Crosswell Electromagnetic Tomography in Saudi Arabia - From Field Surveys to Resistivity Mapping

A series of crosswell Electromagnetic surveys were made at the super giant Ghawar oil field in Saudi Arabia as part of an ongoing project to apply deep EM technology to map oil and water saturated regions within the field. The technology applies the principle electromagnetic induction and tomographic imaging to obtain the interwell resistivity distribution. The surveys which utilized existing wells and one newly drilled well were able to successfully collect data at well spacings of more than 800m. Recovered images were consistent with logs and often revealed an interwell resistivity section much different than the interpolated logs suggest.