Study of the Statistical Properties of Kaki Aftershocks in Bushehr Province, Iran, April 09, 2013

An Earthquake occurred with Mw 6.3 at 11:52 UTC in the 9 April 2013, near the city of Khurmoj and kaki in Bushehr province in southern Iran. The earthquake approximately killed 37, injured 950 and left 1000 people homeless and damaged 500 more houses in nearby villages. This event was felt in Bushehr but there is no damages in nuclear power plant of Bushehr (about 80 Km NW of the epicenter of event). In this study, the aftershock sequence of Bushehr earthquake was used to considering statistical properties. The aftershock sequences of this earthquake contains about 4 month‘s time period, that is from the time of the mainshock (April 9, 2013) until August 10, 2013. For this purpose, we analyzed bvalueof frequency-magnitude distribution of earthquake and other parameters. The b-value and a-value are calculated as 0.948±0.07 and 5.55, respectively for the aftershocks of Kaki earthquake. Aftershock activity decreased with time in accordance with the modified Omori law, with p values close to 1.01. We considered variations of b-value before and after the mainshock, the lower b-values before mainshock confirmed thata great stress had accumulated in the region. On the other hand, after the mainshock the higher p and b-value is related to lower stress in the area.

کلیدواژه ها:

Kaki earthquake ، aftershock ، Frequency-magnitude distribution ، Omori law ، Bushehr