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The Next-Generation Liquefaction database is a resource for the geotechnical hazard community. It is publicly available online under the following digital object identifier (DOI): 10.21222/C2J040. The database organizes objective liquefaction data into tables and fields (columns of information), with the relationships among the tables and fields described by a schema. The data are organized into tables pertaining to (1) sites, including geotechnical and geophysical site investigation data, surface geology information, and laboratory test data; (2) earthquake events, including source and ground motion information; and (3) observations of sites following events. The schema was vetted through community outreach efforts involving multiple workshops and meetings. Users can view the data, download existing data, and upload new data through a geographic information system (GIS)-based graphical user interface. Information uploaded to the database is reviewed by a database working group to verify consistency between uploaded data and source documents. The database is replicated in DesignSafe where users can interact with the data using Python scripts in Jupyter notebooks, view point cloud data using Potree, and interact with geospatial data using QGIS.

On 30 October 2020, an M w = 7.0 earthquake struck the Eastern Aegean Sea with considerable impact on Samos Island in Greece and the area of Izmir in Turkey. It was the most lethal seismic event in 2020 worldwide, and the largest and most destructive in the Aegean Sea since the 1955 earthquake that also affected both countries. The Civil Protection authorities in Greece and Turkey were effectively mobilized responding to the earthquake emergency. The main response actions comprised initial announcements of the earthquake and first assessment of the impact, provision of civil protection guidelines through emergency communication services, search and rescue operations,medical care, set up of emergency shelters and provisions of essential supplies, psychological support, as well as education, training activities and financial support to the affected population. From the comparison of the Civil Protection framework and the implemented response actions, it is seen that actions at both sides of the eastern Aegean Sea, followed a single-hazard approach in disaster management with similar response activities coordinated by a main Civil Protection agency, which was in close cooperation with the respective authorities at a national, regional and local level. Based on the presented information, it is concluded that the post-earthquake response and emergency management were satisfactory in both countries, with valuable lessons learnt ahead of the next major earthquake. To this end, many aspects can be further addressed to enhance community resilience and introduce a multi-hazard approach in (natural and man-made) disaster management.

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On October 30, 2020 14:51 (UTC), a moment magnitude (M) 7.0 (USGS, EMSC) earthquake occurred in the Aegean Sea. This paper presents the reconnaissance findings regarding the site effects on recorded strong ground motion intensities and duration, along with the resulting induced-structural damage in Izmir Bay and Samos Island, respectively. In all rock records, relatively high intensity long period rock spectral accelerations were observed in the mid to long period range of 0.5-1.5 s, which are attributed to the source, more specifically, to the slower rupture-mechanism of the event. These rich spectral intensities were further amplified by soil site effects and soil-superstructure resonance, leading to two to six times amplified overall responses and prolonged seismic shaking durations, more pronounced in Bayrakli and other Izmir Bay sites in Turkey. However, these amplified and prolonged excitations are still below design basis earthquake levels, which addresses the lack of proper structural design and construction deficiencies, as the underlying causes for the collapse to heavy damage performance of 795 buildings. On the other hand, although located only about 10 km from the rupture (22 km from the epicenter) and within the near fault zone, the town of Vathy on Samos Island (Greece) was rather lightly affected by the earthquake, with relatively few collapsed or heavily damaged buildings, partially attributed to the low height/low weight of structures in the area. However, a concentration of damage in low-rise buildings in Ano Vathy hill is considered indicative of a combination of coupled valley and topography effects on the strong motion. This event once again addressed the need to develop region-specific zonation and provisions, when more general code practices are proven to be inadequate to assess these extreme site effects.