Yuan, Shihao, Localised FWI

Yuan, Shihao*

Time-lapse 3D elastic waveform inversion using injected grid method for monitoring reservoir

S. Singh, N. Fuji (IPGP)

FWI allows us to take into account the full information contained in seismic data. Due to very high computational cost, FWI has so far been used for either 2D full elastic media (Sears et al. 2010) or 3D acoustic (Plessix and Perkins, 2010), and 2D time-lapse mode (Quisser and Singh, 2012). However, the Earth is three-dimensional, elastic and highly heterogeneous, therefore requiring a full 3D elastic inversion. Recently, we have developed a full waveform inversion in the time lapse using an injected grid method (Borisov and Singh, 2013). The Grid Injection Method (GIM) is well suited for time-lapse seismic studies since it allows for efficient calculation of synthetic seismograms after model alterations within a localized area where changes occur only inside a reservoir. The method is based on the principles of superposition and continuity of wavefields along a boundary and only requires calculations in the sub-volume and its neighbourhood, but its application in limited to a synthetic data and small model. The method has also has application to determine high-resolution imaging of reservoir by inverting higher frequencies (60 Hz) for the reservoir.

*Shihao is a former GPX Master student 2013-2014.