On rapid multidisciplinary response aspects for Samos 2020 M7.0 earthquake

Abstract

Following the M 7.0 earthquake that struck the Greek island of Samos and Turkey's western coast, causing extensive damage and casualties, we combined existing knowledge geodatabases concerning historical seismicity and rupture zones with seismological and geodetic measurements as well as with modelling and in situ observations, to provide an assessment of rapid response to the seismic event. In this paper, we demonstrate that in the frame of the gradual provision of information from the individual scientific disciplines, taking into account their respective potential and limitations, a multidisciplinary approach is able to address more efficiently rapid response issues in order to allow effective preliminary interpretation of the earthquake activity, even within the first 24 h of the event. It focuses on the assessment of the timely provision of information by each discipline, evaluating the access to primary data sources as well as the maturity of the techniques in terms of accuracy and rapid data processing. Within a period of less than a week, several constraints were partially compensated for, allowing the delivery of more robust results and interpretation. The study highlights the readiness level of the various domains that has been significantly improved over the past years, including rapid seismological solutions, systematic availability of free and open Earth Observation data and on-demand online processing through dedicated platforms. Their combination with routinely applied inversion modelling and timely in situ observation is leading to improved operational response levels. Supplementary Information The online version contains supplementary material available at 10.1007/s11600-021-00578-6.

Source modelling and stress transfer scenarios of the October 30, 2020 Samos earthquake: seismotectonic implications

“…Both models extend in the gap formed between clusters A and B of KOERI's spatial distribution (Figure 2), or between main epicentral cluster and cluster "1" of Cetin's et al (2020) spatial distribution (Figure 3), whereas our model extends mostly along the main epicentral cluster. Four different fault models, based on four different focal mechanisms, are proposed by Foumelis et al (2021). All four models diverge rather significantly from the quasi-E-W direction proposed in our and the other two models.…”

“…Other aftershock epicentral relocations followed afterwards (Papadimitriou et al, 2020;Foumelis et al, 2021;Karakostas et al, 2021), all ending up, more or less, in the same clusters recognition.…”

“…In order to define the source of the mainshock we combined all available seismological, geological and geodetic data, ending up to an emerging, N-dipping, normal dip-slip fault, just offshore and along the northern coast of Samos Island, compared with other fault models (Akkar et al, 2021;Foumelis et al, 2021;Ganas et al, 2020;Karakostas et al, 2021, Vallianatos andPavlou, 2021; USGS), which are either located further westwards, and/ or diverging significantly from the quasi-E-W orientation parallel to the northern coastline, or considered as a blind fault (Ganas et al, 2020). We modelled the dislocations on the nearby GPS/GNSS stations by applying the Okada (1992) dislocation solution formulae and compared them with the measured ones (Figure 5).…”

“…The modelled 2020 Samos mainshock source (see also Table 2) is represented by the yellowish rectangular (vertical projection of the fault plane on the map and red thick line its upper part). Several InSAR images have been also published (Papadimitriou et al, 2020;Foumelis et al, 2021;Ganas et al, 2021;Mavroulis et al, 2021) showing clear uplift of the north-northwestern coast of Samos Island and an abrupt change from uplift to subsidence near the centralnorthern coast, implying the possible emergence of the fault rupture, or a strand of it, on land. In other words, it is strongly supported that the rupture reached the surface and that was not very far from the coastline.…”

Exploring Cloud-Based Platforms for Rapid Insar Time Series Analysis

“…GEP 1 started as one of the ESA's Thematic Exploitation Platforms initiative, and is developed under a consortium led by Terradue, specifically aimed to support the exploitation of satellite data for geohazards. The platform provides a rich set of ready to use EO Data processing services for geohazards analysis and monitoring (Foumelis et al, 2021). One of the services in GEP is P-SBAS, Parallel Small BAseline Subset, developed by CNR IREA for time-series analysis of ground deformation (De Luca et al, 2015, Manunta et al, 2019.…”