EH4音频大地电磁测深方法在鄂东南地区寻找隐伏矿体的应用  

Application of the Audio-Frequency Magnetotelluric Method to Search for Concealed Ore bodies in Southeastern Hubei Province

作　　者：谭红艳[1,2] 吕骏超[2] 刘桂香[2] 马诗敏[2] 舒广龙[2] 席振铢[3] 

机构地区：[1]中国地质大学,北京100083 [2]沈阳地质调查中心,辽宁沈阳110034 [3]中南大学,湖南长沙410083

出　　处：《地质与勘探》2011年第6期1133-1141,共9页Geology and Exploration

基　　金：中国地质调查局国土资源大调查项目(1212010881201)资助

摘　　要：鄂东南丰山矿田是长江中下游成矿带重要的铜金矿田,可采资源储备严重不足,亟待寻找接续资源。新一轮找矿主要是寻找隐伏矿体,这不仅需要准确圈定找矿靶区,更离不开物探技术方法的合理应用。在研究以往工作成果的基础上,选择丰山南山作为找矿靶区,首次应用音频大地电磁测深(EH4),并辅以双频激电测深和地质剖面测量方法进行定位预测。EH4采用连续剖面测深方法,网度为100m×20m,采用天然源,采集频率范围为10Hz～100kHz。对采集的数据进行二维反演和二维电磁成像,经综合分析确定找矿靶位。钻探验证7线物探异常,发现隐伏铜金工业富矿体,实现深边部找矿突破。研究表明,在危机矿山应用EH4寻找隐伏矿体具有广阔的前景。The Fengshan deposit in southeastern Hubei Province is an important Cu-Au ore-field in tile metallogenic belt of the middle and lower reaches of the Yangtze River. It has, however, a serious lack of the mineral resources reserves and urgent need to search for new deposits. Concealed ore bodies will be the primary prospecting targets, which require reasonable usage of geophysical techniques. Based on previous work, audio-frequency magnetotelluric sounding （EH4） was applied for the first time to locate and forecast the south of Fengshan as a target area in combination with electro-prospecting sounding and geological profile measurements. The EH4 used a continuous profile sounding method to collect data of frequency ranging from 10 Hz to 100 kHz with a network of density 100×20m. Then the collected data was processed by two-dimensional inversion and electromagnetic imaging, and the target was determined by integrated analysis. Drilling verified geophysical anomalies on line No. 7 and found concealed copper and gold ore bodies, which achieved a breakthrough in prospecting toward depth and sides. The study shows that the application of the EH4 to explore concealed orebodies of crisis mines has a broad prospect.

关 键 词：EH4 隐伏矿体 丰山铜金矿田 鄂东南 

分 类 号：P631.3[天文地球—地质矿产勘探]