高精度磁测找矿效果——以青海尕林格矿区为例  

THE EFFECTS OF APPLYING HIGH-PRECISION MAGNETIC SURVEY:A CASE STUDY OF THE GALINGE ORE DISTRICT IN QINGHAI PROVINCE

作　　者：张恒磊[1] 刘天佑[1] 朱朝吉 周肇武 

机构地区：[1]中国地质大学地球物理与空间信息学院,湖北武汉430074 [2]青海省有色矿产勘查院,青海西宁810007

出　　处：《物探与化探》2011年第1期12-16,共5页Geophysical and Geochemical Exploration

基　　金：全国危机矿山接替资源找矿项目(200799084);青海省科技厅资助科研项目(2009-G-118-02)联合资助

摘　　要：青海尕林格铁矿区地表有近200 m厚的第四系覆盖层,地质工作几乎无法开展,加之钻井控制有限,增加了该区勘探的难度。笔者在前人工作的基础上,运用小波多尺度方法分析了该区的平面磁异常,发现小波一阶、二阶细节突出了3线附近的断裂特征,同时对3线设计剖面作正演计算,也表明该剖面处在断裂位置。该推断已经被钻探验证。另外小波四阶细节(场源似深度456 m)表现为区域场特征,推断该区深度456 m以下存在磁铁矿体的可能不大,对位于异常中心的5号地质剖面的正演计算没有发现剩余异常,也映证了该区深部没有隐伏铁矿体。小波多尺度分析与2.5维人机交互反演技术等综合方法技术的应用,加深了对该区磁异常特征的认识,可以为钻孔布置提供有力的佐证。The overburden 200 m thick in Galinge area makes it hardly possible to carry out geological work,and the limited drilling work has added difficulty to the deep ore body exploration.Based on previous work,the authors employed wavelet transform to analyze the plane magnetic anomalies and found that the details at 1st scale and 2nd scale of the wavelet highlights the characteristics of a fault in the vicinity of Line 3.Meanwhile the 2.5D inversion method applied on Line 3 showed that the fault does exist,and this has later been confirmed by drilling.Besides,the authors found that the 4th detail of wavelet analysis is a regional anomaly,whose depth might be 456 m below the surface.It is thought that there may be no magnetite body below the depth of 456 m.The authors also conducted forward calculation for Line 5 located in the anomaly center,and found no residual anomaly,suggesting the nonexistence of hidden deep ore bodies.The authors have obtained a deep understanding of the geological conditions by application of wavelet multi-scale analysis and 2.5D inversion method to the magnetic anomalies,and this approach can provide the strongest evidence for further drilling work.

关 键 词：磁法勘探 小波多尺度分解 二度半人机交互反演 尕林格铁矿区 

分 类 号：P631[天文地球—地质矿产勘探]