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[1] Stacking of approximately 1500 radial receiver functions recorded at about 80 broadband seismic stations deployed in southern Africa reveals systematic spatial variations in the ratio of crustal P and S wave velocities (F), crustal thickness (H), and the amplitude of the converted Moho phases (R). The eastern Zimbabwe and the southern Kaapvaal cratons(More)
Seismic anisotropy from the southern African mantle has been inferred from shear-wave splitting measured at 79 sites of the Southern African Seismic Experiment. These data provide the most dramatic support to date that Archean mantle deformation is preserved as fossil mantle anisotropy. Fast polarization directions systematically follow the trend of Archean(More)
[1] Seismic velocity discontinuities within the top 1000 km of the Earth beneath southern Africa are imaged by stacking about 1300 source-normalized broadband seismograms recorded by the Southern African Seismic Experiment. The Moho, 410, and 660 kilometer discontinuities are clearly detected. The mean mantle transition zone thickness is 245 km, essentially(More)
Shear-wave splitting (SWS) analyses are essential in understanding the structure and dynamics of the Earth's deep interior. While splitting measurements have excellent horizontal resolution relative to other anisotropy-measuring techniques, their vertical resolution is low due to the steep incidence angle of the seismic phases used by the analyses. Here,(More)
New shear-wave splitting measurements at permanent broadband seismic stations in the south-central United States reveal the orientation and degree of polarization of mantle fabrics, and provide constraints on models for the formation of these fabrics. For stations on the stable North American craton, correspondence between observed polarization direction of(More)
The observed seismic anisotropy of the southern African mantle from both shear-wave splitting and surface wave observations provides important constraints on modes of mantle deformation beneath this ancient continent. We find that the mantle anisotropy beneath southern Africa is dominated by deformational events in Archean times occurring within the(More)
[1] A total of 361 SKS and five local S wave splitting measurements obtained at global and regional seismic network stations in NE China and Mongolia are used to infer the characteristics of mantle fabrics beneath northeast Asia. Fast polarization directions at most of the stations in the western part of the study area are found to be consistent with the(More)
[1] Shear wave splitting is a robust tool to infer the direction and strength of seismic anisotropy in the lithosphere and underlying asthenosphere. Previous shear wave splitting studies in the Afar Depression and adjacent areas concluded that either Precambrian sutures or vertical magmatic dikes are mostly responsible for the observed anisotropy. Here we(More)
[1] Shear wave splitting measurements using teleseismic PKS, SKKS, and SKS phases recorded by station LSA on the southern part of the Lhasa Terrane of the Tibetan Plateau reveal significant azimuthal anisotropy with a splitting time of up to 1.5 s, a conclusion that is contradictory to previous studies which suggested isotropy or weak anisotropy. In(More)