A Feasibility Study of Land CSEM Reservoir Monitoring: The Effect of the Airwave

The displacement of oil with saline water creates a resistivity change that might be detectable by time-lapse CSEM measurements. Because the difierence in measured EM signals before and after production is small, acquisition design plays an important role. We carried out numerical experiments to understand how to optimize the acquisition to best capture the time-lapse signal. Our study shows that exciting a VED source at some distance away from the target would be an attractive choice, as a HED source induces strong airwave energy masking the anomalous signal.