Seismic quiescence patterns and earthquake prediction research : Testing hypotheses for Greece and China

Abstract: The main aim of this investigation is to evaluate the most well known hypotheses and models in earthquake prediction research. For this reason we investigate the "localized" seismic quiescence hypothesis using the Z value griding method as well as the recently introduced Seismolap hypothesis of "extended" seismic quiescence.The results indicate that precursory seismic quiescence has preceded crustal main shocks in China and Greece and also that aseismic quiescence can be attributed to "silent earthquakes " such as creep events in subduction zones. The application of the Z-value method in investigating the recent seismic quiescence regime in Greece has given indications of three areas in Greece where significant quiescence is observed and which also are candidate areas for strong earthquakes according to their previous seismic history.Recently, the Gulf of Corinth in Central Greece has been appointed as an official multiparameter site for earthquake prediction research by the European Council and in this framework, magnetotelluric and seismological investigations revealed the presence of fluids in the Earth's crust that are mainly responsible for the observed seismic and electromagnetic anisotropy which correlates well with the local stress field as revealed from GPS measurements. In addition, the spectral fitting method was used on digital short period data from this region in order toobtain dynamic source parameters from local earthquakes and also to determine scaling relations using two different earthquake source models.