We provide a database of the coseismic geological surface effects following the Mw 6.5 Norcia earthquake that hit central Italy on 30 October 2016. This was one of the strongest seismic events to occur in Europe in the past thirty years, causing complex surface ruptures over an area of >400 km2. The database originated from the collaboration of several European teams (Open EMERGEO Working Group; about 130 researchers) coordinated by the Istituto Nazionale di Geofisica e Vulcanologia. The observations were collected by performing detailed field surveys in the epicentral region in order to describe the geometry and kinematics of surface faulting, and subsequently of landslides and other secondary coseismic effects. The resulting database consists of homogeneous georeferenced records identifying 7323 observation points, each of which contains 18 numeric and string fields of relevant information. This database will impact future earthquake studies focused on modelling of the seismic processes in active extensional settings, updating probabilistic estimates of slip distribution, and assessing the hazard of surface faulting.

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We applied a joint survey approach integrating time domain electromagnetic soundings and single‐station ambient vibration surveys in the Middle Aterno Valley (MAV), an intermontane basin in central Italy and the locus of the 2009 L'Aquila earthquake. By imaging the buried interface between the infilling deposits and the top of the pre‐Quaternary bedrock, we reveal the 3‐D basin geometry and gain insights into the long‐term basin evolution. We reconstruct a complex subsurface architecture, characterized by three main depocenters separated by thresholds. Basin infill thickness varies from ~200–300 m in the north to more than 450 m to the southeast. Our subsurface model indicates a strong structural control on the architecture of the basin and highlights that the MAV experienced considerable modifications in its configuration over time. The buried shape of the MAV suggests a recent and still ongoing predominant tectonic control by the NW‐SE trending Paganica‐San Demetrio Fault System (PSDFS), which crosscuts older ~ENE and NNE trending extensional faults. Furthermore, we postulate that the present‐day arrangement of the PSDFS is the result of the linkage of two previously isolated fault segments. We provide constraints on the location of the southeastern boundary of the PSDFS, defining an overall ~19 km long fault system characterized by a considerable seismogenetic potential and a maximum expected magnitude larger than M 6.5. This study emphasizes the benefit of combining two easily deployable geophysical methods for reconstructing the 3‐D geometry of a tectonically controlled basin. Our joint approach provided us with a consistent match between these two independent estimations of the basin substratum depth within 15%.

A series of investigations has been carried out over the last decade in Europe aimed at deriving quantitative information on site amplification from non-invasive techniques, based principally on surface wave interpretations of ambient noise measurements. The present paper focuses on their key outcomes regarding three main topics. First, methodological, hardware and software developments focusing on the acquisition and the processing of both single point and array microtremor measurements, led to an efficient tool with in situ control and processing, giving rise to robust and reproducible results. A special attention has been devoted to the derivation and use of the Rayleigh wave ellipticity. Second, the reliability of these new tools has been assessed through a thorough comparison with borehole measurements for a representative – though limited – set of sites located in Southern Europe, spanning from stiff to soft, and shallow to thick. Finally, correlations between the site parameters available from such non-invasive techniques, and the actual site amplification factors as measured with standard techniques, are derived from a comprehensive analysis of the Japanese KIKNET data. This allows to propose alternative, simple site characterization providing an improved variance reduction compared with the “classical” VS30 classification. While these results could pave the road for the next generation of building codes, they can also be used now for regulatory site classification and microzonation studies, in view of improved mapping and estimation of site amplification factors, and for the characterization of existing strong motion sites