青海省卡尔却卡铜多金属矿床流体包裹体特征及成矿流体  

Characteristics of fluid inclusions and origin of Kaerqueka copper polymetallic deposit, Qinghai Province

作　　者：宋文彬[1,2] 赖健清[1,2] 黄敏[1,2] 杨自安 张普斌 欧阳华平[1,2] 

机构地区：[1]中南大学有色金属成矿预测教育部重点实验室,长沙410083 [2]中南大学地球科学与信息物理学院,长沙410083 [3]中国有色地质调查中心,北京100012

出　　处：《中国有色金属学报》2012年第3期733-742,共10页The Chinese Journal of Nonferrous Metals

基　　金：中国地质调查局项目(资[2008]青藏21-03);中国地质调查局项目(资[2011]03-01-64)

摘　　要：卡尔却卡多金属矿床位于祁漫塔格成矿带,矿区主要有斑岩型和矽卡岩型两种矿化类型,均与印支期花岗闪长岩关系密切。流体包裹体研究表明,矽卡岩矿石中可见水溶液包裹体(Ⅰ型);斑岩型矿化岩体中发育有水溶液包裹体(Ⅰ型)和含子矿物的包裹体(Ⅱ型)。斑岩型矿化岩体中的流体包裹体气液均一温度在274～495℃,盐度介于5.9%～59.1%(质量分数,NaCl equiv,下同)之间;矽卡岩矿石样品的气液均一温度集中在137～322℃,盐度介于0.7%～12.7%之间。研究显示矿区成矿流体来源于富Na+及成矿物质的高温(达500℃)、高盐度(达60%)的岩浆流体,具有超高压特征。流体演化至290～320℃时由于围岩碎裂减压而发生沸腾现象,并和外来流体混合,改变流体的成分和物理化学性质,有利于成矿物质沉淀富集。Abstract： There are two mineralization types in Kaerqueka copper polymetallic deposit in Qimantage area, Qinghai Province, which are skarn-type mineralization and porphyry-type mineralization. Both of the two mineralization types are closely related to Indosinian granodiorite. Fluid inclusions （FI） host in porphyry-type mineralization granodiorite and skarn-type ore, and the fluid inclusions in skam-type ore typically are aqueous FI （type I ） while those in porphyry-type mineralization granodiorite are usually aqueous FI （type I ） or daughter mineral-bearing FI （type II） as well. The homogenization temperatures of the fluid inclusions in the skarn-type ore and the porphyry-type mineralized granodiorite vary from 137℃ to 322℃ and 274℃ to 495℃, respectively. The salinities of skarn-type ore range from 0.7% to 12.7% （mass fraction, NaClcquiv）; and those in porphyry-type mineralized granodiorite range from 5.9% to 59.1%. The study demonstrates that the ore-forming fluids originate from magma which is high-temperature （up to 500℃）, hypersaline （up to 60%）, rich in Na＋ and metallogenic material, with the characteristics of ultrahigh pressure. Fluid-boiling occurs when the ore-forming temperatures are between 290℃ and 320℃ because of breaking of wall rocks. Then the composition and physicochemical properties of ore-forming fluids are changed by mixed extraneous fluids, leading to the precipitation and enrichment of metallogenie material.

关 键 词：斑岩型矿化 矽卡岩型矿化 流体包裹体 成矿流体 卡尔却卡 青海省 

分 类 号：P611.1[天文地球—矿床学]