多种电磁测深技术在深部控矿构造探测中的应用研究——以泥河铁矿为例  

Application of Comprehensive Magnetotelluric Sounding Technique in Prospecting Deep Structures:A Case Study of Nihe Porphyrite Iron Deposit

作　　者：匡海阳[1] 吕庆田[1,2] 张昆[2] 严加永[2] 陈向斌[2] 

机构地区：[1]东华理工大学核工程技术学院,江西抚州344000 [2]中国地质科学院矿产资源研究所,国土资源部成矿作用与资源评价重点实验室,北京100037

出　　处：《地质学报》2012年第6期948-960,共13页Acta Geologica Sinica

基　　金：国家科技专项"深部矿产资源立体探测技术与实验"(编号SinoProbe-03);国家自然科学基金重点基金项目"长江中下游成矿带深部动力学与成矿作用研究"(编号40930418);地质调查项目"长江中下游地区地壳精细结构与控矿研究"(编号1212010981004);科技支撑计划项目"玢岩型铁(硫)矿深部勘查技术与找矿示范研究"(编号2009BAB43B02)联合资助的成果

摘　　要：长江中下游成矿带是我国东部重要的铁、铜多金属矿产资源基地,使用现代地球物理探测技术对该成矿带典型矿床深部结构进行探测,对认识深部矿床成因、总结找矿方法和深部找矿的实践具有重要意义。本文选取位于长江中下游成矿带庐枞矿集区内的泥河玢岩铁矿为实验区,开展了音频大地电磁(AMT)、可控源音频大地电磁(CSAMT)和瞬变电磁(TEM)等电磁法探测实验;通过对AMT、CSAMT和TEM数据的处理和反演,发现3者相同测线反演结果反映的控矿地质体电性特征基本一致,但细节上存在一定差异。综合3种电磁测深反演结果,电性特征刻画了砖桥组火山岩地层分布,分辨出闪长玢岩体的隆起部位和基本形态,揭示了矿体的赋存位置。认为在合理的数据采集、处理和反演条件下,电磁测深能有效地区分复杂地质构造条件下次火山岩与围岩的电性差异,找到控矿构造界面,从而推断出矿体的位置。Middle-Lower Yangtze Valley is an important base of poly-metallic mineral deposits in eastern China.Advanced geophysical survey was employed to prospect the deep structures in typical deposits,and this is of great significance in understanding the genesis of the deep deposits and summarizing exploration methods.In this paper,we chose the Nihe porphyrite iron ore in the Luzong district,Anhui province,as a trial site.Audio magnetotelluric（AMT） sounding,controlled source audio magnetotelluric（CSAMT） sounding and transient electromagnetic（TEM） sounding were carried out.Through the processing and inversion of AMT,CSAMT and TEM data,it is discovered that ore-controlling geological bodies are basically similar in electrical characters but different in some details.The results of three methods,and electrical characters determined distribution of the Zhuanqiao Formation volcanic rock,and identified positions and shape of diorite porphyrite,and inferred the position of ore bodies.Out study suggests that under the condition of processing and reversion of reasonable data,magnetotelluric sounding can distinguish the difference of electrical characters between subvolcanic rock and wall rock to effectively position the interface of ore-controlling structures and thus to infer the positions of ore-bodies.

关 键 词：玢岩铁矿 泥河 深部找矿 AMT CSAMT TEM 

分 类 号：P631.325[天文地球—地质矿产勘探]