粤西元湾金矿地质特征及找矿标志

Geological characteristics and prospecting criteria of yuanwan gold deposit in western guangdong

元湾金矿床位于钦杭成矿带南端,具有较好的成矿地质条件。结合近年地质勘查成果,分析矿床地质特征,从地层、蚀变特征、构造、地球物理异常、地球化学异常等方面提出矿床的找矿标志。研究表明:(1)元湾金矿赋存于寒武系牛角河组浅变质岩中,主要受NW、NNE-NE向断裂控制,属于中低温热液型金矿床;(2)牛角河组浅变质岩是矿区成矿物质的主要来源,广宁-罗定断裂和岩浆侵入作用是矿床重要的成矿条件;(3)黑云二长花岗岩δEu值为0.01~0.24,属华南燕山期重熔岩浆成因的花岗岩类.

The yuanwan gold deposit is located in the southern of qinzhou-hangzhou metallogenic belt and has good metallogenic geological conditions.Based on the research results of geological exploration in recent years,the geological characteristics of the deposit are analyzed,and prospecting indicators for the deposit are proposed from aspects such as stratum,alteration characteristics,structure,geophysical anomalies,and geochemical anomalies.The research shows that:①The yuanwan gold deposit occurs in the shallow metamorphic rock of Cambrian niujiaohe formation,which is mainly controlled by NW and NNE-NE faults,and belongs to medium low temperature hydrothermal gold deposit;②The shallow metamorphic rocks of niujiaohe formation are the main source of ore-forming materials in the mining area.The Guangning-Luoding fault and magmatic intrusion are important metallogenic conditions of the deposit;③The δEu value of biotite monzogranite is 0.01~0.24,belonging to the granite of Yanshanian remelting magma in South China.