Temporal properties of seismicity and largest earthquakes in SE Carpathians

Abstract

Abstract. In order to estimate the hazard rate distribution of the largest seismic events in Vrancea, South-Eastern Carpathians, we study temporal properties of historical and instrumental catalogues of seismicity. First, on the basis of Generalized Extreme Value theory we estimate the average return period of the largest events. Then, following Bak et al. (2002) and Corral (2005a), we study scaling properties of recurrence times between earthquakes in appropriate spatial volumes. We come to the conclusion that the seismicity is temporally clustered, and that the distribution of recurrence times is significantly different from a Poisson process even for times largely exceeding corresponding periods of foreshock and aftershock activity. Modeling the recurrence times by a gamma distributed variable, we finally estimate hazard rates with respect to the time elapsed from the last large earthquake.

Analysis of the b, p values, and the fractal dimension of aftershocks sequences following two major earthquakes in central Himalaya

“…For the Gorkha earthquake of 2015, D c = 1.66 was estimated for 820 aftershocks (2.7 < M < 7.3) recorded from 25 April to 12 November [ 78 ]. A temporal fractal dimensions is especially useful to understand the dynamic evolution of seismic processes [ [79] , [80] , [81] ] and in the preceding work [ 82 ] it was estimated 0.395 ± 0.0027 from the analysis of 350 aftershocks of Gorkha earthquake located between 84.3° to 87.0° longitude and 27.3° to 28.5° latitude. Furthermore, the box counting fractal dimension ≥1.74, and ≥1.82 were estimated respectively for western Nepal and eastern Nepal [ 83 ], and the correlation fractal dimension 1.89 ± 0.02, 1.76 ± 0.01, and 1.85 ± 0.02 were estimated respectively for the western Nepal, central Nepal and eastern Nepal [ 84 ].…”

Vrancea slab earthquakes triggered by static stress transfer

“…Given that intermediate-depth seismicity in Vrancea is clustered (Purcaru, 1979;Byrdina et al, 2006;Hurukawa et al, 2008) there may be some basis for putting forward arguments for recurrence of strong earthquake activity based on the stress transfer results. We show a seismicity map in Fig.…”