Journal ArticleDOI
Long-Wave Elastic Anisotropy Produced by Horizontal Layering
Reads0
Chats0
TLDR
In this article, a horizontally layered inhomogeneous medium is considered, whose properties are constant or nearly so when averaged over some vertical height l′, and conditions on the five elastic coefficients of a homogeneous transversely isotropic medium are derived which are necessary and sufficient for the medium to be "long-wave equivalent" to a horizontally-layered inhomogenous medium.Abstract:
A horizontally layered inhomogeneous medium, isotropic or transversely isotropic, is considered, whose properties are constant or nearly so when averaged over some vertical height l′. For waves longer than l′ the medium is shown to behave like a homogeneous, or nearly homogeneous, transversely isotropic medium whose density is the average density and whose elastic coefficients are algebraic combinations of averages of algebraic combinations of the elastic coefficients of the original medium. The nearly homogeneous medium is said to be ‘long-wave equivalent’ to the original medium. Conditions on the five elastic coefficients of a homogeneous transversely isotropic medium are derived which are necessary and sufficient for the medium to be ‘long-wave equivalent’ to a horizontally layered isotropic medium. Further conditions are also derived which are necessary and sufficient for the homogeneous medium to be ‘long-wave equivalent’ to a horizontally layered isotropic medium consisting of only two different homogeneous isotropic materials. Except in singular cases, if the latter two-layered medium exists at all, its proportions and elastic coefficients are uniquely determined by the elastic coefficients of the homogeneous transversely isotropic medium. The observed variations in crustal P-wave velocity with depth, obtained from well logs, are shown to be large enough to explain some of the observed crustal anisotropies as due to layering of isotropic material.read more
Citations
More filters
Journal ArticleDOI
Quantitative analysis of rock stress heterogeneity: Implications for the seismogenesis of fluid-injection-induced seismicity
C. Langenbruch,Serge A. Shapiro +1 more
TL;DR: In this paper, the authors compared elastic-rock heterogeneity measured by borehole logging to the occurrence of seismic events caused by hydraulic fracturing of the corresponding rock sections and found that significant fluctuations of rock stress originated from elastic rock heterogeneity.
Journal ArticleDOI
Seismic migration in elliptically anisotropic media1
TL;DR: In this article, a paraxial wave equation is developed for elliptical anisotropic wave propagation, which can be used for modelling or migration, and the equation is then transformed by a change of variable to a second Paraxial equation which only depends on one effective velocity field.
Journal ArticleDOI
Seismic anisotropy in gas‐hydrate‐ and gas‐bearing sediments on the Blake Ridge, from a walkaway vertical seismic profile
Ingo Pecher,Ingo Pecher,W. Steven Holbrook,Mrinal K. Sen,Daniel Lizarralde,Warren T. Wood,Deborah R. Hutchinson,William P. Dillon,H. Hoskins,Ralph A. Stephen +9 more
TL;DR: In this paper, an analysis of anisotropy in marine sediments using walkaway vertical seismic profiles from the Blake Ridge, offshore South Carolina is presented. But the authors focus on a gas-hydrate-bearing unit of clay and claystone with Thomsen parameters e = 0.19 ± 0.12.
Journal ArticleDOI
Modified effective medium model for gas hydrate bearing, clay-dominated sediments in the Krishna–Godavari Basin
TL;DR: In this article, a friction-dependent effective medium model (EMM) was proposed to understand the interaction between the sediment grains of unconsolidated marine sediments as well as with hydrate.
Book ChapterDOI
Quantitative Seismic Interpretation: Common techniques for quantitative seismic interpretation
TL;DR: In the last few decades, seismic interpreters have put increasing emphasis on more quantitative techniques for seismic interpretation, as these can validate hydrocarbon anomalies and give additional information during prospect evaluation and reservoir characterization.
References
More filters
Book ChapterDOI
The Dispersion of Surface Waves on Multilayered Media
TL;DR: In this paper, a matrix formalism developed by W. T. Thomson is used to obtain the phase velocity dispersion equations for elastic surface waves of Rayleigh and Love type on multilayered solid media.
Journal ArticleDOI
Transmission of Elastic Waves through a Stratified Solid Medium
TL;DR: In this article, the transmission of a plane elastic wave at oblique incidence through a stratified solid medium consisting of any number of parallel plates of different material and thickness is studied theoretically.
Journal ArticleDOI
Sur les équations différentielles linéaires à coefficients périodiques
TL;DR: In this paper, Gauthier-Villars implique l'accord avec les conditions générales d'utilisation (http://www.numdam.org/conditions).
Journal ArticleDOI
Wave propagation in a stratified medium
TL;DR: In this paper, the authors derived the wave equation from the stress-strain relations and the equation of motion, and showed that there are in general three characteristic velocities, all functions of the direction of the propagation.
Journal ArticleDOI
Elastic wave propagation in layered anisotropic media
TL;DR: In this article, the dispersion properties of transversely isotropic media were analyzed for a single solid layer in vacuo and a single layer in contact with a fluid halfspace, and the single layer solutions were generalized to n-layer media by the use of Haskell matrices.