Document Type : Original Research Paper


1 Department of Geology, Faculty of Science, Golestan University, Gorgan, Iran

2 Road, Housing and Urban Development Research Center, Tehran, Iran


The 2017 Ezgeleh earthquake (Mw: 7.3), which occurred in the northwest of the Zagros, was followed by many aftershocks. The histogram of the monthly rate of aftershocks shows that, except for the first few months, the aftershock sequence did not follow the Omori law. Therefore, it is necessary to use more complex methods to investigate the aftershock sequence. In this research, the temporal multifractal method was used. The obtained results show that the temporal pattern of aftershocks has two short and long-scaling ranges. It seems that short and long ranges are related to the distribution of aftershocks within smaller clusters and the pattern of clusters in the aftershock sequence, respectively. These result showed that the pattern in the longer range is more heterogeneous than the shorter one. On the other hand, by removing the smaller aftershocks, the heterogeneity increases. It seems that the occurrence of several more significant aftershocks with a magnitude of more than 5 has caused an increase in the heterogeneity of the temporal pattern of the aftershock sequence. The results also show that the degree of inhomogeneity of the occurrence time of aftershocks is related to the spatial distribution pattern of aftershocks.


Main Subjects

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