Spatially limited tomographic inversion for time-lapse oil reservoir monitoring

Abstract

In this paper, we discuss time-lapse reservoir fluid monitoring of the real oil-reservoir circumstances using the seismic travel time tomography. This reservoir has been carried out fluid injection for enhanced oil recovery (EOR). In order to evaluate the applicability of the seismic tomography to the fluid injection EOR monitoring, a numerical experiment was carried out. As ordinary tomography inversion failed to obtain the good result, an inversion technique was developed under the assumption that ``velocity change occurs mainly in the reservoir" during the EOR process. A velocity calibration method for the direct imaging of injected fluid front was also developed. The results of the calibration suggest the advanced usage of the seismic tomography for the fluid injection EOR monitoring.