覆盖区矿产勘查中电法技术应用及有效性探讨  

Discussion on Application and Effectiveness of Electrical Method in Mineral Exploration in Covered Areas

作　　者：苏文利[1,2] 陆桂福 刘福胜[3] 段壮 付燕刚 SU Wenli;LU Guifu;LIU Fusheng;DUAN Zhuang;FU Yangang(Institute of Geophysical and Geochemical Exploration,Chines Academy of Geological Sciences,Langfang,Hebei 065000;National Center for Geological Exploration Technology,Langfang,Hebei 065000;China Coal Geology Group Co.Ltd.,Beijing 100040)

机构地区：[1]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000 [2]国家现代地质勘查工程技术研究中心,河北廊坊065000 [3]中煤地质集团有限公司,北京100040

出　　处：《中国煤炭地质》2023年第11期72-76,共5页Coal Geology of China

基　　金：中国地质调查局地质调查三级项目“新疆东天山等重点成矿区带浅覆盖区铜镍多金属矿调查”(DD20230309)。

摘　　要：香林香达铜矿床位于内蒙古苏尼特右旗境内,属于华北板块北缘多金属成矿带的一部分。区内覆盖较厚,为草原景观区,地表露头较少,地质填图和化探方法难以满足勘查需求。本次在探矿权范围内,通过大比例尺激电中梯面积测量圈定了两处激电异常(1km2),有效缩小了找矿靶区范围。结合可控源音频大地电磁测深精测剖面对激电中梯异常部位进行剖析,圈定了地下极化异常体的空间位置。经钻探验证激电异常为矿致异常,见矿总厚度15m,铜的最高品位3.14%,平均品位1.21%。确定了本区可控源音频大地电磁测深反演剖面高阻异常的边缘部位,构造带低阻异常区内相对高阻异常部位为矿体位置,证实了激电中梯面积测量配合频率域电磁法在覆盖区内金属矿勘查中得有效性,相关研究成果为该类覆盖区找矿提供参考依据。Xianglinxiangda copper mine is located in Sunite Right Banner,Inner Mongolia.It belongs to a part of polymetallic metallogenic belt on the northern margin of North China Plate.It is a grassland landscape area with thick coverage and few outcrops.It is difficult for geological mapping and geochemical exploration methods to meet the exploration needs.Two IP anomalies(1km2)were delineated by measuring the IP middle ladder area of large scale within the scope of prospecting right,effectively narrowing the scope of prospecting target area.Combined with the fine profile of controlled source audio magnetotelluric sounding,the abnormal part of IP elevator is analyzed and the spatial location of underground polarizing abnormal body is delineated.The IP anomaly was verified by drilling as ore-induced anomaly,the total thickness of the ore was 15m,the highest grade of copper was 3.14%,and the average grade of copper was 1.21%.The edge part of high resistivity anomaly in the inversion profile of controlled source audio magnetotelluric sounding and the relatively high resistivity anomaly part in the low resistivity anomaly area of the structural belt are identified as the ore body location,which proves the effectiveness of IP middle step area measurement combined with frequency domain electromagnetic method in metal ore exploration in the covered area.This research results provide a reference basis for prospecting in this type of covered area.

关 键 词：大功率激电 可控源音频大地电磁测深 覆盖区勘查 找矿效果 

分 类 号：P631.3[天文地球—地质矿产勘探]