河南康山金矿同位素地球化学及其对成岩成矿及流体作用模式的印证  

Isotope Geochemistry of the Kangshan Gold Deposit in Henan and Its Illustration of the CPMF Model

作　　者：王海华[1,2] 陈衍景[1,2] 高秀丽[1,2] 

机构地区：[1]北京大学地质学系 [2]南京大学内生矿床国家重点实验室,南京210093

出　　处：《矿床地质》2001年第2期190-198,共9页Mineral Deposits

基　　金：国家攀登预选课题(编号;95-预-39-04);!自然科学基金(编号:49972035);南京大学内生矿床国家重点实验室项目

摘　　要：康山金矿位于华北克拉通南缘熊耳山区，矿化类型介于蚀变破碎带型与石英脉型矿床之间，为硅化体型金矿。蚀变矿化过程分为早期石英一黄铁矿阶段、中期多金属硫化物阶段和晚期碳酸盐阶段；温度分别集中在３００～３８０℃、１８０～２４０℃和１００～１４０℃；碳氢氧同位素研究揭示成矿流体由变质热液经混合热液，向大气降水热液演化。流体混合导致矿化中期成矿物质快速沉淀，多金属硫化物等多种矿物爆发形成，且结晶程度低（以玉髓和烟灰状黄铁矿为标志），含矿性好，是大规模成矿的关键。碳铅硫同位素研究表明成矿物质主要来自马超营断裂南侧由官道口群、栾川群、太华超群等地层构成的俯冲板片，而赋矿围岩熊耳群提供成矿物质的可能性最小，因此认为中生代时沿马超营断裂倾向北的陆内俯冲诱发了流体成矿作用，导致康山金矿等熊耳山区１０多处大中型矿床的形成和规律性分带，马超营断裂北侧是寻找金、银等矿床的有利地带。本文印证了同碰撞矿床的存在和成岩成矿及流体作用（ＣＰＭＦ）模式。Located in the Xionger terrain along the southern margin of the North China craton, the Kangshan gold deposit is assigned to metasomatic quartzite type between the typical quartz-vein type and the altered fracture type. The a iteration- mineralization process mighi be divided into t he early stlicificanon-pyritization stage, the middle polymetallic sulfidization stage and the late carbonation stage, with temperatures ranging 300 - 380, 180-240 and 100 - 140, respectively. A study of C-D-O isotope system shows that the ore fluids changed from early metamorphic, through middle hybrid to late meteoric solutions. The middle stage fluid hybridization, resulting in rapid precipitation of ore materials and sudden formation of numerous kinds of minerals such as polymetallic sulfides and leading to poor crystallization (marked by ash-like pyrite and chalcedony) and high gold content of minerals, was the key to the large-scale metallogenesis. The C-S-Ph isotpic studies have revealed that the ore material was mainly derived from the subducted slab south of Machaoying fault, which was made up of the Guandaokou Group, Luanchuan Group, Taihua Supergroup, etc.. On the contrary, the Xionger Group, as the host rocks, is unlikely to have provided significant ore materials for the formation of the Kangshan gold deposit. Hence the Mesozoic northward intracontinental subduction along Machaoying fault induced fluidization and mineralization, resulting in the formation and the zonal distribution of more than ten large or medium gold/ silver deposits such as the Kangshan deposit in the Xionger terrain. The northern side of Machaoying fault seem to be the favorable place for gold, silver and lead prospecting. This study gives an example of syn-collision deposit and demonstrates the scientificalness of the CPMF (collisional petrogenesis, metallogenesis and fluidization) model.

关 键 词：秦岭造山带 同位素 成矿流体 成矿物质 金矿床 CPMF模式 地球化学 流体作用模式 

分 类 号：P618.51[天文地球—矿床学] P597[天文地球—地质学]