Power law relationship between parameters of earthquakes and precursory electrical phenomena revisited

Abstract

Abstract. The power law relation between the stress drop of "non thrust" earthquakes and the lead time of precursory Seismic Electric Signals (SES), obtained by Dologlou (2008a), has been tested by using additional data from the most recent earthquake that occurred on 8 June 2008, in Andravida, NW. Peloponnesus, Greece and from two other destructive earthquakes that occurred in the past in Ionian sea. A critical exponent α=0.33 is derived which is close to the one (e.g. 0.29) reported by Dologlou (2008a). The above preliminary result strengthens the hypothesis that probably signatures of criticality are present in the earthquake preparation and precursory SES processes and that both phenomena are governed by same physics.

Features of criticality in precursory seismic electric signals and earthquakes in Greece

“…We note that event nos. 11, 13 and 15 are always excluded from this relation for reasons explained in detail (Dologlou et al, 2008;Dologlou, 2008aDologlou, , 2009). The new derived exponent value is α = 0.330 ± 0.01 (Fig.…”

“…where r is the radius for a circular fault and it is estimated by applying the aftershock area technique (Kiratzi et al, 1985(Kiratzi et al, , 1991 as it is described in detail by Dologlou (2009). The aftershock area S = π r 2 with dimensions L × W = (36 × 11) km 2 , where L is the length and W the width (Table 1), is defined from the cluster formed by the distribution of the epicentres of the aftershock sequence ( Fig.…”

“…Second, in Greece a SES activity was recorded in a station located in northern Greece (Varotsos et al, 2012) which was followed by a magnitude 5.7 earthquake in northern Aegean sea. This finding enables the examination on whether the credibility of a power law relation with a critical exponent between the earthquake stress drop (which is the difference between the stress state at a point on a fault before and after the occurrence of the earthquake) and the SES lead time found by Dologlou (2009Dologlou ( , 2010Dologlou ( , 2012a is preserved when these new data are introduced. This critical exponent based on a large amount of data of earthquakes and associated SESs is subjected to a continuous updating and seems to exhibit a remarkable stability and universality.…”

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

“…The aforementioned interconnection of SES lead time t and earthquake stress drop σ through a power law relation with an exponent value of 0.33 has been found by Dologlou (2009Dologlou ( , 2010 using data from 1981 to 2010 from precursory SES signals and large earthquakes (see Table 1, Dologlou, 2010), for which Brune's stress drop (Brune, 1970(Brune, , 1971) values were either reported or derived through a special technique based on the dimensions of the aftershock area and seismic moment (Kiratzi et al, 1991). Here, we deal with the largest earthquakes that occurred in Greece within 5 months after the detection of new SES activity, which was recorded at PIR station (blue triangle in Fig.…”

“…Precisely, a robust power law relation with a critical exponent of 0.33 has been found to interrelate the lead time t (which is the time difference between the SES emission and the associated earthquake occurrence) and the stress drop (which is the difference between the stress state at a point on a fault before and after the occurrence of the earthquake) of the forthcoming earthquake (Dologlou, 2009(Dologlou, , 2010.…”