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On March 3, 2021 a Mw=6.3 shallow earthquake occurred in the mountainous region of Damasi, about 20 km to the northwest of Larisa, Thessaly, central Greece, in a region of active crustal extension but of low strain. This event was followed by a Mw=6.0 shallow earthquake on March 4, 2021 about 12 km to the northwest, inside the sedimentary basin of the Titarisios river. On March 12, 2021 a third event of Mw=5.6 occurred 7 km further towards NNW, near the NW edge of the basin. All events show normal-slip kinematics as indicated by the moment tensor solutions, with minor strike-slip components. Because of the shallow depth of the events it was possible to map the surface deformation using InSAR. The preliminary results from InSAR show three main lobes of subsidence, partially overlapping. The deformation pattern indicates the activation of three normal faults, previously unknown in this part of Thessaly. The earthquakes generated numerous secondary phenomena with vast areas of alluvial deposits exhibiting spectacular liquefaction features. No tectonic ruptures were found in the cases of events 2 and 3, however a series of sporadic, NW-SE striking surface breaks were found on the mountains north of village Zarko that are aligned with the vanishing gradient of the interferometric phase of the 1st event. &nbsp

We use optical satellite data to map the co-seismic displacements for the Mw=7.5 strike-slip earthquake of 28 September 2018 in Palu, Sulawesi, Indonesia. This was a strike-slip faulting event at shallow depth that occurred within the interior of the Molucca Sea microplate, which is part of the Sunda tectonic plate. Using optical image correlation from Sentinel-2 and Planet imagery, we mapped the surface rupture extent of the earthquake and calculated the co-seismic offsets. Before- and after- the earthquake image acquisitions were analyzed using MicMac software and the MPIC-OPT service on the ESA Geohazards TEP platform. Our results include the mapping of a) the detailed trace of the ruptured fault at the southern part of the region (Palu segment) and b) a more complex deformation pattern at the northern part of the rupture. Analysis of the horizontal displacement field and sequential profiles across the fault also enabled mapping of the fault zone complexity, secondary faulting, fault zone width and large co-seismic gravitational phenomena. A mean displacement of 3-5 metres was calculated for a total earthquake rupture length of more than 140 km. Our results agree with the focal mechanism solution for the earthquake which indicates that the rupture occurred on a left-lateral, north-south striking fault. The significance of this event is also associated with the severity of the tsunami impact attributed to a strike slip fault. Further investigation is necessary to determine the source of the tsunami as primarily tectonic or due to another mechanism although a more complex mechanism is likely., Report submitted to EMSC on 19 October 2018 12:00 UTC

On March 3, 2021 a Mw=6.3 shallow earthquake occurred in the mountainous region of Damasi, about 20 km to the northwest of Larisa, Thessaly, central Greece, in a region of active crustal extension but of low strain. This event was followed by a Mw=6.0 shallow earthquake on March 4, 2021 about 12 km to the northwest, inside the sedimentary basin of the Titarisios river. On March 12, 2021 a third event of Mw=5.6 occurred 7 km further towards NNW, near the NW edge of the basin. All events show normal-slip kinematics as indicated by the moment tensor solutions, with minor strike-slip components. Because of the shallow depth of the events it was possible to map the surface deformation using InSAR. The preliminary results from InSAR show three main lobes of subsidence, partially overlapping. The deformation pattern indicates the activation of three normal faults, previously unknown in this part of Thessaly. The earthquakes generated numerous secondary phenomena with vast areas of alluvial deposits exhibiting spectacular liquefaction features. No tectonic ruptures were found in the cases of events 2 and 3, however a series of sporadic, NW-SE striking surface breaks were found on the mountains north of village Zarko that are aligned with the vanishing gradient of the interferometric phase of the 1st event., Partially funded by the joint research - industry project MIS-5070928, financed by the EU and the Greek Government