江西万载县兴源冲铜矿成矿地质特征及矿床成因探讨

摘 要]江西兴源冲铜矿是近几年发现的具有较大潜力的铜多金属矿床,所处的黄茅地区属九岭南缘多层次大型构造叠加成矿地质背景的西段。在野外详细的地质考察以及室内岩矿鉴定的基础上,运用电子探针和气体同位素质谱仪以及包体测温等现代分析测试技术,对兴源冲铜多金属矿床的成矿地质特征及其矿床成因进行了深入细致的分析研究。实验分析得出:电子探针分析数据表明矿石中含大量Cu、Fe,少量Zn、Au,其中Cu 含量达工业品位;矿石中δ³⁴ S_CDT值和包裹体盐度值说明其成矿流体具有同源性,可能来源于地幔或者与岩浆同源;包体均一温度有两个峰值区间,说明矿床受二期成矿流体控制。综合区域、矿区地质特征、矿体特征以及上述实验所得,得出该矿床应为海相-火山喷流沉积变质叠改型铜矿床。

Geological Features and Genesis of the Xingyuanchong Copper Deposit in Wanzai County, Jiangxi Province

The Xingyuanchong copper deposit in Jiangxi Province is a recently discovered copper-polymetallic deposit with great potential.It is located in the Huangmao area,which belongs to the western section of the multiple-layer large-scale structure in the southern edge of the Jiuling area.Based on regional geological surveys,identification of rocks and ores,application of the EMPA,IRMS methods and inclusion temperatures,this paper carries out a detailed analysis of the geological features and genesis of the Xingyuanchong copper deposit.The EMPA data show that the ores contain a large amount of Cu and Fe and a small amount of Zn and Au,and the Cu content reaches the industrial grade.Values of δ34SCDT and salinity in inclusions indicate the metallogenic fluids have the same source,probably originated from the mantle or have the same source with magma.The two distribution ranges of the fluid homotemperatures show this deposit was controlled by two-phase metallogenic fluids.Integrating the geological features of the region and the ore district,orebody characters and analysis aforementioned,this paper comes to the conclusion that this deposit is of the superposition-reform type associated with marine volcanic exhalation and metamorphic sediments.