Effect of Offline Electrode Error on 2D Resistivity Survey along a Curved Survey Line

In Ky Cho

doi:10.32390/ksmer.2022.59.6.644

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2022 Vol.59, Issue 6 Preview Page Next Page

Research Paper

Effect of Offline Electrode Error on 2D Resistivity Survey along a Curved Survey Line 휘어진 측선상 2차원 전기비저항 탐사에서 오프라인 전극의 영향

31 December 2022. pp. 644-655

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Abstract

In a two-dimensional (2D) resistivity survey, all electrodes are assumed to be equally spaced and located on a straight survey line. However, due to the surface constraints of the survey areas, this underlying assumption is usually not followed in fieldwork. Moreover, misplaced electrodes inevitably result in significant distortions of subsurface images. In a 2D resistivity survey, the following two types of electrode location errors have been observed: inline spacing error and offline electrode error. Although inline spacing error leads to more distortion in data than offline electrode error, the latter can also generate false anomalies, leading to misinterpretation of data. In this study, I analyzed the effect of offline electrode error through numerical modeling using true electrode coordinates. Furthermore, I propose a new inversion algorithm developed using true electrode coordinates; I examine its performance through numerical experiments and field data applications.

Keywords

2D resistivity survey

electrode location error

inline spacing error

offline electrode error

일반적으로 2차원 전기비저항 탐사에서는 이론적으로 모든 전극이 직선 측선상에 동일한 간격으로 배치되어 있다고 가정한다. 그러나 조사 지역의 여건상 실제 현장 작업에서는 이러한 가정을 만족하지 못하는 경우가 빈번하며, 잘못된 전극위치는 지하 영상의 왜곡을 초래한다. 2차원 전기비저항 탐사에서 전극위치 오류에는 인라인 전극 오차와 오프라인 전극 오차가 있다. 일반적으로 인라인 전극 오차가 오프라인 전극 오차보다 더 크지만, 오프라인 전극 오차도 잘못된 이상체를 생성하여 잘못된 해석으로 이어질 수 있다. 이 연구에서는 실제 전극위치를 고려한 수치 모델링을 통해 오프라인 전극 오차의 영향을 분석하였다. 또한, 근본적인 문제 해결을 위하여 실제 전극위치를 사용하는 새로운 역산 알고리즘을 제안하고, 수치실험 및 현장 적용을 통해 제안된 알고리즘의 타당성을 검증하였다.

키워드

2차원 전기비저항 탐사

전극위치 오차

인라인 전극 오차

오프라인 전극 오차

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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 :6
Pages :644-655
Received Date : 2022-10-28
Revised Date : 2022-12-09
Accepted Date : 2022-12-27
DOI :https://doi.org/10.32390/ksmer.2022.59.6.644

Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

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