音频大地电磁法在黔西南金矿区域地电特征研究中的应用  

Application of Audio Geomagnetic Method in the Study of Regional Geoelectric Characteristics of Gold Deposits in Southwestern Guizhou

作　　者：王家俊 杨炳南[1,2,3] 朱大伟 韩姚飞[1,2] 张德实 Wang Jiajun;Yang Bingnan;Zhu Dawei;Han Yaofei;Zhang Deshi(Engineering Technology Research Center of Geology and Geophysics Development and Application of Guizhou Province,Ministry of Natural Resources,Guiyang Guizhou 550081,China;No.103 Geological Party,Bureau of Geology and Mineral Exploration and Development of Guizhou Province,Tongren Guizhou 554300,China;College of Resources and Environmental Engineering,Guizhou University,Guiyang Guizhou 550025,China)

机构地区：[1]自然资源部基岩区矿产资源勘查工程技术创新中心,贵州贵阳550081 [2]贵州省地质矿产勘查开发局一〇三地质大队,贵州铜仁554300 [3]贵州大学资源与环境工程学院,贵州贵阳550025

出　　处：《工程地球物理学报》2024年第4期611-620,共10页Chinese Journal of Engineering Geophysics

基　　金：贵州省地质矿产勘查开发局地质科研项目(编号:黔地矿科合(2018)10号);贵州省地矿局科技创新人才团队培育计划项目(编号:黔地矿科合(2023)TD001)。

摘　　要：黔西南地区是我国重要的卡林型金矿分布区,区内台地和盆地沉积格局交替频繁,金矿成矿主要受褶皱和断裂构造控制,查明该区地层分布及构造展布特征对于该区金矿找矿具有重要意义。本文以黔西南金矿区为研究靶区,分别进行了音频大地电磁法(Audio Magnetotelluric Method,AMT)在台地相、盆地相不同模式的正反演计算,基于优选的反演模式在区内实地开展了音频大地电磁法的应用研究,取得主要结果与认识:①台地相区地层电性差异明显,基于TE&TM联合反演模式的AMT能有效区分地层、查明断裂构造空间展布特征;②受上部厚低阻层影响,AMT在盆地相区地层区分性弱,基于TM反演模式的AMT能清晰反映褶皱、断裂构造空间展布特征;③黔西南金矿区域地质条件复杂,因地制宜的优选AMT反演模式是实现该区地电结构精细刻画的关键。研究成果与区内实测断层、钻探工程等验证结果吻合较好,充分体现了AMT在该区查明地层分布及构造展布特征的有效性;另一方面进一步明确了黔西南金矿区域台地相、盆地相AMT反演模式,对后人利用AMT在该区及相近地区实现金矿找矿突破具有重要的参考价值。The southwestern Guizhou area is an important distribution area of Carlin-type gold deposits in China.The sedimentary pattern of the platform and basin in the area alternates frequently.The gold mineralization is mainly controlled by folds and faults.It is of great significance to find out the stratigraphic distribution and structural distribution characteristics of the area for gold prospecting in this area.In this paper,the gold mining area in southwest Guizhou is taken as the research target area,and the forward and inversion calculation of audio magnetotelluric method(AMT)in different models of platform facies and basin facies is carried out respectively.Based on the optimized inversion model,the application of audio magnetotelluric method is carried out in the target area.The main results and understandings are as follows:①The stratigraphic electrical differences in the terrace phase area are obvious,and AMT based on the TE&TM joint inversion model can effectively distinguish the stratigraphy and identify the spatial spreading characteristics of the fracture tectonics;②AMT is weakly differentiated in the stratigraphy of the basin phase area due to the influence of the upper thick low-resistance layer,and AMT based on the TM inversion model can clearly reflect the spatial spreading characteristics of folded and fractured tectonics;③The regional geological conditions of gold deposits in southwestern Guizhou are complex,and the optimal AMT inversion model according to local conditions is the key to realize the fine characterization of geoelectric structure in this area.The research results are in good agreement with the verification results of the measured faults and drilling projects in the area,which fully reflects the effectiveness of AMT in identifying the stratigraphic distribution and structural distribution characteristics in this area.On the other hand,the AMT inversion model of platform facies and basin facies in the gold deposit area of southwestern Guizhou is further clarified,which has importa

关 键 词：音频大地电磁法 反演模式 地电特征 黔西南金矿区 

分 类 号：P631.3[天文地球—地质矿产勘探]