ATTENUATION LAW OF STRONG GROUND MOTIONS FOR IRANIAN EARTHQUAKES

A statistical analysis of occurrences of the large Persian earthquakes reveals that at the territory of Iran practically for each decade an earthquake with magnitude Ms į ۷ has to be expected (Rama zi, ۱۹۹۴). The last such earthquake was Rudbar earthquake of ۲۰ June ۱۹۹۰ (M$=۷.۷). Strong ground motions belonging to its main shock were recorded by more than ۲۰ accelerographs over the shaken a rea,In this paper results of a processing of above mentioned records and some other selected records registered by the Iranian strong ground motion network will be presented. The obtained empirical relationships between peak particle ground acceleration, earthquake magnitude and the nearest distance from causative faults will be compared with results proposed by Boore-Joyner (۱۹۸۲) and Campbell (۱۹۸۱).