摘要
红石金矿床是新疆东天山康古尔塔格金矿带中的代表性矿床之一,本文对其进行了比较系统的流体包裹体和稳定同位素研究。流体包裹体研究结果表明,红石金矿床的成矿流体为中低温、低盐度、中低密度的富 CO_2流体。石英氢同位素组成δD_(SMOW)为-104‰～-63‰,石英氧同位素组成δ^(18)O_(石英)为13.8‰～15.5‰、δ^(18)O_水为-1.7‰～6.1‰。方解石碳同位素组成δ^(13)C_(PDB)为-3.5‰～-2.7‰,方解石氧同位素组成δ^(18)_(PDB)为-28.9‰～-26.5‰、δ^(18)O_(SMOW)为1.1‰～3.5‰。H、O、C 同位素组成特征指示红石金矿床成矿流体主要起源于深部,后期混合有大气水。黄铁矿硫同位素组成δ^(34)S 为-11.5‰～3.8‰,集中于0.4‰～3.8‰,平均值为1.73‰,指示了成矿物质中的硫具有接近陨石硫的深源特征。红石金矿床的成矿作用可概括为富含成矿元素的深源流体在区域剪切构造作用下沿剪切系统不断向上运移,逐渐与浅部流体混合并与围岩发生交代蚀变作用,由于物理化学条件的改变,成矿元素最终在剪切扩容空间中富集成矿。
Abstract The Hongshi gold deposit is one of typical deposits from the Kanggurtag gold belt in the Eastern Tianshan, Xinjiang, NW China. Fluid inclusion and H, O, C, and S stable isotopic studies on the deposit have been carried out in this paper. The obtained data from fluid inclusion study indicate that the ore-forming fluids are rich in CO2 and characterized by middle-low temperature, low salinity, and middle-low density. Concurrently, hydrogen （δDSMOW=-104‰～-63‰） and oxygen （δ^18O石英=13.8‰～15.5‰,δ^18O水=-1.7‰～6.1‰） isotopic compositions of quartz, and carbon （δ^13CpDm=-3.5‰～-2.7‰） and oxygen （δ^18 OpDB=-28.9‰～- 26.5‰、δ^OSMOW=1.1‰～3.5‰） isotopic compositions of calcite indicate that the ore-forming fluids are derived from the both the deep fluid and the magmatic fluid, and mixed with meteoric water at last stage. Sulfur isotopes of pyrite range -11.5‰～3.8‰ with average value of 1.73‰,implying the sulfur of ore-forming materials is characterized by deep-seated sulfur similar to that of meteorite. Briefly, the mineralization process of the Hongshi gold deposit can be summarized as follows： In the regional shearing regime, the deep fluids rich in metallogenic elements flow upward inside the shear system, and mixed eventually with the shallow fluids, and experience the replacement with country rocks. Finally, metallogenic elements concentrate and deposit within the shear zone due to the change of physical-chemical conditions in the shallow level.
出处
《岩石学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第8期1998-2006,共9页
Acta Petrologica Sinica
基金
国家重点基础研究规划项目课题(2007CB411302和2001CB409807)资助成果。
