给定观测精度下的点(线)源模型重力与磁力横向分辨能力研究  

Lateral resolution of gravity and magnetic data of point(line) source models under given survey accuracy

作　　者：张义蜜 王万银[1] 于长春 熊盛青 ZHANG YiMi;WANG WanYin;YU ChangChun;XIONG ShengQing(Institute of Gravity and Magnetic Technology,School of Geology Engineering and Geomatics,Chang'an University,Key Laboratory of Western Mineral Resources and Geological Engineering,Ministry of Education,Chang'an University,Xi'an 710054,China;China Aero Geophysical Survey and Remote Sensing Center for Natural Resources,Key Laboratory of Airborne Geophysics and Remote Sensing Geology,Ministry of Natural Resources,Beijing 100083,China)

机构地区：[1]长安大学重磁方法技术研究所,长安大学地质工程与测绘学院,长安大学西部矿产资源与地质工程教育部重点实验室,西安710054 [2]中国自然资源航空物探遥感中心,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8期2965-2981,共17页Chinese Journal of Geophysics

基　　金：国家重点研发计划项目(2017YFC0602200)之课题“综合航空地球物理探测系统集成与方法技术示范研究”(2017YFC0602201);课题“航空地球物理综合处理解释方法研究及软件开发”(2017YFC0602202);中央高校基本科研业务费专项资金—长安大学优秀博士学位论文培育资助项目(300102261717)联合资助.

摘　　要：当相邻有两个或两个以上地质体时,重力(重力异常、重力张量)和磁力(磁力异常、磁力张量)就会产生叠加,这会对横向分辨多个地质体带来较大困难,因此需要对重力和磁力横向分辨能力进行深入的研究.本文从重、磁场正演理论出发,以球体(点源模型)和无限延伸水平圆柱体(线源模型)为例研究重力异常、重力张量、化极磁力异常以及垂直磁化磁力张量的理论横向分辨能力以及在给定观测精度条件下的实际横向分辨能力.通过研究表明,重力和磁力理论横向分辨能力随深度呈线性变化;给定观测精度下的重力和磁力实际横向分辨能力与形体质量、磁矩大小及观测精度呈正相关,且实际横向分辨能力随深度呈指数衰减变化.通过重力和磁力横向分辨能力的研究将为重、磁勘探的实际应用起到指导作用.When there are two or more neighboring geological bodies,the gravity(gravity anomaly,gravity tensor)and magnetic fields(magnetic anomaly,magnetic tensor)will be superimposed,which will make it difficult to distinguish multiple geological bodies laterally.Therefore,we need to study the lateral resolution of gravity and magnetic fields.Based on the forward theory of gravity and magnetic fields,this paper takes the sphere(point source model)and the infinitely extended horizontal cylinder(line source model)as an example to study the theoretical and actual lateral resolution of gravity anomalies,gravity tensors,reduction to the pole magnetic anomalies,and vertical magnetization magnetic tensors.The results show that the theoretical lateral resolution varies linearly with depth.The actual lateral resolution of gravity and magnetic data under given survey accuracy is positively correlated with mass,magnetic moment and survey accuracy.The actual lateral resolution decreases exponentially with depth.This study will guide the practical application of gravity and magnetic exploration.

关 键 词：横向分辨能力 重力异常 重力张量 化极磁力异常 垂直磁化磁力张量 

分 类 号：P631[天文地球—地质矿产勘探]