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High Resolution Time Lapse Time Strains
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 80th EAGE Conference and Exhibition 2018, Jun 2018, Volume 2018, p.1 - 5
Abstract
High resolution, low noise time strain estimates are derived through a deliberate choice of penalty function in the time shift inversion. In seismic time lapse analysis, time shifts and their derivative time strain has the potential to directly pin-point transit time changes inside the producing reservoir. But time strains are noise prone, and it has proved challenging to produce high resolution, low noise time strain estimates. The high resolution character of the method presented here is demonstrated at a single trace extracted from a base line survey and compared against two monitor survey traces. Widely used smoothness penalty functions typically succeed in estimating absolute time shifts, but fail to deliver high resolution time strains; this paper shows that this can be achieved by adapting an appropriate penalty function. The resolution of the method presented here is comparable to the resolution achieved through 4D AVO inversion, as demonstrated on a 2D line. This gives promise that a joint inversion of time shifts and amplitude changes leading to improved constraints in time lapse inversion can be established.