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兰坪-思茅中新生代盆地沉积岩中产出一系列热液型铜矿床(矿点),以石英、铁白云石与含铜硫化物(包括黄铜矿、斑铜矿、黝铜矿和辉铜矿)为主,呈脉状产于砂岩、页岩中,而单独的黝铜矿、方解石和重晶石脉则产于底部碳酸盐岩中.红色碎屑岩中的浅色还原层内的细脉和裂隙中也具有铜矿化。矿石构造以角砾状、脉状最为发育,矿脉多位于褶皱与走向断裂破碎带的叠加部位。金满铜矿的Sr、S、Ph同位素证据、稀土元素地球化学及液体包裹体资料表明,成矿元素主要来自沉积岩层,合矿卤水属于盆地卤水,流来自于硫酸盐的还原作用及沉积硫化物的淋滤溶解作用。含矿流体是H。O-NaCI~CO。体系卤水,成矿温度为150~300C,流体盐度为5%~20%NaCI。据含CO2包裹体的测温资料估算成矿压力大于6X10'Pa,相当于3km深的静岩压力。根据铜矿床成因研究,笔者提出了含矿热卤水储备与突发成矿作用的成矿模式。成矿前,矿化卤水象石油天然气一样,首先集中到一定的构造部位,在构造活动期突然爆炸成矿。成矿期由3个阶段组成,即爆炸充填、渗透充填与改造阶段,热液活动主要在前两个阶段。
A series of hydrothermal copper deposits (gold deposits) have been produced in the Lanping-Simao Mesozoic sedimentary rocks. Quartz, iron dolomite and copper-bearing sulfides (including chalcopyrite, bornite, tetrahedrite and Chalcopyrite), vein-shaped in sandstone and shale, and separate tetrahedrite, calcite and barite veins from the bottom carbonate. Copper mineralization is also present in the veins and fissures in the light-colored reductive layers in the red clastic rocks. The ore structure is brecciated and the veins are the most developed. The veins are mostly located at the superimposed part of the fold and strike-breaking fault zone. The Sr, S, Ph isotopic evidence, REE geochemistry and fluid inclusions in the Jinman copper deposit indicate that the metallogenic elements mainly come from sedimentary rocks. The ore-forming brine belongs to the basin brine and the flow comes from the reduction of sulphate and the deposition and sulphide Leaching and dissolving effect. The ore-bearing fluid is H. O-NaCI ~ CO. System brine, mineralization temperature of 150 ~ 300C, fluid salinity of 5% to 20% NaCI. According to the temperature measurement data of CO2 inclusions, the metallogenetic pressure is estimated to be more than 6X10’Pa, which is equivalent to the rock pressure of 3km deep. According to the research on the genesis of copper deposits, the authors put forward the metallogenic model of ore-bearing hot brine reserves and sudden mineralization. Before mineralization, mineralized brine, like oil and gas, was first concentrated in certain tectonic parts and suddenly exploded into ore during the tectonic activity. The metallogenetic stage consists of three phases, namely, explosive charge, infiltration charge and reform phase, hydrothermal activity mainly in the first two stages.