Verdon, JP, Angus, DA, Kendall, JM et al. (1 more author) (2008) The effect of microstructure and nonlinear stress on anisotropic seismic velocities. Geophysics, 73 (4). D41 - D51. ISSN 0016-8033
Abstract
Recent work in hydrocarbon reservoir monitoring has focused on developing coupled geomechanical/fluid-flow simulations to allow production-related geomechanical effects, such as compaction and subsidence, to be included in reservoir models. To predict realistic time-lapse seismic signatures, generation of appropriate elastic models from geomechanical output is required. These elastic models should include not only the fluid saturation effects of intrinsic, shape-induced, and stress-induced anisotropy, but also should incorporate nonlinear stress-dependent elasticity. To model nonlinear elasticity, we use a microstructural effective-medium approach in which elasticity is considered as a function of mineral stiffness and additional compliance is caused by the presence of low-aspect ratio displacement discontinuities. By jointly inverting observed ultrasonic P- and S-wave velocities to determine the distribution of such discontinuities, we assessed the appropriateness of modeling them as simple, planar, penny-shaped features. By using this approximation, we developed a simple analytical approach to predict how seismic velocities will vary with stress. We tested our approach by analyzing the elasticity of various sandstone samples; from a United Kingdom continental shelf (UKCS) reservoir, some of which display significant anisotropy, as well as two data sets taken from the literature.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 27 Jan 2014 15:03 |
Last Modified: | 15 Sep 2014 02:26 |
Published Version: | http://dx.doi.org/10.1190/1.2931680 |
Status: | Published |
Publisher: | Society of Exploration Geophysicists |
Identification Number: | 10.1190/1.2931680 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:77390 |