Phase velocity of the Arabian platform and the surface waves attenuation characteristics by wave form modeling

الملخص EN

The crustal structure beneath the Arabian platform has been investigated using available seismic records produced at the Riyadh (RYD) Station.

The phase velocities along 14 individual propagation paths were determined using the phase matched filter technique.

The phase velocities were found to increase from 2.3 km / s at 4 s to 4.1 km / s at 42 s.

Phase and group velocities were combined and used to invert for an S wave seismic crustal velocity structure.

The inversion process produced a model with B (the shear velocity) between 1.48-2.41 km / s in the top 3 km which repre¬sents the sedimentary cover rocks.

The upper crust B increases from 3.1 at 5 km to 3.67 km / s at 25 km depth.

The Lower crust is about 20 km thick, and its B increases rapidly from 3.76 km to 4.43 km / s.

The Moho discontinuity is at about 45 km depth with an average B of about 4.7 km / s.

The resulting shear velocity model was then combined with the Q model representative of the region, and synthetic seismograms were computed.

Comparison bet¬ween the observed data and theoretical results showed that the shear wave velocity model of the Arabian platform obtained in this study produces ex¬cellent match between recorded and computed seismograms.

This proce¬dure is suggested as a tool that can be used to study the attenuation charac¬teristics of the Arabian platform as well as the Arabian plate.