Three-dimensional Marine Magnetotellurics For Petroleum Exploration

In this paper we investigate the application of marine magnetotellurics for petroleum exploration. The resistivity of petroleum reservoirs and of salt structures is usually on an order greater than those of surrounding sea-bottom sediments. That is why these structures can be considered easily detectable targets for marine MT methods. We consider the schematic model of an offshore Angola sea-bottom petroleum reservoir. We examine two models. One model contains a reservoir only, another represents a more realistic model of a petroleum reservoir in the presence of a salt dome structure. We invert the synthetic data computed for the reservoir model and the model with the salt dome using the CEMI 3-D MT inversion code QAINV3D. The inversion results show that even in the case of complex sea-bottom geological structures, where the reservoir response is strongly distorted by the salt dome effect, the inversion generates a clear image of the reservoir.