maryam safarshahi - institute of geophysics university of tehran
hosein hamzehloo - internation institute of earthquake engineering and seismology iran
mehdi rezapour - institute of geophysics university of tehran
fereidoon sinaeian - building and housing research center iran

the quality factor of seismic waves is closely related to the seismicity and regional tectonic activity of a particular area . December 20, 2010 earthquake with magnitude of MW=6.5 and january 27,2011 earthquake with magnitude of Mw-6.2 national earthquake information center NEIC occurred in rigan region southeasterniran. these earthquakes recorded on the 24 and 8 stations of the iran strong motion network ISMN installed by BHRC with maximum accelerations equal to 124cm/s2 for the transverse component recorded at rigan station and 195 cm/s2 for the longitudinal component recorded at sarzeh station respectively in this research the the quality factor of shear waves Qsin rigan region has been estimated using the strong motion data of rigan earthquakes 2010&2011 with epicentral distance of less than 100 km.

quality factor , spectral decay method , rigan earthquakes , iran.