Additional evidence on some relationship between seismic electric signals and earthquake source parameters

A b s t r a c t We provide recent experimental evidence which further supports the interrelation between the earthquake source parameters and the selectivity properties of Seismic Electric Signals. The cases of two major earthquakes with magnitudes larger than 6.0, that occurred in Greece during 2004–2005, are presented. A typical Seismic Electric Signals (SES) activity was recorded at Ioannina station (IOA) on 10 January 2004, as depicted in Fig. 1. Out of more than one hundred electric dipoles currently operating there, the following five dipoles are shown: The lower two channels (i.e., the channels No. 7 and 8) correspond to the two short dipoles (of length L = 50 m) installed at site C along the EW and NS direction, respectively (the sites of these electrodes can be found in Fig. 2b of Varotsos et al., 1996). The upper three channels (i.e., the channels No. 9, 10 and 11) refer to the three long dipoles L, L′ and L-I, the location of which is depicted in Fig. 2a of Varotsos et al., (1996). These long dipoles are directed almost NS; this is consistent with the fact that, when com