Broadband Seismic Characterization of the Arabian Shield
Abstract
From November 1995 to March 1997 a total of nine broadband temporary stations were deployed across the Saudi Arabian shield. These stations consisted of STS-2 seismometers that recorded continuously at 40 sps on Refraction Technology RT72A-07 dataloggers. All installations were at bedrock sites. The results from our field deployment of nine portable broadband stations suggest that sites in the Arabian shield are extremely quiet with ground noise near or equal to the low-noise model in the frequency band from 1-10 Hz at the stations RAYN, AFIF, and HALM. All stations matched the low noise model for periods between 2 seconds and twenty second period. The low noise also contributes to the very low detection threshold at these stations of events with mb=3.5 at distances from 10 to 100 degrees. These stations appear to be among the best sites in the world for the properties of detection thresholds and ground noise levels. Seismograms from sources 10 degrees from the center of the network have unique characteristics which can be used to identity the source regions. Zagros events have a clear Pn and Sn arrivals with an observable Lg. Shallow events from the Arabian Sea have clear P, S, and surface waves but no discernible Lg phases. From the opposite direction, aftershocks from the Gulf of Aqaba have very weak P and S waves with very strong Lg phases.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 07, 1998
- Accession Number
- ADA358582
Entities
People
- Frank L. Vernon
- Jonathan Berger
Organizations
- Scripps Institution of Oceanography