Transient electromagnetic inverse time migration imaging method
CHEN Zi-Jing1(), CHEN Qing-Li2
1. No. 1 Oil Production Plant of Northwest Oil Field Company, Sinopec, Luntai 841600, China 2. School of Geophysics and Petroleum, Yangtze University, Wuhan 430100, China
In this paper, inverse time migration imaging of center loop transient electromagnetic sounding is studied. In view of the fact that the propagation velocity of electromagnetic wave in the earth is much lower than that of the speed of light in the vacuum, an inverse time migration imaging algorithm is designed which is suitable for transient electromagnetic sounding in the center loop observation configuration. The core idea of the algorithm is to obtain the total wave field value of the imaging point according to the superposition of the wave field value of different observation points at the same time of the imaging point. Based on this algorithm, inverse time migration imaging was performed on a measured center loop transient electromagnetic sounding data. It is shown that the results of inverse time migration imaging are in good agreement with the actual situation and can obtain better processing effect. Therefore, inverse time migration imaging is an effective data processing method for transient electromagnetic sounding.
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