泰国西部比洛克(Pilok)锡钨矿流体包裹体研究及矿床成因  

Fluid inclusion analysis and origin of the Pilok tin-tungsten deposit in western Thailand

作　　者：施美凤[1] 范文玉[1] 林方成[1] 王宏[1] 丛峰[1] 朱华平[1] 

机构地区：[1]中国地质调查局成都地质调查中心,四川成都610081

出　　处：《沉积与特提斯地质》2016年第2期97-104,共8页Sedimentary Geology and Tethyan Geology

基　　金：地质调查项目"全球重要成矿带成果集成与综合研究"(1212011220912)和"老挝-越南长山成矿带成矿规律与勘查靶区优选研究"(1212011120337)联合资助

摘　　要：对泰缅毗邻区比洛克锡钨矿区含矿石英脉进行了流体包裹体分析。包裹体岩相学研究表明，流体主要为富液相包裹体和H2O—CO2三相包裹体。显微测温分析结果显示，均一温度为200—350％，盐度（W（NaCl））为0．43％-12．42％，石英脉中H20-C02三相包裹体成矿压力为102—350mPa，估算成矿深度在0．34～1．37km。这些数据表明，石英脉型钨锡矿主要形成于岩浆演化晚期的中高温岩体顶部。结合前人稳定同位素等分析结果，认为比洛克锡钨矿存在4个矿化阶段：（1）早期高温产于细粒花岗岩内的黑钨矿±锡石±黄铁矿矿化；（2）与石英±钾长石脉有关的黑钨矿矿化；（3）叠加在中期钾化和钨矿化上的云英岩型锡矿化；（4）晚期中高温（220—350℃）低盐度（〈5％NaCleq.）混合流体为主的石英脉型钨锡矿化。结合研究区的区域构造演化及岩浆演化特征研究，建立了比洛克锡钨矿的找矿模型，并对该区进一步找矿提出建议。The fluid inclusion analysis is carried out in this study for the ore-bearing quartz veins from the Pilok tin- tungsten deposit in western Thailand. The fluid inclusions herein consist dominantly of liquid-rich inclusions and H2O-CO2 three-phase inclusions. The mierothermometric analysis indicates that these inclusions have the homogenization temperatures ranging between 200 and 350℃, the salinities between 0. 43% and 12. 42%, metallogenic pressures between 102 and 350 mPa, and estimated metallogenic depths between 0.34 and 1.37 km. All these data show that the quartz vein-type tin-tungsten deposit was formed in the topmost part of the mesothermal to high-temperature granites during the late stages of magmatie evolution. Referenced to the previous results, the Pilok tin-tungsten deposit has witnessed four stages of mineralization, including： （ 1 ） pegmatite-hosted wolframite ± cassiterite ± pyrite mineralization during the earlier high-temperature stage; （2） wolframite mineralization associated with quartz ± K-feldspar veins; （3） greisen-type tin mineralization following K-feldspar alteration and tungsten mineralization during the middle stage, and （4） quartz vein-type tin-tungsten mineralization characterized by mixed fluids with mesothermal to high-temperature （220 -350℃ ） and low salinities （ 〈 5% NaCleq. ） during the late stage. A metallogenetic model is constructed on the basis of the geology of the Pilok tin-tungsten deposit and regional tectonic evolution. The western Taninthayi Mountains in Myanmar are believed to be highly prospective for the exploration of the quartz vein-type or greisen-type tin-tungsten deposits.

关 键 词：钨锡矿 流体包裹体 找矿远景 泰国比洛克 东南亚 

分 类 号：P618.05[天文地球—矿床学]