广东圆珠顶斑岩型铜钼矿床成矿物质、成矿流体来源和成矿机理研究  

Source of metallogenic materials and ore-forming fluids,and metallogenic mechanism of the Yuanzhuding porphyry Cu-Mo deposit,western Guangdong Province,South China

作　　者：楚克磊[1] 毛景文[1] 陈懋弘[1] 赵军[2] 余长发[3] 林良庄[4] 林秀广[4] 

机构地区：[1]中国地质科学院矿产资源研究所,北京100037 [2]长安大学地球科学与资源学院,陕西西安710054 [3]中国地质大学(北京)地球科学与资源学院,北京100083 [4]广东省地质勘查局719地质大队,广东肇庆526020

出　　处：《地学前缘》2013年第5期115-125,共11页Earth Science Frontiers

基　　金：国家重点基础研究发展计划'973'项目(2012CB416704);中国地质调查局工作项目(1212011120831)

摘　　要：圆珠顶斑岩型铜钼矿床位于钦杭成矿带西南端，是该成矿带近年来发现的又一大型铜钼矿床。文中通过对圆珠顶矿床地质特征的详细剖析并结合H、O、S、Pb等同住素地球化学的研究，对圆珠顶斑岩型铜钼矿床的成矿流体和成矿物质来源进行了初步的讨论。研究结果表明：矿石金属硫化物δ34 S值分布于4．3‰～3．9‰，硫主要来源于岩浆岩；矿石铅同位素组成稳定，为正常普通铅；不同成矿阶段H、O同位素组成变化及流体包裹体研究指示大气降水与含矿岩浆热液混合是金属矿物从成矿流体中沉淀的重要因素。结合成矿动力学背景研究，认为圆珠顶矿床成矿作用与岩浆活动密切相关，矿床成因是由于板块俯冲作用引起的地壳与地幔物质混合。The Yuanzhuding CuMo porphyry deposit, located at the southwest of the Qin-Hang Neoproterozoic suture, is a newly discovered large-scale CuMo deposit in the metallogenic belt. Based on a detailed analysis of geological characteristics and a study of H, O, S, and Pb isotopic geochemistry, the features of fluid evolution and the origin of the ore-forming fluid of the deposit has been discussed preliminarily in this paper. The results show that the sulfur came mainly from the ore-forming magma and the δ34 S values of sulfide in the ore distributed in a range between 4. 3%-3. 9%. The ore has a stable isotopic composition composed of common lead. Considering the Metallogenic geodynamics background, the Yuanzhuding deposit mineralization was closely related to a magmatic activity, and was originated from the mixing of the crust and mantle material triggered by the subduction. According to the alteration of H and O isotope composition in different ore-forming stage and the existing fluid inclusion studies, it is suggested that the mixing between meteoric water and the hydrothermal fluid of ore-bearing magma is the key factor that caused the Yuanzhuding metallic minerals precipitated out of the ore-forming fluids.

关 键 词：圆珠顶 斑岩铜钼矿床 同位素组成 成矿物质来源 金属沉淀机制 

分 类 号：P618.41[天文地球—矿床学] P618.65[天文地球—地质学]