基于多频电磁法水下目标体探测能力分析  

Analysis of underwater target detection capability based on multi frequency electromagnetic method

作　　者：巩铭扬 黄鑫[1] 严良俊[1] 谢兴兵[1] 周磊[1] 曹晓月 GONG MingYang;HUANG Xin;YAN LiangJun;XIE XingBing;ZHOU Lei;CAO XiaoYue(Key Laboratory of Exploration Technologies for Oil and Gas Resources,Ministry of Education,Yangtze University,Wuhan 430100,China)

机构地区：[1]油气资源与勘探技术教育部重点实验室(长江大学),武汉430100

出　　处：《地球物理学进展》2024年第4期1658-1669,共12页Progress in Geophysics

基　　金：国家自然科学青年基金项目“基于间断谱元法的裂缝介质瞬变电磁三维各向异性正演研究”(42104070);国家自然科学基金面上项目“考虑激电效应的裂隙介质瞬变电磁时移数据三维反演研究”(42374096);国家自然科学基金重点项目“水力压裂时域电磁监测方法研究与综合应用”(42030805);湖北省自然科学基金面上项目“基于三维地面和井中可控源电磁法联合反演的湖北大冶危机矿山深部矿产勘探研究”(2022CFB229);国家自然资源部电磁测深技术重点实验室开放基金“三维地面和航空大地电磁法数据联合反演研究”(KLGEPT202204)联合资助。

摘　　要：海洋资源对国家长足发展至关重要,如何完善海洋资源普查已经成为各国关注焦点.水下目标体的精准探测已成为地球物理领域研究的热点问题.电磁勘探方法以电阻率差异为基础,可以有效提取与识别水下高阻或高导目标体,是海洋地球物理探测的关键技术之一.航空电磁法由于采用机载平台可快速完成海域区数据采集,在海域资源普查、环境监测等方面得到广泛应用.然而,海洋环境复杂多变,基于一维海—地地电模型的正演模拟与反演解释技术难以对三维复杂地电结构进行刻画,严重阻碍了机载平台的多频电磁数据的精细化解释.本文采用六面体网格谱元法进行海-地电模型高精度多频航空电磁三维正演.并对水下目标开展频率域电磁探测数值模拟分析,总结不同条件下频率域电磁场传播规律,探究多频电磁系统对水下目标体的识别能力,为多频电磁系统在低空海域高导目标体有效探测提供理论参考.Ocean resources are crucial for the sustainable development of a country,and improving marine resource surveys has become a focal point for many nations.Accurate detection of underwater targets has become a hot topic in the field of geophysics.The electromagnetic exploration method,based on differences in resistivity,can effectively extract and identify underwater high-resistivity or high-conductivity targets,making it one of the key technologies in marine geophysical exploration.Airborne electromagnetic methods,using airborne platforms,enable rapid data acquisition in marine areas and have been widely applied in marine resource surveys and environmental monitoring.However,the marine environment is complex and dynamic,and the forward modeling and inversion interpretation techniques based on one-dimensional marine-land geoelectric models struggle to characterize three-dimensional complex geoelectric structures.This severely hinders the detailed interpretation of multi-frequency electromagnetic data from airborne platforms.In this study,a hexahedral mesh spectral element method is used for high-precision multi-frequency airborne electromagnetic three-dimensional forward modeling of the marine-land geoelectric model.Numerical simulations and analysis of frequency-domain electromagnetic detection of underwater targets are conducted,summarizing the propagation characteristics of frequency-domain electromagnetic fields under different conditions.The study explores the identification capability of multi-frequency electromagnetic systems for underwater targets,providing theoretical references for the effective detection of high-conductivity targets in low-altitude marine areas using multi-frequency electromagnetic systems.

关 键 词：多频电磁法 水下目标体 三维正演 谱元法 

分 类 号：P631[天文地球—地质矿产勘探] P738[天文地球—地质学]