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Making Reliable Shear-Wave Splitting Measurements
Bulletin of the Seismological Society of America, 2013Shear-wave splitting (SWS) analysis using SKS, SKKS, and PKS (here- after collectively called XKS) phases is one of the most commonly used techniques in structural seismology. In spite of the apparent simplicity in performing SWS measure- ments, large discrepancies in published SWS parameters (fast direction and splitting time) suggest that a ...
K. H. Liu, S. S. Gao
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Thin layers and shear‐wave splitting
GEOPHYSICS, 1991The near‐surface weathering layer is considered by many to be strongly anisotropic. Any shear‐wave signal passing through this low‐velocity layer will inherit, to some degree, the anisotropic response of this layer. For thin weathering layers, information about previous anisotropic events may be distorted; when the thickness of this layer approaches ...
R. D. Slack +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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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 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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Detecting false indications of shear‐wave splitting
SEG Technical Program Expanded Abstracts 2002, 2002Summary Observations of shear-wave splitting from converted-wave seismic surveys are becoming common. When interpreting 3-C data for shear-wave splitting, it is important to be able to distinguish true indicators of shear-wave splitting from false ones.
Bruno Gratacos +2 more
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Shear-wave splitting measurements — Problems and solutions
Tectonophysics, 2008Abstract We compare sensitivity and reliability of three basic techniques of shear-wave splitting analysis – cross-correlation of wave components, minimization of covariance matrix eigenvalues and minimizing energy on the transverse component – of both synthetic and real data, point out some problems and propose solutions.
Luděk Vecsey +2 more
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Measuring Shear-wave Splitting Using Seismic Anisotropy
Proceedings, 2014In this study, we investigate the feasibility of using microseismic data to invert for fracture density, fracture strike and fracture compliance ratio from shear splitting results. We simulate microseismic waveforms by propagating a moment tensor point source disturbance in a heterogeneous isotropic media using a finite difference program.
Yousef, B. M. +4 more
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Estimating interval shear‐wave splitting from multicomponent virtual shear checkshots
SEG Technical Program Expanded Abstracts 2008, 2008Measuring shear-wave splitting from vertical seismic profiling (VSP) data can benefit fracture and stress characterization as well as seismic processing and interpretation. The classic approach to measuring azimuthal anisotropy at depth involves layer stripping.
Andrey Bakulin, Albena Mateeva
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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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