1887

Abstract

Summary

Commonly, time-shifts in the post-stack domain are measured and directly linked to the vertical strain. However, this analysis is subject to the limitations of the post-stack data. On the other hand, pre-stack domain time-shifts can deliver localized, angle-dependent velocity change information. In this study, we propose a general framework for the pre-stack time-shift inversion. We start with the third order elasticity model to develop an anisotropic model for the time-lapse velocity changes. The inversion consists of an angle-band tomography to invert for the angle-dependent velocity changes, which are then used to link the velocity change to the strain changes and R-factors. The application to the real data shows the consistency of the proposed inversion with the geomechanical modelling. However, despite being consistent, it suggests implications regarding the ratio of strain components in the overburden which require revisiting the geomechanical modelling.

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/content/papers/10.3997/2214-4609.202310954
2023-06-05
2026-02-11
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References

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