Oil field reservoir characterization and monitoring using electromagnetic geophysical techniques

This paper presents recent advances and case histories of two non-traditional electromagnetic (EM) geophysical techniques for oil reservoir characterization and production/process monitoring. The crosswell electromagnetic induction method has seen rapid advancement since its inception in the early 1990s and, to this date, numerous surveys have been completed in active oil fields as well as other sites. Here, one example is given where a two-dimensional (2D) electrical conductivity image derived from crosswell data is employed for reservoir characterization, and two other examples presented where the method provided valuable insight into the two- and three-dimensional progress of water flood operations. The second, less mature method involves the development of a new generation single hole induction logging tool. With the Geothermal Borehole Induction Logging Tool (Geo-BILT), all three components of the magnetic field at multiple offsets from a three-component source are measured. The resulting data are inverted to produce 3D estimates of the electrical conductivity distribution surrounding the borehole. For this technology, we first demonstrate the concept using synthetic data and then show some preliminary field results.