ABSTRACT:

Historical documents, instrumentally recorded earthquakes during the past hundred years and the existence of many Geological faults all indicate that the region has a high potential of seismic activity. Although in the past centuries many destructive earthquakes occurred around Tehran region, but no major instrumentally recorded earhquake has been reported during thd past hundred yerars. Form ۱۹۷۵, ILPA seismic network in southwest of Thran has recorded many micro-earthquakes in Tehran region. In this study, all the recorded local events were extracted and analyzed. The results are in good agreements with the distribution of local faults. In some areas a kind of seismic gap can be understood. Taking into account the density of population in this region and  the economic and political conditions, it is necessary to carry on more extensive studies.