Extending shear-wave tomography for the lower mantle using S and SKS arrival-time data
نویسندگان
چکیده
منابع مشابه
Mantle shear-wave tomography and the fate of subducted slabs.
A new seismic model of the three-dimensional variation in shear velocity throughout the Earth's mantle is presented. The model is derived entirely from shear bodywave travel times. Multibounce shear waves, core-reflected waves and SKS and SKKS waves that travel through the core are used in the analysis. A unique aspect of the dataset used in this study is the use of bodywaves that turn at shall...
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SH signals recorded by an array of four broadband (Benioff 1-90) instruments, run by Caltech, are inspected for evidence of a lower mantle shear wave velocity discontinuity previously detected using WWSSN data. Deep focus earthquakes beneath Argentina span the distance range 78 ø to 82 ø from the array, where the triplication in the travel time curve produced by the discontinuity is expected to...
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[1] A lower mantle S wave triplication (Scd) has been recognized for many years and appears to be explained by the recently discovered perovskite (PV) to postperovskite (PPV) phase change. Seismic observations of Scd display (1) rapid changes in strength and timing relative to S and ScS and (2) early arrivals beneath fast lower mantle regions. While the latter feature can be explained by a Clap...
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We applied the stochastic method of Gudmundsson, Davies & Clayton (1990) (which was applied to ISC P-wave data) to teleseismic ISC S-wave data to obtain an independent estimate of mantle structure. We inverted the variance of S-wave traveltime residuals of bundles of rays to obtain a description of the spectrum of lateral heterogeneity as a function of depth through the mantle. The technique yi...
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ژورنال
عنوان ژورنال: Earth, Planets and Space
سال: 1998
ISSN: 1880-5981
DOI: 10.1186/bf03352194