SERKAN ÖZTÜRK
Abstract
A statistical analysis on the aftershock sequence of January 24, 2020 Sivrice-Elazığ (Turkey) earthquake was performed by using well-known parameters such as b-value and p-value. Aftershock catalog was taken from KOERI and includes 4458 aftershocks in one year after the mainshock. b-value was computed as 0.82±0.02 by considering the magnitude of completeness value as Mcomp=1.9. It is smaller than typical b1 and this small b-value may be caused by the abundance of aftershocks with ML4.0. p-value was estimated as 0.80±0.02 with a c-value=0.279±0.068 and it is smaller than the global p1. This low p-value may due to the relatively slow decay rate of the aftershock activity. The lowest b-values were found in the north, south and southwest direction of the mainshock including Pütürge and Erkenek segments. These findings indicate that there is a relation between the largest aftershocks and the lowest b-values. The highest p-values were observed in and around the mainshock including Pütürge segment. The regions with the smallest b-value and the largest p-value have large stress and coseismic deformation, respectively. Stress variations and coseismic deformation are highly effective on the b-value and p-value variations. Thus, earthquake hazard may be evaluated with the aftershock hazard parameters and spatio-temporal analysis of aftershocks is suggested for a preliminary assessment after the mainshock.
Keywords
Sivrice-Elazığ aftershock sequence, Gutenberg-Richter Relation, Modified Omori Law, Aftershock hazard.
