f Resolving electrical anisotropy using long-offset transient electromagnetics

The integration of different geophysical techniques is essenbal to determine accurately the petrophysical parameters of a hydrocarbon reservoir. 3D Seismics yield very good velocity information, but porosity, which is a very important parameter for hydrocarbon exploration, cannot be determined with seismics alone. Electromagnetics are increasingly used, since they measure electrical conductivity, which strongly depends on porosity. Through a proper combination of electromagnetic and seismic methods, one can obtain a very high resolution of porosity even at depths of several kilometres (Strack et al., 1991).