Iterative Migration In Marine CSEM Data Interpretation

In this paper we consider an application of the ideas of electromagnetic (EM) migration to the interpretation of a typical marine controlledsource (MCSEM) survey, which consists of a set of sea-bottom receivers and a moving electrical bipole transmitter. The 3-D interpretation of the MCSEM data is a very challenging problem because of the enormous amount of computations required in the case of the multi-transmitter and multi-receiver data acquisition systems used in these surveys. At the same time, we show that the MCSEM surveys with their dense system of transmitters and receivers happen to be extremely well suited for application of the migration method. In order to speed up the computation of the migration field, we apply a fast form of integral equation (IE) solution based on the multigrid quasi-linear (MGQL) approximation. The principles of the migration imaging formulated in this paper are tested on a typical model of a sea-bottom petroleum reservoir.