基于航磁矢量数据的磁源总磁化方向估算  

Estimating total magnetization direction of magnetic sources by using airborne vector magnetic data

作　　者：谢汝宽 熊盛青 段树岭 王金龙 骆遥 王平 段然 刘浩军 范正国 XIE RuKuan;XIONG ShengQing;DUAN ShuLing;WANG JinLong;LUO Yao;WANG Ping;DUAN Ran;LIU HaoJun;FAN ZhengGuo(School of Geophysics and Information Technology,China University of Geosciences(Beijing),Beijing 100083,China;China Aero Geophysical Survey and Remote Sensing Center for Natural Resources,Beijing 100083,China;Key Laboratory of Airborne Geophysics and Remote Sensing Geology,Ministry of Natural Resources,Beijing 100083,China)

机构地区：[1]中国地质大学(北京)地球物理与信息技术学院,北京100083 [2]中国自然资源航空物探遥感中心,北京100083 [3]自然资源部航空地球物理与遥感地质重点实验室,北京100083

出　　处：《地球物理学报》2021年第9期3368-3378,共11页Chinese Journal of Geophysics

基　　金：国家重点研发计划(2017YFC0602000,2017YFC0602200);国家高技术研究发展计划(863计划)(2013AA063901);中国地质调查项目(DD20160066,DD20211396)联合资助.

摘　　要：在地质体具有较强剩磁或自退磁效应的情况下,获得地质体总磁化方向对磁法勘探的数据处理、反演及解释具有重要意义.与传统航磁总场测量相比,航磁矢量(三分量)测量能够获得地磁场的矢量信息.基于三分量磁异常一阶矩与磁源磁矩的积分关系,我们实现了基于航磁矢量数据的磁源总磁化方向估算.针对该方法易受相邻异常影响,从而使多异常的估算难以确定磁源中心位置的问题,分析了在不同磁化倾角下,估算的磁化偏角、倾角与实际磁源中心位置的关系,并根据该关系采取了限定估算区域的方法,获得了多异常的估算结果.将该方法应用于东天山启鑫地区实测航磁三分量数据,估算了具有强剩磁的启鑫岩体总磁化方向,并将估算的方向应用于化极计算.化极结果显示,减少了启鑫岩体磁异常受斜磁化的影响,且与磁异常模量计算结果类似.该方法假设磁源均匀磁化,估算结果可视为地质体总磁化方向的整体体现,对强剩磁地质体磁异常的数据处理、反演及解释具有实际意义.Estimating total magnetization direction plays an important role in data processing,inversion and interpretation for magnetic sources with strong remanence and self demagnetization effect.Compared with traditional aeromagnetic total-field survey,airborne vector magnetic survey can measure vector magnetic information.Based on the integral relationship between the first order moment of the three-component magnetic anomalies and the magnetic moment of magnetic sources,we presented the total magnetization direction estimation method of magnetic sources by using airborne vector magnetic data.The method is easy to be affected by adjacent anomalies,which makes it difficult to obtain the center of magnetic sources.We analyzed the location relationship between the estimated magnetization direction and the center of magnetic sources with different inclinations,and then limited the estimation area to estimate the direction for multiple anomalies.The method was applied to the airborne vector magnetic data measured at the Qixin area of the East Tianshan Mountains in China and the total magnetization direction of the Qixin Rock with strong remanent magnetization was estimated.The estimated direction was applied to the process of reduction to the pole(RTP).The RTP result shows that the asymmetry of magnetic anomalies caused by the oblique magnetization is well-eliminated and the result is similar to magnetic amplitude data.The estimated direction can be regarded as the uniform total magnetization direction,assuming the direction does not vary greatly within the magnetic sources.The method is significant to data processing,inversion and interpretation of magnetic anomalies caused by strong remanence.

关 键 词：航磁矢量测量 三分量 总磁化方向 

分 类 号：P631[天文地球—地质矿产勘探]