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A New Understanding of Shear-Wave Splitting
Proceedings, 1995Shear-wave splitting (shear-wave- bi-refringence) diagnostic of some form of azimuthal anisotropy is widely observed in all types of rock in the uppermost 15km of the Earth's crust (Crampin and Lovell 1991).
S. Crampin, S. V. Zatsepin
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Shear Wave Splitting in Himalaya
Chinese Journal of Geophysics, 2007AbstractWe analyze the records of 56 stations in Himalaya area with the method of minimizing the eigenvalue. Splitting was observed at thirty‐nine stations of them. The average splitting time is about 0.8s. The parameters of splitting vary not only from south to north, but are also different on the two sides of the line joining the station GAIG and ...
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Bootstrapping shear-wave splitting errors
Bulletin of the Seismological Society of America, 1994Abstract We have developed a bootstrap method to estimate errors associated with inverting SKS waveforms for shear-wave splitting parameters. Although presented for shear-wave splitting inversions, this method is suitable for any waveform inversion procedure.
Eric Sandvol, Thomas Hearn
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Shear-wave splitting in compliant rocks
The Leading Edge, 2010Shear-wave splitting is a phenomenon that has received a lot of attention primarily because of its connection with vertically aligned cracks or fractures within reservoirs. However, in most cases the largest amount of shear-wave splitting is observed to occur in the near-surface layers where the rocks are the least consolidated, and so are least likely
Peter Cary +3 more
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Shear-wave splitting near Guam
Physics of the Earth and Planetary Interiors, 1992Abstract Polarities of shear waves from intermediate-focus events underneath Guam are studied. For records from a group of ten events, shear-wave splitting with faster-arriving E-W components are observed. This event group occurred within, or above, one geographic portion of the Wadati-Benioff zone, with depths ranging between 57 and 148 km.
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Amplitude effects associated with shear‐wave splitting
SEG Technical Program Expanded Abstracts 2009, 2009Shear-wave anisotropy results in a time delay between two different shear-wave polarizations S1 and S2. If there are associated differences in attenuation of the amplitudes, then simple time shifting is insufficient to match the S1 and S2 images. This ―differential‖ attenuation leads to both an additional time delay and a frequency dependent amplitude ...
Bruno Gratacos +2 more
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Evaluation of anisotropy by shear-wave splitting
Geophysics, 1985Abstract The polarizations of three-component shear wave-trains carry unique information about the internal structure of the rock through which they pass: specifically, commonly observed shear-wave splitting may contain information about the orientation of crack distributions.
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Error in shear‐wave polarization and time splitting
Geophysical Prospecting, 2004ABSTRACTShear‐wave polarization and time delay are attributes commonly used for fracture detection and characterization. In time‐lapse analysis these parameters can be used as indicators of changes in the fracture orientation and density. Indeed, changes in fracture characteristics provide key information for increased reservoir characterization and ...
Gwénola Michaud, Roel Snieder
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Splitting parameter yield (SPY): A program for semiautomatic analysis of shear-wave splitting
Computers & Geosciences, 2012SPY is a Matlab algorithm that analyzes seismic waveforms in a semiautomatic way, providing estimates of the two observables of the anisotropy: the shear-wave splitting parameters. We chose to exploit those computational processes that require less intervention by the user, gaining objectivity and reliability as a result.
Lucia Zaccarelli +2 more
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Multichannel analysis of shear wave splitting
Journal of Geophysical Research: Solid Earth, 2000A multichannel analysis is introduced to constrain seismic anisotropy from the shear wave splitting of SKS and SKKS. This technique utilizes simultaneously a set of records coming from different azimuths. The splitting intensity of SKS waves, measured by the amplitude of the transverse component, depends on the angle between the back azimuth of the ...
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