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We estimate lithospheric velocity structure for the Arabian shield by modeling receiver functions and Love and Rayleigh group velocities from event recorded by the 1995-1997 Saudi Arabian Portable Broadband Deployment. Receiver functions are primarily sensitive to shear-wave velocity contrast and vertical travel times and surface-wave dispersion measurements are sensitive to vertical shear-wave velocity averages, so that their combination bridge resolution gaps associated with each individual data set. We incorporate depth-dependent smoothness constraints on the resulting velocity models utilizing a jumping inversion technique. Additional constraints for the upper mantle are placed during inversion to complement those provided in our data set. Our results show a 32-36 km thick crust consisting of a 10-12km thick upper crust containing a rapid velocity increase, a rather constant velocity, a rather constant velocity lower crust of 3.84\(+-O.04 km/s overlayed by a significant velocity gradient above 16-22 km depth. The upper mantle material is shown to have shear velocities ranging from 4.3 to 4.6km/s and the crust-to-mantle transition is imaged as a gradational transition zone (4-12 km thick) rather than a sharp discontinuity. Evidence for lateral variations in both crust and upper mantle is observed at some stations as well.

High resolution total and indium differential atomic pair distribution functions (PDFs) for In_(0.5)Ga_(0.5)As alloys have been obtained by high energy and anomalous x-ray diffraction experiments, respectively. The first peak in the total PDF is resolved as a doublet due to the presence of two distinct bond lengths, In-As and Ga-As. The In differential PDF, which involves only atomic pairs containing In, yields chemical specific information and helps ease the structure data interpretation. Both PDFs have been fit with structure models and the way in that the underlying cubic zinc-blende lattice of In_(0.5)Ga_(0.5)As semiconductor alloy distorts locally to accommodate the distinct In-As and Ga-As bond lengths present has been quantified.

We estimate lithospheric velocity structure for the Arabian shield by modeling receiver functions and Love and Rayleigh group velocities from events recorded by the 1995-1997 Saudi Arabian Portable Broadband Deployment. Receiver functions are primarily sensitive to shear-wave velocity contrasts and vertical travel times and surface-wave dispersion measurements are sensitive to vertical shear-wave velocity averages, so that their combination bridge resolution gaps associated with each individual data set. We incorporate depth-dependent smoothness constraints on the resulting velocity models utilizing a jumping inversion technique. Additional constraints for the upper mantle are placed during inversion to complement those provided in our dataset.

We estimate lithospheric velocity structure for the Arabian shield by modeling receiver functions and Love and Rayleigh group velocities from events recorded by the 1995-1997 Saudi Arabian Portable Broadband Deployment. Receiver functions are primarily sensitive to shear-wave velocity contrasts and vertical travel times and surface-wave dispersion measurements are sensitive to vertical shear-wave velocity averages, so that their combination bridge resolution gaps associated with each individual data set. We incorporate depth-dependent smoothness constraints on the resulting velocity models utilizing a jumping inversion technique. Additional constraints for the upper mantle are placed during inversion to complement those provided in our dataset.