A methodology for 7D warping and deformation monitoring using time-lapse seismic data
- 1 July 2006
- journal article
- Published by Society of Exploration Geophysicists in Geophysics
- Vol. 71 (4), O21-O31
- https://doi.org/10.1190/1.2212227
Abstract
A methodology is presented for vector analysis of the image displacements (warping) between successive 3D seismic image volumes that provides 7D analysis (including lateral and vertical displacements) of in situ subsurface deformation around hydrocarbon reservoirs. The key challenges are (1) assessment of just vertical shifts is insufficient, and vector displacements should be determined; (2) robust vertical displacements can usually be derived, but lateral shifts are less well defined because of the generally smooth data character in a horizontal/horizon plane; (3) subvoxel resolution is necessary for correct matching and deformation analysis; (4) velocity and strain effects are intrinsically combined in time-lapse seismic images; (5) separation of accumulated and local effects is necessary; (6) apparently coherent and smooth displacement fields do not necessarily provide good strain analysis; (7) warping is easily degraded by noise, and good cross-matching is a prerequisite. To address these challenges, a full 3D, local warp vector derivation methodology is proposed, which involves (1) constraint using prior estimates, (2) local refinement with subvoxel resolution, and (3) 3D and vectorial conditioning using a deformable mesh with sensitivity to image-match quality. The warping approach is extended to separate accumulated from local effects and to analyze in situ deformation based on the displacement vector volume. This is achieved by a finite-element approach to determine an elemental pseudostrain tensor field and an iterative procedure to separate the pseudostrain into velocity and strain components. The approach up to the strain analysis, is demonstrated using a real data example, which indicates the potential of the methodology (accumulated overburden effects are separated to reveal a local compaction signature in the reservoir), but realistic, quantitative values of strain have not yet been realized.Keywords
This publication has 28 references indexed in Scilit:
- Cross‐matching with interpreted warping of 3D streamer and 3D ocean‐bottom‐cable data at Valhall for time‐lapse assessmentGeophysical Prospecting, 2005
- The 4D seismic response of a compacting reservoir—examples from the Valhall Field, NorwayPublished by Society of Exploration Geophysicists ,2005
- Interpreted Warping for 4D Monitoring of Production-Induced Subsidence at ValhallPublished by EAGE Publications bv ,2003
- Time‐lapse seismic analysis of pressure depletion in the Southern Gas BasinPublished by Society of Exploration Geophysicists ,2003
- 4-D constrained depth conversion for reservoir compaction estimation: Application to Ekofisk FieldGeophysics, 2002
- Time‐lapse seismic monitoring of compaction and subsidence at Valhall through cross‐matching and interpreted warping of 3D streamer and OBC dataPublished by Society of Exploration Geophysicists ,2002
- Robust cross‐equalization of 4D‐4C PZ migrated data at Teal SouthPublished by Society of Exploration Geophysicists ,2001
- 3D Image Matching Using a Finite Element Based Elastic Deformation ModelLecture Notes in Computer Science, 1999
- Rapid subsidence over oil fields measured by SAR interferometryGeophysical Research Letters, 1998
- A discrete numerical model for granular assembliesGéotechnique, 1979