Writers : Sadeghi, H.; Nasiripour, B.; Kaviani, A.; Takenaka, H.
Publishing Year : 1387

Abstract :

The Khorasan Region is one of the active seismic zones in Iranian plateau, which is located between central Iran and Kopet-Dagh zones. We study the crustal thickness (H) and Vp/Vs ratio (k) in Mashhad, capital of Razavi Khorasan province, by the receiver function method. This study uses recorded teleseismic events in the three broadband stations of Khorasan Seismic Network, Earthquake Research Center of Ferdowsi University of Mashhad. In the radial receiver function, first phase following direct P-wave that has relatively larger amplitude is the Moho P to S conversion (Ps), which is distinguished clearly in the stations. Therefore by picking up arrival time of P to S conversion on the radial receiver function and from time to depth relation for this phase and on the bases of IASPEI91 velocity reference model, the crustal thickness under each station can be estimated. Then, in order to process a large amount of teleseismic events, to reduce the effect of lateral structural variations, calculation of variance of H and k, and the lake of need for picking arrival times of P to S conversions; we use the Zhu and Kanamori s stacking algorithm (Zhu and Kanamor, 2000). On the bases of this method, the crustal thickness in the study area is 51±3 km and the Vp/Vs ratio is 1.65±0.06 on average.

Subject List : moho depth