±CO2±CH4 system. It is thought that the exsolution of ore-forming fluids occurred at the depths of 5.4~6.2 km, and 2~4.3 km respectively, the ore-forming fluids gradually evolved from magmatic water to meteoric water by multiple boiling, mixing and water-rock reaction, and the multiple boiling of the ore-forming fluid and water-rock reaction seem to have been the leading mechanism for the deposition of molybdenite.
文章编号：
中图分类号：P618.65
文献标志码：
基金项目:本文得到国家科技支撑计划项目(编号:2011BAB04B06)、国土资源部公益性行业基金(编号:200911007-08)和国家自然科学基金项目(编号:41272104)资助
引用文本：
王赛,叶会寿,杨永强,苏慧敏,杨晨英,张佳磊.2014.豫西火神庙矽卡岩型钼矿床成矿流体研究[J].矿床地质,33(6):1233~1250WANG Sai,YE HuiShou,YANG YongQiang,SU HuiMin,YANG ChenYing,ZHANG JiaLei.2014.Ore-forming fluids of Huoshenmiao Mo Deposit, Western Henan[J].Mineral Deposits33(6):1233~1250
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