广域电磁法在北秦岭蟒岭矿集区深部找矿中的应用——以腰庄矿区为例  

Application of wide-field electromagnetic sounding method to deep prospecting in the Mangling ore concentration area in North Qinling:A case study of the Yaozhuang ore district

作　　者：张晓团 李新林 周斌 高维强 ZHANG Xiao-Tuan;LI Xin-Lin;ZHOU Bin;GAO Wei-Qiang(Shaanxi Institute of Geological Survey,Xi'an 710004,China;Shaanxi Geological Survey Planning Research Center,Xi'an 710068,China;School of Earth Science and Resources,China University of Geosciences,Beijing 100083,China)

机构地区：[1]陕西省地质调查院,陕西西安710004 [2]陕西省地质调查规划研究中心,陕西西安710068 [3]中国地质大学(北京)地球科学与资源学院,北京100083

出　　处：《物探与化探》2024年第6期1609-1617,共9页Geophysical and Geochemical Exploration

基　　金：陕西省地质勘查基金项目(61201908334);陕西省公益性地质调查项目(202112;202308)。

摘　　要：蟒岭矿集区岩浆活动强烈,是近年来北秦岭构造带深部找矿的热点地区,区内钼矿的形成与晚侏罗世酸性小岩体关系密切。为实现该区深部找矿突破,本文在重力异常圈定的腰庄隐伏岩体上开展了广域电磁法测量。测量结果显示,深部存在明显的高阻异常,推断高阻异常的凸起部位为腰庄隐伏岩体;其电阻率反演结果基本刻画了该岩体的顶面变化特征,推断顶面海拔介于-300~620 m、南北宽度1300~1600 m。通过对优选出的深部成矿有利部位进行钻探验证,揭示了隐伏岩体和隐伏钼矿体的存在。结果表明,广域电磁法探测深度大、分辨率高,是蟒岭矿集区深部找矿的有效勘查方法。The Mangling ore concentration area with intense magmatic activity has become a focal area for deep prospecting in the North Qinling tectonic belt in recent years.The formation of molybdenum deposits in this area is closely related to small Late Jurassic acidic intrusions.To achieve breakthroughs in deep ore prospection within this area,this study conducted the wide-field electromagnetic sounding over the concealed Yaozhuang intrusion delineated based on gravity anomalies.The results indicate the presence of pronounced high-resistivity anomalies at depth,and it is inferred that the protruding part of the anomalies corresponds to the concealed Yaozhuang intrusion.The resistivity inversion results roughly delineated the variations in the top surface of the intrusion,with the elevations and N-Swidth of the top surface estimated at-300-620 m and 1300~1600 m,respectively.Drilling in the most favorable deep mineralized part confirmed the presence of the concealed intrusion and concealed molybdenum ore bodies.The results of this study demonstrate that the wide-field electromagnetic sounding method exhibits great sounding depths and high resolutions,serving as an effective method for deep ore prospecting in the Mangling ore concentration area.

关 键 词：广域电磁法 深部找矿 蟒岭矿集区 北秦岭 钼矿体 

分 类 号：P631[天文地球—地质矿产勘探]