摘要
吉林大黑山超大型钼矿床是中亚-兴蒙造山带东段的斑岩型钼矿床之一,矿体产于燕山期花岗闪长斑岩体和不等粒花岗闪长岩体中,与下古生界头道沟组变质火山岩地层关系密切。流体包裹体研究表明,大黑山钼矿床主要发育气液两相和含子矿物三相两类包裹体。成矿流体反映了较连续的演化过程,成矿早-中阶段发育气液两相水溶液包裹体及含子矿物三相包裹体,均一温度为300℃～460℃,流体盐度为1.7 wt%～49.92 wt%NaCl eqv,该阶段流体经减压沸腾作用,导致大规模矿质沉淀,为大黑山钼矿床的主成矿阶段;成矿晚阶段由于大气降水的大量混入,发育气液两相水溶液包裹体,均一温度为196.5℃～300℃,流体盐度为1.7 wt%～7.1 wt%NaCl eqv,成矿流体总体上属H2O-NaCl体系。流体沸腾作用是金属硫化物大量沉淀的主要机制,该矿床形成于陆缘弧环境。
Daheishan super-large molybdenum deposit of Jilin is one of the porphyry molybdenum deposits in central Asia——Hinggan Mongolian orogenic belt.The ore bodies are yielded in the Yanshanian granodiorite porphyry and unequal particle granodiorite,and closely related with Toudaogou metamorphic volcanic rocks of Lower Paleozoic.The research on fluid inclusions showed that the samples mainly developed gas-liquid two-phase inclusions and daughter minerals-bearing three-phase inclusions in Daheishan deposit.The ore-forming fluids reflected a continuous evolution process,forming gas-liquid two-phase aqueous inclusions and daughter minerals-bearing three-phase inclusions in early-middle stage,and the homogenization temperatures between 300 ℃~460 ℃ and fluid salinity between 1.7 wt%~49.92 wt% NaCl eqv.In this stage,the fluids underwent decompression and boiling action and resulted in laege-scale mineral precipitation,which was also the main mineralization stage.In later stage,gas-liquid two-phase aqueous inclusions were developed mixing with meteoric water.The homogenization temperature is 196.5 ℃~300 ℃ and fluid salinity is 1.7 wt%~7.1 wt% NaCl eqv,belonging to H2O-NaCl system.Fluid boiling action was the main mechanism of metal sulfides precipitate.The Daheishan molybdenum deposit formed in the continental marginal arc environment.
出处
《世界地质》
CAS
CSCD
2012年第1期58-67,共10页
World Geology
基金
吉黑东部成矿规律和找矿方向综合研究(资[2010]矿评01-20-06)
关键词
流体包裹体
矿床成因
大黑山钼矿床
吉林省
fluid inclusion
deposit genesis
Daheishan molybdenum deposit
Jilin Province
