資源開発技術・開発機械

[2401-09-01] Fictitious Wave DomainにおけるReverse Time Migration

^○アマニ サジャッド¹、三ケ田 均¹、武川 順一¹ (1. 京都大学)

司会: 里見知昭（東北大学）

キーワード：Reverse Time Migration、マクスウェル方程式、Diffusive Domain、仮想領域

Connections between seismic and marine CSEM data are established by analytically transforming the diffusive Maxwell’s equations to wave-domain Maxwell’s equations. The two data types are similar. Also, it has been proposed previously that the solution of Maxwell’s equations in the fictitious domain has more sensitivity than the diffusive domain. So, it would be possible to monitor the deeper structure using data set in the fictitious domain even under strong attenuating media. In this study we apply the Reverse Time Migration (RTM) in the fictitious domain to investigate the deep reservoirs in conductive media. We confirm the effectiveness of our approach using numerical experiments. Synthetic data set of CSEM is prepared by the finite-difference method. We use three types of received components for RTM; i) Ex (electric field in x direction), ii) Ey (electric field in y direction), iii) Hz (magnetic field in z direction). We compare these results and investigate the effect of selected component on the migration image. Since the results of RTM with different received components show distinctive characteristics, it is important to use and interpret each result separately.