Integration of seismic first arrival times to estimate water-air contact and initial water saturation
© 2017 Elsevier B.V. History matched models have helped reservoir engineers obtain a better understanding of the reservoir and optimize the future productions. Recent years, seismic data is more often to be integrated to improve the reservoir models, however, seismic data has to be inverted to seismic impedance values first. In this study, we introduce a new way to improve the initial reservoir models -integrating the seismic first arrival times to estimate the fluid contacts and initial water saturation. The key aspect of this method that distinguishes it from other methods is that seismic data is integrated directly. As a result, traditional seismic inversion step is not needed, and the data integration are through the comparison of observed first arrival times and simulated first arrival times (raytracing results). In our paper, the feasibility of using seismic first arrival times to improve initial reservoir models is discussed, and the method is verified by using sand tank experiment data. The observed seismic first arrival times were collected during the experiment, and the simulated first arrival times were calculated by seismic raytracing program. Trust region method was used to adjust water-air contact depth and initial water saturation to minimize the difference between simulated and observed data. At last, a good estimation of initial condition is achieved, and it demonstrates a potential of integrating seismic data to improve the reservoir models without an inversion step.
Publication Source (Journal or Book title)
Journal of Natural Gas Science and Engineering
Sun, T., Shuai, Y., White, C., Lorenzo, J., & Chollett, S. (2017). Integration of seismic first arrival times to estimate water-air contact and initial water saturation. Journal of Natural Gas Science and Engineering, 45, 391-398. https://doi.org/10.1016/j.jngse.2017.05.011