The monitoring of statistical network properties could be useful for the short-term hazard assessment of the occurrence of mainshocks in the presence of foreshocks. Using successive connections between events acquired from the 10 earthquake catalogue of INGV for the case of the L’Aquila (Italy) mainshock (Mw = 6.3) of 6th April 2009, we provide evidence that network measures, both global (e.g. ...

We present an analytical solution and numerical tests of the epidemic-type aftershock (ETAS) model for aftershocks, which describes foreshocks, aftershocks and mainshocks on the same footing. In this model, each earthquake of magnitude m triggers aftershocks with a rate proportional to 10. The occurrence rate of aftershocks triggered by a single mainshock decreases with the time from the mainsh...

The state of tectonic stress in the epicentral area of the 17 January 1994, Northridge earthquake (Mw 6.7) is investigated by applying a stress inversion method to P-wave polarity data from earthquakes in Northridge from July 1981 to January 1994 and from the Northridge aftershocks during January 1994 to December 1995. A 3-D crustal model is used to trace the rays taking off from the hypocenter...

A mainshock is usually accompanied by a group of ground motions. In many design codes, the effects seismic sequences have been neglected or underestimated. Aftershocks can increase structural damage even cause failure. The current study evaluated behavior rehabilitated and as-built reinforced concrete (RC) structure under real scaled mainshock-aftershocks using nonlinear analysis. Verification ...

Despite previous observations that aftershocks lie preferentially along the fault planes of mainshocks, many branching models for earthquake occurrences do not directly incorporate information on the moment tensors of mainshocks in forecasting the spatial distribution of aftershocks, or do so in a very simplistic way using spatial kernels which have not been rigorously tested on earthquake data...

SUMMARY The Gutenberg–Richter (GR) and the Omori–Utsu (OU) law describe earthquakes’ energy release temporal clustering are thus of great importance for seismic hazard assessment. Motivated by experimental results, which indicate stress-dependent parameters, we consider a combined global data set 127 main shock–aftershock sequences perform systematic study relationship between shock-induced str...

The effect of aftershocks on the fragility single-story masonry structures is investigated using probabilistic seismic demand analysis Finite element models an unreinforced (URM) structure and a confined (CM) are established their response characteristics when subjected to mainshock, aftershock, mainshock-aftershock sequence then comparatively investigated. effects use confining members studied...

Abstract This paper presents the fragility assessment of non-seismically designed steel moment frames with masonry infills. The considered effects multiple earthquakes on damage accumulation frames, which is an essential part modern performance-based earthquake engineering. Effects aftershocks are particularly important when examining damaged buildings and making post-quake decisions, such as t...

We demonstrate that the statistics of earthquake data in the global Centroid Moment Tensor (CMT) and National Earthquake Information Center (NEIC) catalogs and local California Council of the National Seismic System (CNSS) catalog are consistent with the idea that a single physical triggering mechanism is responsible for the occurrence of aftershocks, foreshocks, and multiplets. Specifically, w...

The state of stress in the Eastern California Shear Zone (ECSZ) changed significantly because of the occurrence of the 1992 Mw 6.1 Joshua Tree and the Mw 7.3 Landers earthquakes. To quantify this change, focal mechanisms from the 1975 Galway Lake sequence, the 1979 Homestead Valley sequence, background seismicity from 1981 to 1991, and the 1992 Landers sequence are inverted for the state of str...