江西城门山铜矿床伴生稀散金属矿化特征及其地质意义北大核心CSCD

江西城门山铜矿床通过开展深边部找矿勘查,发现其探明的伴生稀散金属资源量达到大型甚至超大型规模,其中碲、铊、镉、硒等稀散金属已综合回收利用,但研究程度还很低。本文收集整理城门山矿床的编录及化验资料,总结该矿床稀散金属的矿化特征和空间分布规律,并探讨稀散金属富集机理和控制因素。结果表明,城门山矿床的稀散元素多倾向于富集在似层状硫化物型矿石中,赋存状态以独立稀散金属矿物和赋存于黄铁矿、黄铜矿和闪锌矿等硫化物晶格为主,具有随金属硫化物总量变化而变化的空间分带特征。矿石中的w(Cd)与w(Zn)具明显的正相关性(R^(2)=0.65),其他稀散元素的含量与Cu多呈弱正相关性。本文提出碲与铊与似层状硫化物矿石密切相关,镉的超常富集主要与锌的成矿作用有关,它们在热液流体萃取、运移、沉淀过程中元素分离相对较少,岩浆结晶分异导致热液流体中铟含量降低,铼主要赋存在辉钼矿中,与幔源物质参与密切相关。同时,还建立了城门山含稀散金属铜矿床的成矿模式。

Mineralization of associated dispersed elements in the Chengmenshan copper deposit of Jiangxi Province and its geological significance

The Chengmengshan deposit in Jiangxi Province is an important part of the middle-lower Yangtze River Belt, which has been intensively explored in recent years. This deposit has reserves of main metals such as copper, zinc, lead and silver, and also contains associated dispersed elements with a large or superlarge scale. The dispersed elements of tellurium, thallium, cadmium and selenium have been comprehensively recycled, but have been little documented. Based on previous drilling logging and testing data, this work analyzed the mineralization and distribution rules of the dispersed elements, and discussed the enrichment mechanism and controlling factors for this deposit. The dispersed elements of the Chengmengshan deposit tend to be enriched in layered sulfide-type ores, and mainly occur in independent rare metal minerals or sulfide lattice of pyrite, chalcopyrite and sphalerite. The contents of dispersed elements vary with the content of metal sulfides. The Cd content in the ores correlates well with that of Zn content (R2=0.65), and other dispersed contents are weakly positively correlated with Cu content. Tellurium and thallium are closely related to layered sulfide ores. The extraordinary enrichment of cadmium is mainly related to zinc mineralization. They have been relatively less separated in the process of hydrothermal fluid extraction, migration and precipitation. Magmatic crystallization differentiation led to the reduction of indium content in hydrothermal fluids, and rhenium is mainly hosted in molybdenite, which is closely related to the participation of mantle-derived materials. This work also established the metallogenic model of the Chengmenshan dispersed element-bearing copper deposit.