Skin depth verification of the electromagnetic waves for hydrocarbon detection

Abstract

Marine controlled-source electromagnetic method (MCSEM) for seabed logging (SBL) uses a dipole source to generate low-frequency signals, and arrays of receivers to map the potential presence of hydrocarbon reservoirs. The characteristic depth of signal penetration in the subsurface, termed as skin depth, is one of the key parameters. However, the electromagnetic response by the resistive target in contrast to the skin depth evaluation has been less thoroughly documented. In this paper, a lab scale testing is performed to generate a data set with precisely scaled dimensions. The purpose is to verify the skin depth phenomenon in complex stratified mediums for hydrocarbon detection. The synthetic electromagnetic data is produced using 1D modeling to validate the experimental results. The calculated correlation coefficient (CC) of more than 0.9 showed a good agreement between experimental and synthetic response. This outcome reveals that the depth of hydrocarbon detection does not solely depend on the skin depth of the applied frequency. The validated results recommend that a broadband electromagnetic transmitting system may reveal more authentic information about the hydrocarbon presence and extent of the hydrocarbon prospects.