We investigate the thickness and seismic velocity structure of the Rukwa Rift crust by modeling seismograms from the 1994 Mw 5.9 Rukwa earthquake and teleseismic receiver functions recorded on a broadband seismic station at the southeastern end of the rift. Two methods have been used to model receiver functions, Hstacking and waveform inversion, yielding Moho depth estimates of 34 ± 2 km (Hstac...

We located the aftershocks of the 4 February 1975 Haicheng, China, aftershock sequence using an arrival time difference (ATD) simultaneous inversion method for determining the near-source (in situ) velocity and the location of the aftershocks with respect to a master event. The aftershocks define a diffuse zone, 70 km x 25 kin, trending west-northwest, perpendicular to the major structural tren...

Seismic refraction profiles recorded layer. Crustal subsidence and periodic basaltic along the eastern Snake River Plain (ESRP) in southeastern Idaho during the 1978 YellowstoneSnake River Plain cooperative seismic profiling experiment are interpreted to infer the crustal velocity and attenuation (Q-i) structure of the ESRP. Travel-time and synthetic seismogram modeling of a 250 km reversed ref...

The stratigraphy of the South-Pole Aitken basin (SPA) interior is consistent with that of a massive impact melt sheet that differentiated to form cumulates. Spectroscopic and geophysical constraints on the stratigraphy of SPA suggest a 12.5 km thick layer of norite above ultramafic pyroxenite and dunite layers. A similar stratigraphy is produced from differentiation by crystal settling of a 50 ...

[1] PS converted waves observed near Ancona on the Adriatic coast of central Italy, as revealed by teleseismic receiver functions (RFs), vary with earthquake backazimuth and epicentral distance in a manner consistent with a 1-D anisotropic seismic structure. Using reflectivity calculations, we develop a profile of anisotropic seismic velocity through the Adriatic lithosphere at this locality. W...

The propagation of seismic waves through Earth can now be modeled accurately with the recently developed spectral-element method. This method takes into account heterogeneity in Earth models, such as three-dimensional variations of seismic wave velocity, density, and crustal thickness. The method is implemented on relatively inexpensive clusters of personal computers, so-called Beowulf machines...

Crustally-derived granites may be generated in a variety of tectonic settings, but whatever the ultimate causse of heating crustal thickening, crustal extension, enhanced heat flux from the mantle, or magmatic advection by mantle-derived melts crustal melting likely occurs in a dynamic environment. Under these conditions deviatoric stress acting on an anisotropic crustal source region will lead...

iran is situated in one of the world's seismic regions and the possibility of destructive earthquakes in most regions of the country has given great significance to recognition of iranian seismic nature from a seismic and seismotectonic standpoint. study of the crust and upper mantle velocity structure in the iranian plateau provides better understanding of its evolution and tectonic histo...