Coexisting shear- and compressional-wave seismic velocity discontinuities beneath the central Pacific
نویسندگان
چکیده
منابع مشابه
Three-dimensional Compressional- and Shear-wave Seismic Velocity Models for the Southeast Geysers Geothermal Field, California
Three-dimensional compressionaland shear-wave velocity (“Vp” and “Vs,” respectively) structure is obtained for the SE Geysers geothermal area from microearthquake arrival-time data. The results indicate a region of high Vp and high Vs in the northwest portion of the area studied, and a low value of VpNs at depths corresponding to the upper part of the steam reservoir. The Vp and Vs anomalies ar...
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In situ shear wave velocity is one of the most important parameters for evaluating dynamic elastic moduli and needs special energy sources for generation and receivers for detection. Identification of shear wave phase on a seismic record needs skill as it is not the first wave to arrive and is usually embedded in surface waves. To estimate shear wave velocity for site characterization and for p...
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Defining the mantle structure that lies beneath hot spots is important for revealing their depth of origin. Three-dimensional images of shear-wave velocity beneath the Hawaiian Islands, obtained from a network of sea-floor and land seismometers, show an upper-mantle low-velocity anomaly that is elongated in the direction of the island chain and surrounded by a parabola-shaped high-velocity anom...
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Strong, sharp, negative seismic discontinuities, velocity decreases with depth, are observed beneath the Pacific seafloor at ∼60 km depth. It has been suggested that these are caused by an increase in radial anisotropy with depth, which occurs in global surface wave models. Here we test this hypothesis in two ways. We evaluate whether an increase in surface wave radial anisotropy with depth is ...
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[1] An SH hybrid method is developed for calculating synthetic seismograms involving twodimensional localized heterogeneous structures. The hybrid method is a combination of analytic and numerical methods, with the numerical method (finite difference) applied in the heterogeneous region only and analytical methods applied outside the region. Generalized ray theory solutions from a seismic sourc...
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ژورنال
عنوان ژورنال: Geophysical Research Letters
سال: 2001
ISSN: 0094-8276
DOI: 10.1029/2000gl012553