Petratherm contracted Quantec Geoscience Pty Ltd to record the Ferguson Hill Magneto-Telluric Survey during November 2007. The purpose of the survey was to determine the depth to basement and the potential for the area to host a geothermal energy resource. A total of 29 stations were recorded, spaced 500m apart in a single NE-SW transect across GEL 158. GEL 158 is located on Stuart Creek Pastoral Lease some 90 km north of Roxby Downs. The survey was deemed an operational and technical success with excellent data recorded. Interpretation of existing data (gravity and magnetics) had identified a Radiogenic Iron Oxide (RIO) source of geothermal heat at an estimated depth of approximately 2500m. It was hoped that the area may have a blanket cover of at least 3000m of insulating material for it to be a viable geothermal prospective area. Interpretation of the new data by the Bostick and Occam 1D models and the RLM and PW 2D Model approach produced similar results, namely, a basic 3 layer resistivity case with a depth to basement in the area of 1800-2000m depth. This was not considered thick enough and as such the area deemed to not have much geothermal potential.