Application of Various Geophysical Techniques to Reservoir Monitoring and Modeling

We have been developing so-called “geophysical postprocessors” since the early 1990’s. These computational tools calculate temporal changes in geophysical observables that result from changing underground conditions computed by reservoir simulations. The purpose of the development is to enable us to use monitoring data from repeat and/or continuous geophysical measurements in history-matching studies. We first developed a microgravity postprocessor, and then developed postprocessors for self-potential, electrical resistivity (DC or MT), magnetic, seismic (reflection, VSP or cross-hole) and surface-deformation measurements so far under various geothermal and CCS projects in Japan. Among recent topics, we present the results of history-matching studies using self-potential and gravity data, and introduce recent improvements made in the self-potential, seismic and surface-deformation postprocessors.