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2022 Vol.59, Issue 4 Preview Page

Technical Report

A Review of the Time-domain Electromagnetic Method: Research Trends and Applications

시간영역 전자탐사법: 연구 동향과 적용

In Seok Joung1
,
Sung Oh Cho2
,
Bitnarae Kim3
,
Juyeon Jeong4
,
Soocheol Jeong5
,
Hangilro Jang6
,
Pierre-Alexandre Reninger7
,
Myung Jin Nam89†
정 인석1
,
조 성오2
,
김 빛나래3
,
정 주연4
,
정 수철5
,
장 한길로6
,
Pierre-Alexandre Reninger7
,
남 명진89†
1Master's and PhD Integrated Course, Department of Energy and Mineral Resources Engineering, Sejong University, Seoul, Korea
2Researcher, Archaeological Studies Division, National Research Institute of Cultural Heritage, Daejeon, Korea
3Post-doctoral Fellow, BRGM, French Geological Survey, Geo-Resources Direction, Orléans, France
4Master's Degree, Department of Energy and Mineral Resources Engineering, Sejong University, Seoul, Korea
5Senior Researcher, Korea Institute of Geoscience and Mineral Resources, Seoul, Korea
6Manager, Bomin Global Co., Anyang, Korea
7Principal Researcher, BRGM, French Geological Survey, Geo-Resources Direction, Orléans, France
8Professor, Department of Energy Resources and Geosystems Engineering, Sejong University, Seoul, Korea
9Professor, Department of Energy & Mineral Resources Engineering, Sejong University, Seoul, Korea
1세종대학교 에너지자원공학과 석박통합과정
2국립문화재연구원 보존과학연구실 연구원
3BRGM, French Geological Survey, Geo-Resources Direction, Orléans, France, 박사후연구원
4세종대학교 에너지자원공학과 석사과정
5한국지질자원연구원 DMR융합연구단 선임연구원
6보민글로벌 주식회사 과장
7BRGM, French Geological Survey, Geo-Resources Direction, Orléans, France, 책임연구원
8세종대학교 지구자원시스템공학과 교수
9세종대학교 에너지자원공학과 교수
*Corresponding Author
31 August 2022. pp. 364-378
PDF XML Citation
Abstract

Time-domain/transient electromagnetic (TEM) survey measures changes in the electromagnetic (EM) field with respect to time, after an artificially generated electric or magnetic field is discontinued. Therefore, only secondary magnetic fields are measured that are free from the primary magnetic fields. Theoretically, TEM measurements are frequency responses that provide information on the conductivities of shallow to deep sub-surfaces. TEM data, normally stacked, are corrected during data processing. TEM measurement responses for synthetic models can be numerically computed using the finite difference, finite element, and finite volume methods. In this review, initially we have discussed the basic theory of the TEM method and TEM survey systems by classifying them into loop and ground-wire transmitters. Subsequently, we discussed data processing, modelling, and inversion. Finally, we discussed field survey cases from various application fields by classifying them into land, marine, and airborne TEM systems.

Keywords
Time-domain electromagnetic method
secondary field
data processing
field survey

시간영역 전자탐사법(time-domain/transient electromagnetic, TEM)은 인공적으로 발생시킨 전기장 혹은 자기장을 차단했을 때의 자기장의 시간에 따른 변화를 측정하는 탐사법이다. TEM은 송신원에 전류를 차단한 이후 측정하므로 1차 자기장의 영향 없이 지하 매질의 정보가 있는 2차장만을 측정하게 된다. 이론적으로는 TEM은 지하 전도체에 대한 모든 진동수 반응, 즉 천부에서 심부까지의 정보 획득이 가능하다. TEM자료는 겹쌓기(stacking)와 자료보정 과정을 거치게 되며, 수치 모델에 대한 TEM 반응은 유한차분법, 유한요소법, 유한체적법 등의 기법을 이용하여 수치적으로 계산 가능하다. 이 기술보고에서는 TEM의 기본 원리와 탐사 시스템을 코일 송신원과 접지 전선 송신원으로 분류해 소개하였다. 이후 기존의 자료처리와 모델링, 역산에 대해 분석하고 육상과 해양, 항공 시간영역 전자탐사로 분류하여 다양한 분야에서의 적용사례들에 대해서 소개하고자 한다.

키워드
시간영역 전자탐사
2차장
자료처리
현장탐사
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Information
  • Publisher :The Korean Society of Mineral and Energy Resources Engineers
  • Publisher(Ko) :한국자원공학회
  • Journal Title :Journal of the Korean Society of Mineral and Energy Resources Engineers
  • Journal Title(Ko) :한국자원공학회지
  • Volume : 59
  • No :4
  • Pages :364-378
  • Received Date : 2022-07-05
  • Revised Date : 2022-08-25
  • Accepted Date : 2022-08-29
  • DOI :https://doi.org/10.32390/ksmer.2022.59.4.364
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