云南省保山西邑铅锌矿区地电化学方法找矿预测研究

Application study of geoelectro-chemical method for prospecting work and prediction of Xiyi Pb-Zn deposit in Baoshan City of Yunnan

云南西邑铅锌矿区位于三江成矿带中南段,怒江断裂与澜沧江断裂之间,以柯街断裂为界的保山地块中,属于典型SEDEX型矿床。结合野外地质调查,运用地电化学技术在矿区外围寻找隐伏铅锌矿。通过研究获得如下成果:①地电化学技术在该区寻找类似的隐伏铅锌矿是合理有效的;②以地电提取主成矿元素Pb、Zn异常衬度大、浓度分带清晰、明显,与Ag、Ge等伴生元素的异常衬度成正相关,吻合度较高,作为研究区内地电化学技术找矿指标;③根据元素异常分布特征、异常空间位置及可靠程度分析,结合地质情况,共圈定4个找矿靶区,其中Ⅰ类靶区1个,Ⅱ类靶区2个,Ⅲ类靶区1个,建议将Ⅰ类靶区作为下一步工作的重点。

Xiyi Pb-Zn deposit is located at the Baoshan block,between Lancang fault and Nujiang fault,in the south section of Sanjiang metallogenic belt in Yunnan Province.The deposit belongs to the typical SEDEX type.On the basis of field geological survey,geoelectro-chemical technology is used to search for hidden Pb-Zn orebodies in the periphery of mining area.The study result is shown as follows.(1)The geoelectro-chemical method is reasonable and effective to explore for the concealed Pb-Zn orebody in the mining area.(2)The anomaly contrast of Pb-Zn is large and the concentration zone is clear and obvious for the main ore-forming elements,which are closely relative to the anomalies of Ag-Ge in a high degree of agreement.They can be taken as the indicators of geoelectro-chemical technology to explore for the concealed orebody in the area.(3)According to the distribution characteristics of element anomalies,spatial location of anomalies and analysis of reliability,and the geological condition,four target areas are delineated,including one target area of type I,two target areas of type II and one target area of typeⅢ.It is suggested that the target area of type I should be the focus of the prospecting work in the future.