Satellite-Observed Thermal Anomalies and Deformation Patterns Associated to the 2021, Central Crete Seismic Sequence

Nowadays, there has been a growing interest in understanding earthquake forerunners, i.e., anomalous variations that are possibly associated with the complex process of evolution. In this context, Robust Satellite Technique was coupled 10 years (2012–2021) daily night-time MODIS-Land Surface Temperature remote sensing data to detect thermal anomalies likely related 27 September 2021, strong onshore magnitude Mw6.0 occurring near Arkalochori village Central Crete, Greece. Eight intense (signal-to-noise ratio > 3) and infrequent, quite extensive, temporally persistent signal transients were detected characterized as pre-seismic anomalies, while one transient identified co-seismic effect on day main tectonic event. The dataset combined parameters such active faults fault density, seismogenic zones ground displacement maps produced using Sentinel-1 satellite imagery Interferometric Synthetic Aperture Radar technique. Regarding anomaly September, its greatest portion observed over footwall part where significant subsidence up 20 cm exists. We suggest connected gas release which happens due stress changes is controlled by existence lines density faults, even if alternative explanations could not be excluded.