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http://dx.doi.org/10.7582/GGE.2011.14.3.185

A Scheme for Computing Primary Fields in Modeling of Marine Controlled-Source Electromagnetic Surveys  

Kim, Hee-Joon (Department of Energy Resources Engineering, Pukyong National University)
Publication Information
Geophysics and Geophysical Exploration / v.14, no.3, 2011 , pp. 185-190 More about this Journal
Abstract
In marine controlled-source electromagnetic (CSEM) modeling, it may be difficult to evaluate primary fields accurately using conventional linear filters because they decay very rapidly with distance. However, since there exists a closed-form solution to the Hankel transform in TM mode for a homogeneous half space, we can assess the accuracy of linear filters for evaluating the Hankel transform. As a result, only nine out of 36 source-receiver pairs show that EM fields decrease linearly in semi-log scale with an increase of source-receiver distance, while EM fields are either 0 or not reduced significantly due to an effect of the air layer. There also exist closed-form solutions for the nine pairs, and the others can be evaluated accurately with a relatively short filter. This paper proposes a method which uses closed-form solutions for TM-mode Hankel transforms and a filter with 61 coefficients for TE-mode ones.
Keywords
marine CSEM; linear filter; half space; TM mode; Hankel transform;
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Times Cited By KSCI : 1  (Citation Analysis)
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