本文選題：成礦流體　切入點(diǎn)：沉積巖容礦脈狀銅礦床　出處：《吉林大學(xué)學(xué)報(bào)(地球科學(xué)版)》2017年03期

【摘要】：滇西北蘭坪盆地西緣發(fā)育大量沉積巖容礦脈狀銅多金屬礦床,礦體的分布受逆沖推覆系統(tǒng)控制,金滿是其中儲(chǔ)量最大、品位最高的銅礦床。成礦過程可分為3個(gè)階段:成礦前(不含礦化石英-鐵白云石脈)、主成礦階段(含銅硫化物石英脈)、晚成礦階段(少硫化物方解石+石英脈)。流體包裹體巖相學(xué)和顯微測溫結(jié)果表明:成礦前和主成礦期石英中流體包裹體特征變化不大,成礦前和主成礦期石英中均存在3種類型的包裹體,以水溶液包裹體為主,含CO_2水溶液包裹體次之,富CO_2包裹體較少出現(xiàn)。含CO_2水溶液包裹體測溫結(jié)果也差別不大,均一溫度都集中在240320℃,鹽度(w(NaCl))集中在1%4%。水溶液包裹體均一溫度變化也不大,集中在160 230℃,明顯低于含CO_2水溶液包裹體;鹽度卻存在較大的變化,主成礦期鹽度變化范圍明顯較大,且峰值高于成礦前。晚成礦階段則僅出現(xiàn)水溶液包裹體,均一溫度和鹽度都明顯降低,均一溫度集中在120185℃,鹽度集中在1.4%9.3%。結(jié)合其他證據(jù),筆者認(rèn)為金滿銅礦床包含兩種不同性質(zhì)的流體:深源流體,以中高溫、中低鹽度、富含CO_2為特征;盆地鹵水,以中低溫、中高鹽度、貧CO_2為特征。成礦過程中未發(fā)生明顯的沸騰和相分離作用,深源流體和盆地鹵水的混合可能是導(dǎo)致Cu等成礦元素沉淀的重要機(jī)制。
[Abstract]:In the western margin of Lanping basin in northwest Yunnan, a large number of sedimentary rock containing vein copper polymetallic deposits are developed. The distribution of orebodies is controlled by the thrusting and nappe system, in which the gold reserves are the largest. Copper deposit with the highest grade. The metallogenic process can be divided into three stages: before mineralization (no mineralized quartz-iron dolomite vein), main metallogenic stage (copper sulfide quartz vein), late metallogenic stage (oligosulphide calcite quartz vein). The petrographic and microthermometric results of fluid inclusions show that the characteristics of fluid inclusions in quartz before and during the main metallogenic period do not change much. There are three types of inclusions in quartz before and during the main metallogenic period. The main inclusions are aqueous inclusions, followed by aqueous inclusions containing CO_2, and the inclusions rich in CO_2 are rare. The results of temperature measurement of aqueous inclusions containing CO_2 are not different. The homogenization temperature is concentrated at 240320 鈩，

本文編號：1664334