摘要
绿纱铜（钴）矿床一直缺乏对矿床流体包裹体及同位素地球化学的研究,本文对与矿化密切相关的热液矿物开展了系统的流体包裹体岩相学、显微测温以及碳、氢、氧同位素研究.结果表明,矿区成矿流体具有中高温（220～500℃）、中高盐度（27.40％～42.60％NaCleq）、中等密度（0.79～1.17 g/cm3）的特征,成矿环境为低压（2.0～8.0 MPa）环境.同沉积初始富集阶段的成矿流体为含海相碳酸盐的岩石组合的变质脱水,晚期流体为变质流体与岩浆水的混合流体,并有不同程度的大气降水参与.热液中的碳早期由海相沉积碳酸盐岩经溶解作用提供,晚期为岩浆和海相沉积碳酸盐岩经溶解作用共同提供的.主成矿阶段的成矿流体存在三种端元,即高盐度、高温的岩浆流体（＞25％NaCleq,＞400℃）,高盐度、中高温的变质流体（＞25％ NaCleq,200～400℃）,低盐度和中低温的大气降水（＜10％NaCleq,150～300℃）,流体混合是矿区金属沉淀的重要机制.
The Cu-Co orebodies of the Lüsha deposit are hosted in the sedimentary strata of the Roan group,which is the lower part of the Neoproterozoic Katanga rock series.The regional geology characteristics indicate that ore-forming process of the deposit experienced three stages,early synsedimentary,middle tectonic metamorphic-hydrothermal modification and late secondary oxidation.The study results of temperature,salinity,density,pressure of fluid inclusions and C H O isotopic compositions in dolomite and quartz in various mineralization stages of the Luishia copper （cobalt） deposit demonstrate that the ore-forming fluid is a medium-high temperature （220-500℃）,medium high salinity （27.40％-42.60％NaCleq） and medium density （0.79-1.17 g/cm3） type.The metallogenic environment was at low pressure （2.0-8.0 MPa）.The ore-forming fluid at the initial stage originated from meta-morphic dehydration of rock assemblage containing marine carbonate,and the later period fluid originated from metamorphic fluid and magmatic water mixed fluid with different levels of atmospheric precipitation.Carbon isotopic compositions indicate that carbon at the initial stage was provided by the dissolution of marine sedimentary carbonate rocks,the later period carbon was provided by magma and the dissolution of marine sedimentary carbonate rocks.There are three end-members of fluids in the main metallogenic stage exists：high salinity （＞25％NaCleq） high temperature magmatic hydrothermal （＞400℃）,high salinity （＞25％NaCleq）medium-high temperature （200 -400℃）metamorphic fluid and low salinity （＜10％NaCleq）medium low temperature （150-300℃） atmospheric precipitation.The fluids mixing might be an important precipitation mechanism in this deposit.
出处
《矿物岩石地球化学通报》
CAS
CSCD
北大核心
2014年第5期711-720,共10页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
国土部国外矿产资源勘查专项(201120B04700102)
中铁资源集团有限公司2012年重点科技开发计划重点课题
