| Popis: |
Summary Full waveform inversion (FWI) is a class of inversion strategies that aim to invert the full characteristics of the seismic wavefield, amplitude, and phase of all arrivals, using the most realistic (or most appropriate) physics to describe the behaviour of the earth. One particular challenge is the incorporation of non-seismic data, such as well-log information, to provide an accurate measurement of the velocity at particular points in the subsurface. Well-log sonic velocity measurements do not match directly with seismic velocity information, because the instrumentation is different and measurements are made for waves at a different frequency regime. We propose to match a well-log derived seismic image to the migrated the seismic data as an image space constraint in FWI. We show that the sensitivity of image domain well-log constraints extends throughout the over/side-burden of wells. This provides a significant advantage over conventional model space constraints that only have sensitivity in the immediate vicinity of the wells. We demonstrate and justify our method using synthetic experiments in a complicated, realistic subsurface setting, using a model from the SEAM time-lapse pilot. |
