基于分段二分搜索算法的半航空瞬变电磁电导率深度快速成像方法研究  

Research on the Semi-airborne transient electromagnetic conductivity depth rapid imaging method based on segmented binary search algorithm

作　　者：王仕兴 易国财[1,2] 王绪本 张赛民[1,2] 郭明[1,2] 张振雄 何可 谢小国[3] WANG ShiXing;YI GuoCai;WANG XuBen;ZHANG SaiMin;GUO Ming;ZHANG ZhenXiong;HE Ke;XIE XiaoGuo(School of Geophysics,Chengdu University of Technology,Chengdu 610059,China;Key Lab of Earth Exploration and Information Techniques of Ministry of Education,Chengdu 610059,China;Sichuan Hua Di Building Engineering Company Limited,Chengdu 610081,China)

机构地区：[1]成都理工大学地球物理学院,成都610059 [2]地球勘探与信息技术教育部重点实验室,成都610059 [3]四川省华地建设工程有限责任公司,成都610081

出　　处：《地球物理学进展》2021年第3期1317-1324,共8页Progress in Geophysics

基　　金：“滑坡地质调查半航空瞬变电磁勘察实验研究”(SKLGP2020K023);国家自然科学基金项目“稳定条件突破CFL限制的显式有限差分法模拟地形模型的三维半航空瞬变电磁响应”(41974158)联合资助。

摘　　要：中心回线式直升机航空瞬变电磁法中因其发射源与接收线圈相对位置不变,故在电导率深度成像(Conductivity Depth Imaging, CDI)中无需考虑偏移距带来的影响,但半航空瞬变电磁法的工作方式是利用长导线源在地面发射,无人机搭载接收线圈在空中采集电磁响应数据,发射源与接收线圈相对位置一直变化,存在偏移距的问题,无法像航空瞬变电磁一样实现CDI快速成像.本文提出建立"库"的思想,根据不同实际情况建立不同的电导率-电磁响应数据网,利用分段二分搜索算法来消除"二值性"带来的问题,使得半航空瞬变电磁电导率深度快速成像(Semi-Airborne Transient Electromagnetic-Conductivity Depth Imaging, SATEM-CDI)方法得以实现.通过正演模拟及实测数据成像分析,表明SATEM-CDI理论简单、处理过程中无需迭代,计算速度快,可对大量半航空瞬变电磁数据进行实时成像,且成像结果可靠,可为反演模型和初步地质结构判断提供重要资料.Central loop type helicopter aviation in the transient electromagnetic method because of its source and receiver coil position unchanged, thus in the depth of the Conductivity imaging Conductivity Depth Imaging(CDI)do not need to consider in the offset the impact of air, but the workings of Semi-airborne transient electromagnetic method is to use the long wire source on the surface of the launch, The Unmanned Aerial Vehicle carries a receiver coil to collect electromagnetic response data in the air, source and receiving coils have been changing the relative position, offset problem, cannot like air transient electromagnetic rapid CDI imaging method. The idea of establishing a "database" was proposed in this paper, and different Conductivity electromagnetic response data networks were established according to different actual conditions. Meanwhile, the segmented binary search algorithm was used to eliminate the problems brought about by "binarization", so that the Semi-airborne transient electromagnetic conductivity depth imaging method could be realized. Through forward simulation and imaging analysis of measured data, it is shown that Semi-Airborne Transient Electromagnetic-Conductivity Depth Imaging(SATEM-CDI)is simple in theory, no iteration is needed in processing, and the calculation speed is fast, and a large number of Semi-airborne transient electromagnetic data can be real-time imaging, and the imaging results are reliable, which can provide important data for inversion model and preliminary geological structure judgment.

关 键 词：半航空瞬变电磁法 电导率-电磁响应数据网 分段二分搜索算法 二值性 电导率深度快速成像 

分 类 号：P631[天文地球—地质矿产勘探]