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Between August and November 2016, three major earthquake events occurred in Central Italy. The first event, with M6.1, took place on 24 August 2016, the second (M5.9) on 26 October, and the third (M6.5) on 30 October 2016. As part of the Italy-US GEER team investigation, we recorded the amplitude and character of offset on the Mount Vettore Fault Zone (MVFZ) using traditional manual field recording and mapping techniques and advanced state-of-the-art geomatics methods of LIDAR and Structure From Motion.Extensive field surveys by INGV geologists and the GEER team were performed on the flanks of Mt Vettore after the 24 August and 30 October events, and a limited survey was done between the two October events by INGV. These surveys indicated normal offset on several strands of the MVFZ, along the upper flanks of Mount Vettore and on the Piano Grande basin floor. The primary trace of the fault had measurable offset up to 215 cm in the northern section of the fault (42.810N-42.818N), and lesser offsets in the southern and central portion of the fault (42.796N-42.810N). In tandem with the traditional field recording of offset, we collected TLS-LIDAR at several locations and flew approximately 5 km of the fault with unmanned aerial systems (UAS) to image the offsets. Lidar and Structure-from-Motion point cloud models were merged to construct a virtual topographic model of the fault. Comparison between the virtual offsets in the point cloud data and the field measurements at the same location found close agreement within 20% of the measured field values. The results indicate that LIDAR and UAS-based methods for collecting and analyzing topographic fault offsets are accurate and potentially greatly improve the magnitude of fault offset data sets from events with measurable surface rupture.

Between August and November 2016, three major earthquake events occurred in Central Italy. The first event, with M6.1, took place on 24 August 2016, the second (M5.9) on 26 October, and the third (M6.5) on 30 October 2016. As part of the Italy-US GEER team investigation, we recorded the amplitude and character of offset on the Mount Vettore Fault Zone (MVFZ) using traditional manual field recording and mapping techniques and advanced state-of-the-art geomatics methods of LIDAR and Structure From Motion.Extensive field surveys by INGV geologists and the GEER team were performed on the flanks of Mt Vettore after the 24 August and 30 October events, and a limited survey was done between the two October events by INGV. These surveys indicated normal offset on several strands of the MVFZ, along the upper flanks of Mount Vettore and on the Piano Grande basin floor. The primary trace of the fault had measurable offset up to 215 cm in the northern section of the fault (42.810N-42.818N), and lesser offsets in the southern and central portion of the fault (42.796N-42.810N). In tandem with the traditional field recording of offset, we collected TLS-LIDAR at several locations and flew approximately 5 km of the fault with unmanned aerial systems (UAS) to image the offsets. Lidar and Structure-from-Motion point cloud models were merged to construct a virtual topographic model of the fault. Comparison between the virtual offsets in the point cloud data and the field measurements at the same location found close agreement within 20% of the measured field values. The results indicate that LIDAR and UAS-based methods for collecting and analyzing topographic fault offsets are accurate and potentially greatly improve the magnitude of fault offset data sets from events with measurable surface rupture.

The ancient city of Pompeii, destroyed by the 79 CE Plinian eruption of Vesuvius, is one of the most famous archaeological sites worldwide and an open-air laboratory for many disciplines. The destruction of Pompeii has so far been reconstructed in terms of a succession of volcanic phenomena and related effects, identified as the accumulation of pumice lapilli on roofs and dynamic pressure exerted by pyroclastic currents on buildings, and neglecting the potential effects of the syn-eruptive seismicity, the occurrence of which is beautifully described by an erudite eyewitness to the catastrophe, Pliny the Younger. During a recent excavation in the Insula dei Casti Amanti, in the central part of Pompeii, the peculiar evidence of building collapses, that overwhelmed two individuals, has been uncovered. The multidisciplinary investigation, involving archaeology, volcanology, and anthropology, gathered information on the construction technique of the masonry structures, the volcanological stratigraphy, the traumatic pattern of bone fractures of the skeletons, along with the detection of the wall displacements, that led to archaeoseismological considerations. The merging of the data has highlighted the need of an updated perspective in the assessment of the damage at Pompeii during the 79 CE eruption, by considering the syn-eruptive seismicity as a factor contributing to the destruction of the city and death of the inhabitants. By comparing the attitude and characteristics of different types of damage, and after ruling out any other possible damaging event, our conclusions point to the occurrence of syn-eruptive earthquake-induced failures of masonry structures. The structural collapses, based on our stratigraphic and volcanological data, are chronologically consistent with the beginning of the caldera-forming phase of the eruption which was accompanied by strong seismic shocks. The crush injuries of the skeletons of the two individuals are consistent with severe compression traumas and analogous to those shown by individuals involved in modern earthquakes testifying that, apart from other volcanic phenomena, the effects of syn-eruptive seismicity may be relevant. These outcomes lay the foundation for a more extensive study concerning the assessment of the contribution of the syn-eruptive seismic destruction at Pompeii and open new perspectives for volcanological, archaeoseismological and paleopathological studies. [ABSTRACT FROM AUTHOR]

De Giorgi's scientific activity in Abruzzi is mainly related to the geological surveys in the second half of the 1870s and to the involvement in the discussion about seismology in 1887, during the First Geodynamic Congress held in L'Aquila. Two scientific contributions on Bollettino del Regio Comitato Geologico d'Italia, published in 1877 and 1878 respectively, summarize the activity of 1870s. The former is related to geological investigations in the Pescara and Aterno river valleys, while the latter is the report of surveys in the area of Campo Imperatore (Gran Sasso chain) for the identification of lignite seams and bituminous schists potentially exploitable for industrial purposes. The work De Giorgi made at L'Aquila in 1887 is summarized in the text of the closing conference at the Geodynamic Congress, which gave him the opportunity to address arguments of overriding importance for Seismology at that time. Some of the points in De Giorgi's discussion are still relevant today, as the earthquake prediction and the defense against the seismic damage by using appropriate building techniques. In the whole, summaries of the performed activities, considerations and conclusions reported in the publications give us the image of De Giorgi as a cutting-edge researcher, a leading representative of Earth Sciences in the second half of the 19th century, for both the methodological approach and the deep knowledge of the theories governing geology and seismology at that time. [ABSTRACT FROM AUTHOR]

An active fault is defined capable (FAC) when, in fact, it is capable of offsetting the ground surface; while a seismogenic source (SS) is a tectonic structure that generates earthquakes and, under certain conditions, displaces the ground when the deep coseismic rupture propagates up to the surface. Therefore, the FACs may be considered as the surficial expression of SSs. The seismic sequences of central Italy in 2009 and 2016-2017 showed the importance to define and locate "in advance" FACs and SSs in any given area. However, the analysis of the scientific literature shows that the conceptual difference between the FAC and the SS is still marked in Italy. This is demonstrated by the availability of two distinct national databases, that deal separately with the FACs (ITHACA) and the SSs (DISS). This article analyses ITHACA and DISS in the 2009 and 2016-2017 seismic sequences epicentral areas and identifies possible conceptual differences and similarities between FAC and SS. It highlights the need of a welldefined methodological approach that can define and map a FAC as a surficial expression of a SS, to which a certain seismogenic and surface faulting potential can be associated. [ABSTRACT FROM AUTHOR]