摘要
在前人研究的基础上,通过系统的野外考察,论证了位于赣东北德兴地区德乐中生代火山盆地中的德兴铜矿、银山银铜铅锌矿和金山金矿及蛤蟆石金矿属于同一成矿系统。德兴铜矿是典型的斑岩铜矿,成矿流体和金属元素主要来自岩浆;银山银铜铅锌矿是一个下部为斑岩铜矿、上部为浅成低温热液型银铅锌矿,成矿流体早期以岩浆为主,晚期有较多的大气降水参与,成矿物质主要来自岩浆;金山和蛤蟆石金矿是远接触带热液矿床,成矿流体为岩浆热液与大气降水的混合产物,金主要来自围岩——双桥山群浅变质岩。这3套矿床以中酸性花岗斑岩或石英斑岩(高钾钙碱质花岗岩)为核心具有明显的分带性,自中心向外或深部向浅部为:斑岩铜金钼矿、浅成低温热液型银铅锌矿和远接触带热液型金矿。这种矿床组合关系不同于已知的经典斑岩铜矿模型和斑岩铜矿浅成低温热液金银矿床模型,因而,有必要提出一个新的模型:斑岩铜矿浅成低温热液银铅锌矿远接触带热液金矿模型。这套矿床形成于中侏罗世,抑或是古太平洋俯冲板片局部重熔或撕裂重熔的产物,抑或是在活动大陆边缘岩浆弧后伸展带由地幔底侵的结果。
Based on the previous studies and detailed field investigations in the Dexing porphyry Uu deposit, the Yinshan Ag-Pb Zn deposit and the Jinshan shear zone hosted Au deposit in the Dele Jurassic volcanic basin in the northeastern Jiangxi Province, East China are proposed to be same metallogenic system in this paper. The Dexing is a typical porphyry Cu-Au-Mo deposit in which both ore forming fluid and elements are derived from the granite porphyry. The Yinshan consists of porphyry Cu ore at the copular of quartz porphyry in the lower part and the vein type Ag Pb-Zn ore in the upper part. The hydrothermal fluid was mainly derived from the magma in the early stage and was incorporated with more meteoric water in the late stage, Its ore forming elements are mainly from the magma. The both Jinshan and the Hamashi, a quartz vein type gold deposit hosted by brittle fractures, are distal hydrothermal deposits, which were formed by mixed fluids of magmatic and meteoric water whereas the Au is mainly leached from the country rocks of Middle Proterozoic schists of the Shuangqiaoshan Group. These deposits spatially show a distinct zoning of porphyry Cu, epithermal Ag Pb-Zn and distal Au from the granite porphyry of quartz porphyry outside. In this case we suggest a new model entitled in porphyry-epithermal-distal system model for the group of mineral deposits with genetic relationship.
出处
《地球科学与环境学报》
CAS
2010年第1期1-14,共14页
Journal of Earth Sciences and Environment
基金
国家重点基础研究发展计划项目(2007CB411405
2007CB411407)
国家自然科学青年基金项目(40803008)
中国地质调查局项目(1212010634001)
