Microseismicity and crustal structure of the transition zone Zagros-Makran based on the data of a local dense temporary seismological network  Fulltext 

[ F. Yamini Fard ] - Laboratoire de Géophysique Interne et Tectonophysique de Grenoble (LGIT), Université Joseph-Fourier, Grenoble, France, (2) International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, I.R. Iran

خلاصه مقاله:

To understand the transition zone of the Zagros-Makran, we installed a dense seismological local temporary network in the region of Minab for two months. During this field experiment we recorded 500 microearthquakes that show a significant seismic activity at the transition zone and no seismic activity east of the Jiroft fault. We also observe an important activity in north of the Zendan-Minab fault system. The depth distribution of the microearthquakes shows a lack of the seismicity in the sedimentary layer which is 11 km thick and the depth increase to the northeast from 15 km to 30 km. Focal mechanisms determined by P first polarities show thrust and right-lateral strike-slip mechanisms. We do not observe any evidence of strain partitionning around the Zendan-Minab fault system but rather observe two families of mechanisms distributed in depth. P wave teleseismic travel-time residuals confirm an important variation of the velocity structure across Zendan-Minab fault system.