宁芜北火山岩覆盖区时间域激电三维反演及找矿预测——以吴庄工区为例  

Time-domain IP 3D inversion and ore-prospecting prediction of volcanic rock coverage area in the northern Nanjing-Wuhu area:A case study of the Wuzhuang work area

作　　者：张景[1] 朱红兵[1] 邸兵叶[1] 鲁胜梅[1] ZHANG Jing;ZHU Hong-bing;DI Bing-ye;LU Sheng-mei(Nanjing Center,China Geological Survey,Nanjing 210016,China)

机构地区：[1]中国地质调查局南京地质调查中心,南京210016

出　　处：《华东地质》2018年第2期126-133,共8页East China Geology

基　　金：国家重大科学仪器设备开发专项"大深度三维电磁探测技术工程化开发(编号:2011YQ050060)"项目资助

摘　　要：宁芜地区是长江中下游成矿带铁铜多金属矿床最有利的成矿区之一,该区工作程度较高,已发现多处铁铜多金属矿床,但近年来找矿进展缓慢,如何在宁芜火山岩覆盖区实现找矿突破是目前研究的重点和热点。前人多采用时间域激电一维和二维反演技术进行资料处理和异常解释,因时间域激电三维反演技术对硬件要求较高,较少在实际中应用。在综合分析工作区区域地质资料、对典型地层和岩石标本进行物性参数测试和统计分析的基础上,采用T 30多功能电磁法发射机和EM-R06多功能电磁法接收机在吴庄工区开展时间域激电(TDIP)测量,利用EM3DSPI软件对野外实测数据进行三维反演。结果表明:工作区岩体大多呈岩株或岩脉侵入于大王山组火山岩中,具有以NE向断裂为主、NW向断裂穿插分布的特征。结合周边矿区和已施工钻孔资料,确定吴庄工区王家场为成矿有利区域,该区值得进一步开展地质调查工作。The Nanjing-Wuhu area is one of the most favorable iron-copper polymetallic areas in the Middle and Lower Yangtze metallogenic belt.High extent of exploration in this area has led to discovery of several iron and copper polymetallic deposits.However,prospecting progress has been slow in recent years.Therefore,how to make prospecting breakthrough in the Nanjing-Wuhu volcanic rock covered area has thus become a research focus and hot spot.Previous researchers employed only one-dimensional and two-dimensional time domain inversion technique to process data and interpret anomalies.Three-dimensional inversion technique has not been put into practice due to its high hardware requirements.Based on regional geological data of the work area,as well as parameter measurement and statistical analysis of physical properties of typical formations and rock specimen,time domain induced polarization（TDIP）measurement in the Wuzhuang working area was conducted using a T30 electromagnetic transmitter and an EM-R06 multi-functional electromagnetic receiver,and three-dimensional inversion of field data was performed with EM3 DSPI software.Three dimensional inversion results indicate that the rock masses in the work area intruded into the volcanic rock formation of Dawangshan Formation as stocks and dykes,characterized by dominant NE-trending faults interspersed by minor NW-trending faults.Combined with mining information in surrounding areas and existing drilling data,it can be considered that Wangjiachang at the Wuzhuang work area should be favorable area for mineralization and worthy of further deployment.

关 键 词：覆盖区 时间域激电 三维反演 找矿预测 长江中下游成矿带 

分 类 号：P631.14[天文地球—地质矿产勘探]