Assessing of the robust satellite techniques (RST) in areas with moderate seismicity

The RST (Robust Satellite Technique) approach has been applied to tens of seismic events occurred all around the world, in various geo-tectonic settings and with a wide range of magnitudes (from 4.0 to 7.9). It turned out to be a reliable tool to investigate possible relations between earthquake occurrence and space-time fluctuations of Earth’s emitted TIR radiation observed from satellite. Before now was however difficult to find regions joining the occurrence of high magnitude earthquakes (to be considered for validation purposes) with sufficiently long, seismically unperturbed, periods to be considered for confutation purposes (i.e. to verify the absence of significant TIR space-time fluctuations in absence of earthquakes). In this paper, the RST technique has been tested, for the first time, over an area characterized by moderate seismic activity: the Caucasian region. The case of Mestia Tianeti (Georgia) earthquake (23rd October 1992, M=6.3) was selected as test case. TIR anomalies were detected in some spatial relation with tectonic lineaments of the area since 2nd October (also if stronger intensity anomalies appeared the day after). Moreover, the confutation phase, performed on a period with no seismic events with magnitude greater than 3 (October 1999), confirmed the absence of TIR anomalies having characteristics of spatial extension and persistence in time like those observed instead in the pre-seismic time.