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2002
This chapter focuses on seismological aspects of seismic anisotropy. It presents results that link the observations of seismic anisotropy to dynamic processes acting in the Earth. Evidence for seismic anisotropy come either from local variation of seismic velocities with respect to the direction of propagation, or from anomalies linked with their ...
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This chapter focuses on seismological aspects of seismic anisotropy. It presents results that link the observations of seismic anisotropy to dynamic processes acting in the Earth. Evidence for seismic anisotropy come either from local variation of seismic velocities with respect to the direction of propagation, or from anomalies linked with their ...
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Mantle dynamics and seismic anisotropy
Earth and Planetary Science Letters, 2010Abstract Observations of seismic anisotropy yield some of the most direct constraints available on both past and present-day deformation in the Earth's mantle. Insight into the character of mantle flow can also be gained from the geodynamical modeling of mantle processes on both global and regional scales.
Maureen D. Long, Thorsten W. Becker
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Seismic Anisotropy from 6C Observations
2023A new approach is proposed for measuring the local dispersion curves of surface waves in weakly anisotropic media using a single, multi-component station, which consists of translation and rotation or strain. We directly extract the local azimuth-dependent phase velocity of the Rayleigh wave from the 6C amplitude ratio using seismic arrays deployed in ...
Le Tang +2 more
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Petrological constraints on seismic anisotropy
Physics of the Earth and Planetary Interiors, 1989The purpose of this paper is to investigate the correlations between anisotropic parameters for different orientations and mineralogies for realistic mineralogical and petrological models of the upper mantle. Such correlations make it possible to reduce the number of independent parameters required in seismic modelling of the upper mantle.
Montagner, Jean-Paul, Anderson, Don L.
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Seismic Anisotropy and Global Geodynamics
Reviews in Mineralogy and Geochemistry, 2002For many years, seismic anisotropy was often neglected, mostly because of the inherent heavy mathematical and computational tools needed to describe and model its effects on seismic waves. The usual basic knowledge about propagation in isotropic media cannot easily apply to anisotropic media, where new phenomena come up, such as birefringence (or shear-
J.-P. Montagner, L. Guillot
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Interpretation of seismic anisotropy parameters
53rd EAEG Meeting, 1991In accordance with experimental data, in many cases sedimentary deposits are found to be anisotropic media for long seismic waves. With sufficient approximation the model of these rocks is transversely isotropic media (TIM) with horizontal or vertical plane of isotropy, and they are called polar or azimuthal anisotropy, respectively.
F. M. Lyakhovitsky, L. Y. Brodov
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Seismic anisotropy and mantle flow
Journal of Geophysical Research: Solid Earth, 1989Seismic anisotropy in the mantle is primarily due to deformation‐induced lattice preferred orientation (LPO) of olivine crystals. The aim of this paper is to better understand how such LPO is produced by flow, and to learn whether observations of seismic anisotropy can be used to infer the local direction of flow within the mantle.
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