Official earthquake prediction procedure in Greece

2012

Abstract. New data were used to test the credibility of a previously reported power law relation between the stress drop of earthquakes and the lead time of precursory SES. Here, we found that the critical exponent of this power law is very sensitive and remains stable around 0.33 only for appropriate sets of data. This value is in full agreement with the reported one in literature for critical phenomena. That means this power law is not an artifact, but probably implies that real physical dynamic processes evolving to criticality are present in the pre-focal area when the SES is emitted. An attempt to advance the underlying physics of the interconnection of the stress drop and the lead time of the precursory SES is still in progress.

Section: Introductionmentioning

confidence: 99%

Stability of a power law relation between characteristics of earthquakes and electric precursors

2012

“…They are emitted from the pre-focal area when the tectonic stress reaches a critical value which also signals the entrance of the region into the last earthquake preparatory phase. SES are continuously monitored the last three decades by a network covering continental Greece and have been found to precede large earthquakes (Varotsos and Alexopoulos, 1984a, b;Varotsos et al, 1986Varotsos et al, , 1988Varotsos et al, , 1993Varotsos et al, , 2009). A possible model for SES generation which is based on the existence of point defects in solids Alexopoulos, 1977, 1981;Varotsos and Ludwig, 1978;Varotsos, 2007aVarotsos, , b, 2008) is as follows (e.g.…”

Section: Introductionmentioning

confidence: 99%

Testing the critical exponent in the relation between stress drop of earthquake and lead time of seismic electric signal

2012

Abstract. The application of new data in the power law relation between the stress drop of the earthquake and the lead time of the precursory seismic electric signal led to an exponent which falls in the range of the values of critical exponents for fracture and it is in excellent agreement with a previous one found by (Dologlou, 2012). In addition, this exponent is very close to the one reported by Varotsos and Alexopoulos (1984a), which interconnects the amplitude of the precursory seismic electric signals (SES) and the magnitude of the impending earthquake. Hence, the hypothesis that underlying dynamic processes evolving to criticality prevail in the pre-focal area when the SES is emitted is significantly supported.

“…Low frequency (<1 Hz) transient changes of the Earth's telluric field, the so called Seismic Electric Signals (SES) have been detected by a telemetric network of VAN stations installed at different sites in Greece, throughout the last 27 years (Varotsos and Alexopoulos, 1984a, b;Varotsos et al, 1988Varotsos et al, , 2004.…”

Section: Introductionmentioning

confidence: 99%

Temporal dependence of the selectivity property of SES stations in western Greece

2009

Abstract. The selectivity property of the SES stations, IOA, PIR and PAT in western Greece, based on reported precursory SES signals and associated large earthquakes (M w ≥5.4) that occurred from 1983 to the end of 2008, has been examined. Interesting temporal dependence of the sensitive ability of these stations has been unveiled. Physical mechanisms for the observed changes in selectivity might be related with tectonic and geodynamic events. For instance, selectivity for IOA exhibits a time dependence, for PAT probably is related to the activation of Wadati-Benioff zone while for PIR seems to be related to the specific tectonics of two confined areas such as the Cephalonia Transform Faulting zone in Ionian Sea and the southwestern part of the Hellenic Trench.