Earthquakes are usually clustered in both time and space and, within each cluster, the event of highest magnitude is conventionally identified as mainshock, while foreshocks aftershocks events that occur before after it, respectively. Mainshocks earthquakes considered classical formulation probabilistic seismic hazard analysis (PSHA), where contribution neglected. In fact, it has been shown pos...

Most reinforced concrete (RC) frames would exhibit different degrees of damage after mainshock excitations, and these mainshock-damaged RC (MD-RC) are highly vulnerable to severe or even complete collapse under aftershock excitations. In the present study, effectiveness utilizing soft steel damper (SSD) as a passive energy dissipation device for seismic retrofitting MD-RC frame actions was inve...

Four large earthquakes occurred in 1980 in a seismic gap near the Loyalty Islands in the New Hebrides. At 3:25 UT on October 24 an event with M, = 6.7 initiated the sequence. Three events, M, = 6.7, 7.2, and 6.5, followed on the next day. We investigated this sequence by using the seismicity, first-motion, and wavefonn data and long-period surface waves. The first-motion data constrain one of e...

Estimates of the tectonic stress state including loading rate and magnitude of background stress are derived from the spatial and temporal distribution of Loma Prieta aftershocks. This technique was previously applied to the Landers aftershock sequence Gross and Kisslinger, 1997] and is based upon the seismicity model of Dieterich 1994]. Dieterich's theory suggests that background seismicity sh...

[1] The 27 February 2010 Maule, Chile (Mw=8.8) earthquake is one of the best instrumentally observed subduction zone megathrust events. Here we present locations, magnitudes and cumulative equivalent moment of the first 2 months of aftershocks, recorded on a temporary network deployed within 2 weeks of the occurrence of the mainshock. Using automatically-determined onset times and a back projec...