Ground Motion Characteristics of 2012 Ahar-Varzaqan (Iran)

M Bastami, M.R Soghrat


Aftershocks of strong earthquakes are important because they usually occurred with a large magnitude
which can cause building collapse if buildings have been damaged due to the mainshock. One of the
challenges in aftershock studies is recognition of the differences between the characteristics of the
mainshock and its aftershocks. More than 20 aftershocks have been reported with magnitude more than
4 for the 2012 Ahar-Varzaqan twin earthquakes with magnitudes of 6.4 and 6.3. In this study, it is tried
to find the relationship between spectral acceleration of the first major earthquake and the next events.
Moreover, ground motion parameters such as predominant period and mean period are used to check
the possible similarity and correlation between a pair of events. The results show that the selected
parameters in the main events have a good correlation with each other. Mean period of the aftershocks
have a good correlation with the mainshocks unlike the parameters same as predominant period and
significant duration which they do not show a specific trend between mainshock and its aftershocks.
Finally, a scaling model is proposed to predict the response spectrum of an aftershock motion
compatible with the design spectrum of the main shock motion at the same station.

Full Text:



  • There are currently no refbacks.