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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.

We investigated the Late Quaternary activity of a major, crustal fault affecting the southern sector of Central Apennines, i.e., the Roveto Valley Fault (also known as Liri Valley fault). This sector of the chain was hit by numerous M>5 historical seismic events. For some of these, e.g., the 1654 one (Mw 6.33), the causative seismogenic source has never been conclusively defined. Within this seismotectonic framework, the recent activity of the Roveto Valley Fault is still a matter of debate. Some authors defined its activity as ended in the Middle Pleistocene; others considered it as currently active and seismogenic at least in its southern portion. We collected new geologic and geomorphologic data along the eastern (left) flank of the Roveto Valley, where the fault crops out, and we identified evidence of displacement of alluvial fans that we attributed to the Early, Middle, and Late Pleistocene. Moreover, the analysis of the relationship between colluvial/detrital deposits, chronologically constrained by means of radiocarbon dating, allowed us to define the activation of the Roveto Valley fault also during historical times, that is, over the past few centuries. Evidence of this has been collected along a large sector of the fault trace for a length of some tens of kilometres. The results of our studies contribute to improve the knowledge of the seismotectonic setting of a large sector of the Central Apennines. Indeed, proving the current activity of the Roveto Valley fault casts new light on possible seismogenic sources of major seismicity of central Italy, potentially responsible for severe damage over a wide area and to relevant cities, Rome being among them.

The entanglement between active tectonics and karst systems is well-known in the literature. Karst systems are sound recorders of continental deformation in terms of brittle structures and seismic features and have been successfully used as markers for reconstructing tectonic stresses and assessing preferential directions of increased permeability in oil and gas fields. Karst systems could also be exploited to evaluate the past activity of faults bounding karst hydrostructures, thus providing useful data for the assessment of the seismic hazard of a specific area. In this work, we look into the complex relationship among karst development, recent tectonics and groundwater flow, which appear to be strongly interconnected with each other, to assess the activity of faults bounding karst hydrostructures. We focused our attention on an active karst area located in the Mesozoic and Cenozoic carbonate reliefs of the Italian central Apennines. In this context, the morphological and morphometric features of the karst landforms (dolines, dry valleys, and cave entrances), identified with geomorphological surveys, and their mutual relationship with fractures and fault segments, identified employing geostructural analysis, document stasis and deepening events in karst evolution. Such events are related to changes in the groundwater table and the consequent variation of the paleokarst base level associated with the Quaternary fault activity. A comprehensive evaluation of the evolution of karst systems at local and regional scales, considering the hydrogeological influence on base levels, allows us to use karst landforms as a proxy to unravel fault activity and evolution in Italy and in other similar karst environments.

On 24th August 2016 a ML 6.0 earthquake occurred near Amatrice (central Italy) causing nearly 300 fatalities. The mainshock ruptured a NNW-SSE striking, WSW dipping normal fault. The earthquake produced several coseismic effects at ground, including landslides and ground ruptures. In particular, ground surveys identified a 5.2 km long continuous fracture along the Mt. Vettore flank, both on rock and slope deposits, along one of the active normal fault segments bounding the relief to the west. In this work, we evaluated the contribution of seismically-induced surface instabilities to the observed ground fractures by means of a permanent-displacement approach. The results of a parametric analysis show that the computed seismically-induced gravitational displacements (about 2-10 cm) are not enough to explain field observations, testifying to a mean 20-25cm vertical offset. Thus, the observed ground fractures are the result of primary faulting related to tectonics, combined with gravitational phenomena.

The August 24, 2016 Amatrice earthquake (Ml 6.0) struck a region of the central Apennines (Italy) where several active faults were known since decades, most of which are considered the surface expression of seismogenic sources potentially able to rupture during earthquakes with M of up to 6.5-7. The current debate on which structure/s activated during the mainshock and the possibility that conterminous faults may activate in a near future urged us gathering all the data on surface geological evidence of fault activity we collected over the past 15-20 years in the area. We then map the main tectonic structures of the 2016 earthquake epicentral and mesoseismal region. Our aim is to provide hints on their seismogenic potential, as possible contribution to the national Database of Individual Seismogenic Source (DISS) and to the Database of the active and capable fault ITaly HAzard from CApable faults (ITHACA).

Paleoseismological investigations have been carried out along the Mt. Marine normal fault, a probable source of the February 2, 1703 (Me=6.7) earthquake. The fault affects the area between the 2016 Amatrice and 2009 L’Aquila seismic sequences. Paleoseismological analysis provides data which corroborate previous studies, highlighting the occurrence of 5 events of surface faulting after the 6th–5th millenium B.C., the most recent of which is probably the 2 February 1703 earthquake. A minimum displacement per event of about 0.35 m has been measured. The occurrence of a minimum four faulting events within the last 7,000 years suggests a maximum 1,700 years recurrence interval.

On May 20, 2012, a Ml 5.9 seismic event hit the Emilia Po Plain, triggering intense earthquake activity along a broad area of the Po Plain across the provinces of Modena, Ferrara, Rovigo and Mantova (Figure 1). Nine days later, on May 29, 2012, a Ml 5.8 event occurred roughly 10 km to the SW of the first main shock. These events caused widespread damage and resulted in 26 victims. The aftershock area extended over more than 50 km and was elongated in the WNW-ESE direction, and it included five major aftershocks with 5.1 ≤Ml ≤5.3, and more than 2000 minor events (Figure 1). In general, the seismic sequence was confined to the upper 10 km of the crust. Minor seismicity with depths ranging from 10 km to 30 km extended towards the southern sector of the epicentral area (ISIDe, http://iside.rm.ingv.it/). […]