Time-lapse full-waveform inversion as a reservoir monitoring tool - a North Sea case study

We demonstrate a 4D FWI technique using a synthetic study involving 3D elastic modeling through a highly realistic Earth model akin to the actual Grane PRM data. For this acquisition configuration, this study also indicates there is minimal sensitivity of the method to various residual uncertainties in the data and the modeling. 4D FWI results using the real time-lapse Grane PRM data with a six month acquisition interval between vintages shows changes at the reservoir level that correlate with both injecting and producing wells. In addition, we find good agreement comparing the velocity differences from 4D FWI to 4D time-shifts from the fully processed and imaged seismic data.