基于总梯度模分析的磁源体边界信息提取及找矿意义  

Determination of the Magnetic Source Boundary Based on Total Gradient Module Analysis and Its Prospecting Significance

作　　者：吴文贤[1] 范文玉[1] 王永华[1] 吴振波[1] 杨剑[1] 焦彦杰[1] 高建华[1] 邹光富[1] 邓珂[1] 

机构地区：[1]成都地质矿产研究所,四川成都610081

出　　处：《地质与勘探》2013年第6期1164-1169,共6页Geology and Exploration

基　　金：国外矿产资源风险勘查专项资金项目(中地调发[2009]274号);中国地质调查局地质调查项目(1212011120918和12120113049600)资助的成果

摘　　要：低纬度地区磁异常的化极处理极不稳定,甚至出现奇异现象。因此,低纬度地区磁异常的化极处理一直是位场研究的难点。磁异常总梯度模的曲线形态与磁化强度的大小及方向无关,且其极大值位置与磁源边界具有一定的对应性,模型试验表明了该方法在低纬度地区磁异常分析与解释方面的有效性。本文将基于总梯度模的磁异常分析方法应用于老挝爬立山铁矿区的磁测资料处理,由此排除了由化极不稳定导致的虚假磁异常,圈定了矿致异常的分布范围,进一步指导矿区铁矿勘探。已完成的钻孔资料证明,由该方法确定的磁异常区域与区内磁铁矿体分布位置的吻合性较好。由此表明,该方法对低纬度区磁异常分析与解释具有重要的意义。The reduction-to-pole process of magnetic data at low latitude areas is usually unstable and even shows singularity. It is thus one of the most difficult problems in potential field studies. The total gradient module shape of magnetic anomalies is irrelevant to magnetization values and direc- lions, and there is a certain correspondence between magnetic boundary and total gradient magnitude maxima range. Model tests show the validity of this method fur magnetic anomaly analysis and interpretation in low-latitude areas. In this study, we use the total gradient module analysis to process the mag- netic dala from the Palisban iron ore area, Laos, and the false anomalies come from reduction-to-pnle arc excluded and the mineralized-anomaly positions arc det~＇rmined to guide the iron ore exploration. The drill holes confirm that the magnetic anmnaly positions determined by this method are identical with tbat of the magnetite ores. This shows that the method presented in this paper has significance for analysis and interpretation of magnetic anomalies in low- latitud, areas.

关 键 词：低纬度地区 磁异常 总梯度模 磁源边界 老挝爬立山铁矿区 

分 类 号：P31[天文地球—固体地球物理学]