Correlating Resistivity and Gravity Survey Data from the Suswa Geothermal Prospect in Kenya

Abstract

Magnetotelluric (MT) method is prefered for sub-surface exploration of geothermal areas. The MT method is effective for delineating geothermal reservoirs that are characterized by high resistivity contrast between the reservoir and the overlaying cap rock (clay caps), The transient electromagnetics (TEM) was used to resolve the static shift problem in MT due to its good resolution near the surface. In this study, we investigate the geothermal potential over the Suswa geothermal prospect through correlation of electromagnetic and gravity survey results. The two data sets show quiet a good correlation and thus helps us confirm there exists a geothermal system at Suswa. A look at the resistivity maps reveal a low-resistivity anomaly at depth which is probably the deeper conductor acting as a heat source on the northern and the southern part of the prospect. This is confirmed by a high-density body seen on the gravity survey at similar locations of the prospect.