SAUDI-ARABIAN SEISMIC-REFRACTION PROFILE - A TRAVELTIME INTERPRETATION OF CRUSTAL AND UPPER MANTLE STRUCTURE

The crustal and upper mantle compression-wave velocity structure across the southwestern Arabian Shield has been investigated by a 1000-km-long seismic refraction profile. The profile begins in Mesozoic cover rocks near Riyadh on the Arabian Platform, trends southwesterly across three major Precambrian tectonic provinces, traverses Cenozoic rocks of the coastal plain near Jizan, and terminates at the outer edge of the Farasan Bank in the southern Red Sea. More than 500 surveyed recording sites were occupied, and six shot points were used, including one in the Red Sea. The crustal and upper mantle velocity structure of the Arabian Shield is interpreted as revealing a complex crust derived from the suturing of island arcs in the Precambrian. The Shield is currently flanked by the active spreading boundary in the Red Sea.