投稿时间:2017-09-04
修订日期:2018-02-08
网络发布日期:2018-04-25
中文摘要:玉海铜(钼)矿床成矿岩体为石英闪长(玢)岩,矿化呈细脉状、细脉-浸染状和稀疏浸染状。围岩蚀变主要为钾硅酸盐化、石英-绢云母化、青磐岩化和黏土化蚀变。矿床类型为斑岩型。铜(钼)矿化主要发育于钾硅酸盐化阶段、石英-绢云母化阶段和青磐岩化阶段。流体包裹体可划分为气液两相包裹体、含子晶三相包裹体和CO2包裹体3种类型。钾硅酸盐化阶段的均一温度为307~423℃,盐度w(NaCleq)为4.18%~10.11%,密度0.62~0.77 g/cm3,属于高温、中-低盐度流体;石英-绢云母化阶段均一温度为172~336℃,盐度为w(NaCleq)为3.23%~8.55%,密度0.70~0.93 g/cm3,属于中温、低盐度流体;晚期青磐岩化阶段均一温度155~296℃,盐度w(NaCleq)为3.71%~9.08%,密度0.80~0.96 g/cm3,属于中低温、低盐度流体。从早阶段到晚阶段,成矿流体温度逐渐下降,各成矿阶段成矿流体盐度均小于11%,但钾硅酸盐化阶段成矿流体盐度稍高。石英-绢云母化阶段成矿流体δD=-91.6‰~-72.1‰,δ18OH2O=-1.8‰~6.3‰;青磐岩化阶段成矿流体δD=-97.1‰~-68.3‰,δ18OH2O=-6.3‰~2.2‰;成矿流体具有岩浆水和大气降水混合特征,但青磐岩化阶段大气降水含量更高。硫化物的δ34S值为-3.5‰~2.8‰,硫来自石英闪长(玢)岩。
Abstract:The Yuhai porphyry Cu-(Mo) deposit is hosted by a quartz diorite (porphyrite) stock. Mineralization occurs as veinlets, veinlet-disseminations, and sparse disseminations, and is associated with quartz diorite (porphyrite). The wall-rock alterations include K-silicate alteration, quartz-sericite alteration, propylitic alteration and clay alteration. The mineralization can be divided into K-silicate stage, quartz-sericite stage and propylitic stage. Copper and molybdenum mineralization occurred at the every stage. Three types of fluid inclusions were recognized:vapor and liquid two-phase inclusions, daughter mineral-bearing three-phase inclusions and CO2 inclusions. Homogenization temperatures of fluid inclusions at the K-silicate stage range from 307℃ to 423℃ with salinities from 4.18% to 10.11% and densities from 0.62 g/cm3 to 0.77 g/cm3, indicating high temperature and middle to low salinity inclusions. Homogenization temperatures of fluid inclusions at the quartz-sericite stage range from 172℃ to 336℃ with salinities from 3.23% to 8.55% and densities from 0.70 g/cm3 to 0.93 g/cm3, indicating middle temperature and low salinity inclusions. Homogenization temperatures of the latest propylitic stage vary from 155℃ to 296℃ with salinities from 3.71% to 9.08% and densities from 0.80 g/cm3 to 0.96 g/cm3, indicating middle-low temperature and low salinity inclusions. Temperatures decreased gradually from early stage to late stage with the slightly high salinities at the K-silicate stage. The δ18OH2O values of the ore-forming fluids of the quartz-sericite stage range from -1.8‰ to 6.3‰ with δD from -91.6‰ to -72.1‰ while δ18OH2O values of the ore-forming fluids at the propylitic stage range from -6.3‰ to 2.2‰ with δD from -97.1‰ to -68.3‰,implying that ore-forming fluids were mixed magmatic fluids and meteoric water. Nevertheless, the quartz-sericite stage contained a higher portion of magmatic fluids than the propylitic stage. The δ34S values of sulfides range from -3.5‰ to 2.8‰. The sulfur in the Yuhai Cu-(Mo) deposit was derived from magma, i.e., from ore-forming quartz diorite (porphyrite).
keywords:geology fluid inclusions stable isotopes metallogenesis Yuhai Cu-(Mo) deposit eastern Tianshan Mountains
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基金项目:中国地质调查局地质调查项目(编号:12120115055601、DD20160007)资助
引用文本:
刘帅杰,余金杰,王铁柱,陆邦成,陈宝赟,陈寿波,黄宝强,王超.2018.新疆东天山玉海铜(钼)矿床流体包裹体和稳定同位素研究[J].矿床地质,37(2):371~386LIU ShuaiJie,YU JinJie,WANG TieZhu,LU BangCheng,CHEN BaoYun,CHEN ShouBo,HUANG BaoQiang,WANG Chao.2018.Fluid inclusions and stable isotope study of Yuhai copper-(molybdenum) deposit in eastern Tianshan Mountains, Xinjiang[J].Mineral Deposits37(2):371~386
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