浏阳市井冲钴铜多金属矿床地质特征及成因浅析

Geological Characteristics and Genesis of Jinchong Co-Cu Polymetal Deposit,Liuyan,Hunan Province

浏阳井冲钴铜多金属矿床位于钦杭断裂带西段湘东北铜金成矿带之长平断裂带中部。矿区勘查工作时间跨度达50年,2008年工作程度达到详查,探求钴铜资源量达中型矿床规模。钴铜多金属矿成矿与长平断裂带和燕山期连云山花岗岩、花岗闪长斑岩有关。矿体产于长平断裂带次级构造热液蚀变岩带中,中泥盆统碎屑岩和灰岩透镜体对成矿有利。矿体沿构造热液蚀变岩带向SW向有明显侧伏趋势,矿化垂向分带明显,表现为深部钴铜矿,浅部铅锌矿。构造找矿标志、岩浆岩找矿标志、金属量铅异常找矿标志、磁异常找矿标志、原生晕异常找矿标志、围岩蚀变找矿标志和直接矿化找矿标志明显。综合成矿物质来源、成矿条件等研究资料,初步确定本矿床属于与花岗岩有关的中温热液裂隙充填交代型钴铜多金属矿床。

Jingchong Co-Cu polymetallic deposit is located at the middle of Changping fault zone,which is part of northeastern Hunan province Cu-Au metallogenic belt in west part of Qinzhou-Hangzhou tectonic block.The exploration work in this deposit is lasting for fifty years until medium-sized Co-Cu deposit are found in 2008.The formation of Co-Cu ore-bodies is closely related to the movement of Changping fault zone and intrusion of Yanshanian Lianyunshan granite and granodiorite porphyry,and the favorable space for ore-bodies are structural hydrothermal altered zone and clastic rock（or limestone lenticle）of Middle Devonian.The ore-bodies are pitched to SW along structural hydrothermal altered zone,whose main ore-type is subdivided into Co-Cu ore in the deep,and Pb-Zn ore in the superficial part.The source of ore-forming materials and mineralization condition are indicated that Jingchong Co-Cu polymetallic deposit is an mesothermal fissure-metasomatic-filling deposit.The prospecting indicator of structure,magmatic rocks,Pb metal anomaly,magnetic anomaly,primary halo,and wallrock alteration are summarized for prospecting for the similar in the area in the future.