Estimation of depth and location of anomalies resulting from ground electromagnetic data in the frequency domain by the depth from extreme points (DEXP) imaging method

Authors

Abstract

Imaging methods have traditionally not used with EM fields because of a belief that EM fields obey the Maxwell’s wave equations rather than Laplace’s equation. However under some approximations, image methods could be applied on frequency domain EM data. We evaluated DEXP method to estimate location of subsurface targets. We tested the performance of the DEXP method on a synthetic dataset that was generated by the COMSOL multiphysics package for a horizontal cylinder, a vertical dike and a contact. The results show remarkable and accurate estimations of depths and horizontal locations of aforementioned models. This method was also tested on a real dataset and the results were compared with the one obtained from prior information.

Keywords


احمدی، م.، ۱۳۹۴، برداشت، پردازش و تفسیر داده‌های EM34-3 و VLF در اندیس مس دوچیله- میامی و مقایسه نتایج با داده‌های مقاومت ویژه و IP، پایان­نامه کارشناسی ارشد، دانشگاه صنعتی شاهرود، دانشکده مهندسی معدن، نفت و ژئوفیزیک.
بنی­عامریان، ج.، اسکویی، ب. و جوع عطا بیرمی، ا.، ۱۳۹۵، برآورد عمق و شاخص ساختاری چشمه­های مغناطیسی با استفاده از روش‌های تحلیل چندمقیاسی و DEXP، مجله فیزیک زمین و فضا، ۴۲ (۱)، ۱۱۱-۱۲۱.
بنی­عامریان، ج.، اسکویی، ب. و فدی، م.، ۱۳۹۵، مقایسه روش‌های گوناگون برآورد عمق، مکان و نوع چشمه­ی میدان­های مغناطیسی و گرانی، مجله فیزیک زمین و فضا، ۴۲ (۲)، ۳۶۹-۳۹۱.
بهرامی، ع.، ۱۳۹۳، برداشت، پردازش و تفسیر داده‌های EM34 و مقاومت ویژه بر روی قنات در منطقه مجن و مقایسه نتایج حاصله، پایان­نامه کارشناسی ارشد، دانشگاه صنعتی شاهرود، دانشکده مهندسی معدن، نفت و ژئوفیزیک.
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