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Research is carried out in the Public Research Institutes and Research needs flexibility and organisational specificity with respect to a prevalently administrative Public Administration. This article represented the possible critical issues of a rough application of Smart Working in Public Research Institutions. We showed how the Researchers and Technologists already carry out research activities independently and that their results are peer-reviewed according to Research Quality Evaluation by the National Agency for the Evaluation of Universities (ANVUR). We focused on pointing out that the evaluation of smart working research activity by the administrative manager does not appear to be correct and that this cannot be the subject of the performance monitoring and evaluation system. We cited the regulations that state how research activities and management activities are separate and that the latter are in support of research. Articles of the National Collective Labour Agreement (CCNL) for the Researchers and Technologists section were cited that already make their work "smart" and "agile." In a survey to 585 INGV Researchers and Technologists, we asked them whether smart working could be the right tool for Research. The 372 responses (64 percent) to the survey, represented in the article, show strong cohesion in claiming the principles of autonomy and freedom of research even challenging some stances of recent years by INGV administrative leadership. Researchers and Technologists want to be part of the decision-making processes that affect them so as not to feed a bureaucratic apparatus that takes away time and energy. The demand that emerges from this survey is the proper application of the National Collective Labour Agreement for Researchers and Technologists, Smart Working, smart working organisational plan and individual agreements for smart working in Public Research Institutes in accordance with the rights of Researchers and Technologists in a working environment where the administration is truly supportive and facilitative of research.

The Neapolitan volcanic area is by far the highest volcanic risk one in the World, due to the presence of three active volcanic areas (Vesuvius, Campi Flegrei, Ischia) with an extreme population density: three millions people live within 20 km from a possible volcanic vent. Volcanic risk in these areas is strictly associated to seismic risk, and to other secondary risks as landslides and flooding.The mitigation of such an extreme risk can only be afforded by considering volcanological, as well as economical, urbanistic and social issues. All these highly multidisciplinary aspects must be jointly recognized and shared by both volcanologists and decision makers, in a global, effective risk reduction policy.We start considering the very high number of people living in the ‘red zones’ (the most risky areas, in terms of the actual emergency plans) of Vesuvius and Campi Flegrei, and the economic losses linked to a complete evacuation of these areas. We then demonstrate, from volcanological considerations, that evacuated people could not come back in the red zones in short times, but rather after years or decades, perhaps never again.From such basic considerations, we proceed to propose a multidisciplinary, effective mitigation strategy and emergency planning, which can significantly decrease the volcanic and associated risks in the area and to make effectively feasible and sustainable an evacuation, in case of high probability for an impending eruption. The proposed strategy also uses the most advanced Artificial Intelligence methodologies to plan an optimal, complete relocation of the population living in the most risky areas, in case of sudden as well as progressive evacuation. In addition, our mitigation strategy takes into account other key demographic and economic issues: problems affecting several internal areas of Southern Italy, which can help to handle the problem of risk mitigation, and to possibly jointly solve them.

We present a new stratigraphy, inferred from several drillings carried out in the framework of the ICDP Campi Flegrei Deep Drilling Project , for the largest volcanic eruption in Europe since at least the Late Pleistocene. The eruption produced the Campanian Ignimbrite of southern Italy. It is conventionally believed to have triggered collapse of the large Campi Flegrei caldera, which, in turn, has been identified as a source for future ignimbrite volcanism. New borehole and radioisotopic data challenge this interpretation. They indicate that the Campanian Ignimbrite was erupted through fissures in the Campanian Plain, north of Campi Flegrei, and was not responsible for caldera collapse. The results are consistent with ignimbrite volcanism being controlled by a common magmatic system beneath the Campanian Plain. Understanding the dynamics of the whole plain is thus essential for evaluating the likelihood of similar future events.

In the past 5 years, hydrothermal activity in the Pisciarelli fumarolic field of the Campi Flegrei caldera (southern Italy) has increased dangerously. This has led local and civil protection authorities to restrict access to volcanological monitoring in the area. We present a sampling system designed for real-time atmospheric measurements of hydrothermal gasses using an unmanned aircraft system (UAS) to investigate the Pisciarelli fumarolic field. UAS use has become an increasingly essential tool for monitoring areas where access is risky for operators. We also describe a low-cost gas sensor array that is designed and fabricated to be assembled and mounted on a commercial drone. The system is equipped to measure methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and sulfur dioxide (H2S) and is capable of displaying real-time gas concentration values. Our research explores the capabilities of this system and provides some encouraging results to be implemented in future sampling campaigns for gasses emitted into the atmosphere.

The continuous evolution of the SARS-CoV-2 virus genome and the consequent substitutions observed in the amino acid sequences, can induce significant changes in parameters such as diffusivity and pathogenicity, and causes constant concern regarding the efficacy of vaccines against the new variants in circulation. In recent months there has been an increase in the number of infections first in India, and more recently in the United Kingdom. The genome sequencing of the samples showed that this increase coincided with the emergence of a new variant, B.1.617.2, also known as VOC Delta. This variant is rapidly becoming dominant in several countries, causing increasing concern for its extreme diffusivity and its ability to often overcome the vaccines. The high diffusivity of this variant is normally ascribed to the Spike protein mutations. However, we will show here that it is rather due to the nucleocapsid substitution N:G215C. This is made clear by comparing, in the genomic sequences available on the GISAID database, the relative increase of the Delta variant with and without the associated N:G215C substitution. Once the extreme diffusivity of the Delta variant with associated nucleocapsid aminoacidic substitution is evidenced, we tentatively explain it as possibly due to the adaptive effect of the highly selective environment in Countries with high levels of vaccination.

Unconventional geothermal resource development can contribute to increase power generation from renewable energy sources in countries without conventional hydrothermal reservoirs, which are usually associated with magmatic activity and extensional faulting, as well as to expand the generation in those regions where conventional resources are already used. Three recent drilling experiences focused on the characterization of unconventional resources are described and compared: the Campi Flegrei Deep Drilling Project (CFDDP) in Italy, the United Downs Deep Geothermal Power (UDDGP) project in the United Kingdom, and the DEEP Earth Energy Production in Canada. The main aspects of each project are described (geology, drilling, data collection, communication strategies) and compared to discuss challenges encountered at the tree sites considered, including a scientific drilling project (CFDDP) and two industrial ones (UDDGP and DEEP). The first project, at the first stage of pilot hole, although not reaching deep supercritical targets, showed extremely high, very rare thermal gradients even at shallow depths. Although each project has its own history, as well as social and economic context, the lessons learned at each drilling site can be used to further facilitate geothermal energy development., This research was co-funded by ICDP consortium and INGV for the CFDDP. Grant number CFDDP 05-2008.

The health emergency due to Covid-19 has projected the employees of the Italian public administration into targeted and, essentially, forced smart working for everyone. This, together with the immediate benefit of mitigating the effects of the pandemic, has brought out the advantages and disadvantages of its application to the world of Research. Through an analysis of the differences between technical-administrative services and research activities, and taking as a reference the National Collective Labor Agreement, we want to highlight, in this article, the unresolved issues of the full application of smart working also in view of the application a smart working organizational plan that the Public Research Institutes administrations must prepare annually. The aim of this article is to emphasize the specificities of the Research with respect to administrative management with a view to constructive collaboration and to improve the functioning of the Institution.A survey of 585 Researchers and Technologists of a large Italian research institute, the National Institute of Geophysics and Volcanology, clearly showed the positions of the employees on the key points of the question of the application of smart working, that respects the dictates of the National Collective Agreement of Researchers and Technologists regarding the autonomy and freedom of research enshrined in our legal system based on the Constitutional Charter. The analysis of the results may promote the identification of possible harmonization between smart working and research activity to find the model that meets one's needs and characteristics that can be shared by the entire scientific community of Italian Public Research Institutes and both advantage of working well-being even in health emergencies.

The coronavirus (COVID-19) pandemic was particularly invasive in Italy during the period between March and late April 2020, then decreased in both the number of infections and in the seriousness of the illness throughout the summer of 2020. In this work, we measure the severity of the disease by the ratio of Intensive Care Units (ICU) spaces occupied by COVID-19 patients and the number of Active Cases (AC) each month from April to October 2020. We also use the ratio of the number of Deaths (D) to the number of Active Cases. What clearly emerges, from rigorous statistical analysis, is a progressive decrease in both ratios until August, indicating progressive mitigation of the disease. This is particularly evident when comparing March&ndash, April with July&ndash, August, during the summer period the two ratios became roughly 18 times lower. We test such sharp decreases against possible bias in counting active cases and we confirm their statistical significance. We then interpret such evidence in terms of the well-known seasonality of the human immune system and the virus-inactivating effect of stronger UV rays in the summer. Both ratios, however, increased again in October, as ICU/AC began to increase in September 2020. These ratios and the exponential growth of infections in October indicate that the virus&mdash, if not contained by strict measures&mdash, will lead to unsustainable challenges for the Italian health system in the winter of 2020&ndash, 2021.

The coronavirus (COVID-19) pandemic was particularly invasive in Italy during the period between March and late April 2020 then decreased in both in the number of infections and in the seriousness of the illness throughout the summer of 2020. In this discussion, we measure the severity of the disease by the ratio of Intensive Care Units (ICU) spaces occupied by COVID-19 patients and the number of Active Cases (AC) each month from April to October 2020. We also use the ratio of the number of Deaths (D) to the number of Active Cases. What clearly emerges, from rigorous statistical analysis, is a progressive decrease in both ratios until August, indicating progressive mitigation of the disease. This is particularly evident when comparing March-April with July-August; during the summer period the two ratios became roughly 18 times lower. We test such sharp decreases against possible bias in counting active cases and we confirm their statistical significance. We then interpret such evidence in terms of the well-known seasonality of the human immune system and the virus-inactivating effect of stronger UV rays in the summer. Both ratios, however, increased again in October as ICU/AC began to increase in September 2020. These ratios and the exponential growth of infections in October indicate that the virus - if not contained by strict measures - will lead to unsustainable challenges for the Italian health system in the winter of 2020-2021.

We statistically investigate the Coronavirus Disease 19 (COVID-19) pandemic, which became particularly invasive in Italy in March 2020. We show that the high apparent lethality or case fatality ratio (CFR) observed in Italy, as compared with other countries, is likely biased by a strong underestimation of the number of infection cases. To give a more realistic estimate of the lethality of COVID-19, we use the actual (March 2020) estimates of the infection fatality ratio (IFR) of the pandemic based on the minimum observed CFR and analyze data obtained from the Diamond Princess cruise ship, a good representation of a &ldquo, laboratory&rdquo, case-study from an isolated system in which all the people have been tested. From such analyses, we derive more realistic estimates of the real extent of the infection as well as more accurate indicators of how fast the infection propagates. We then isolate the dominant factors causing the abnormal severity of the disease in Italy. Finally, we use the death count&mdash, the only data estimated to be reliable enough&mdash, to predict the total number of people infected and the interval of time when the infection in Italy could end.

Recent calamities in Italy caused by natural disasters encouraged scientists and politicians to assess the need to find instruments for limiting risks. Risk Management suggests methods of adopting various options. A successful approach, thanks to the inexorable growth of digital technology, involves the use of the information infers from the decoding of Big Data. The radical technological advances generated by digital technologies require the application of appropriate statistical tools. The adoption of more flexible and interactive tools and strategies to analyses the natural phenomena (e.g. floods and landslides) as well as possible disasters like eruptions and earthquakes could ensure an optimal response to risk transfer and management.

L'area Napoletana è di gran lunga quella con rischio vulcanico maggiore al Mondo, per la presenza di tre aree vulcaniche attive (Vesuvio, Campi Flegrei, Ischia) con un'estrema densità di popolazione: tre milioni di persone vivono entro una distanza di circa 20 km da una possibile bocca vulcanica. Il rischio vulcanico in queste aree è strettamente associato al rischio sismico e ad altri rischi secondari, come frane e inondazioni. La gestione di un rischio così estremo può essere garantita solo considerando congiuntamente tutti gli aspetti del problema: vulcanologici, economici, urbanistici, psicologici e sociali. Tutti questi aspetti, altamente multidisciplinari, devono essere riconosciuti e condivisi sia dagli esperti delle varie discipline che dai decisori, in una politica globale ed efficace di riduzione del rischio.

Large earthquakes occurring worldwide have long been recognized to be non Poisson distributed, so involving some large scale correlation mechanism, which could be internal or external to the Earth. Till now, no statistically significant correlation of the global seismicity with one of the possible mechanisms has been demonstrated yet. In this paper, we analyze 20 years of proton density and velocity data, as recorded by the SOHO satellite, and the worldwide seismicity in the corresponding period, as reported by the ISC-GEM catalogue. We found clear correlation between proton density and the occurrence of large earthquakes (M > 5.6), with a time shift of one day. The significance of such correlation is very high, with probability to be wrong lower than 10–5. The correlation increases with the magnitude threshold of the seismic catalogue. A tentative model explaining such a correlation is also proposed, in terms of the reverse piezoelectric effect induced by the applied electric field related to the proton density. This result opens new perspectives in seismological interpretations, as well as in earthquake forecast.

The Campanian Ignimbrite (CI) is composed of two 39 ka depositional units, clearly distinguished by their areal distribution and welding characteristics. CI unit-1 is at the base and is covered in some areas by CI unit-2. CI unit-1 is a lower aspect ratio (V/H = 2 × 10−4) than CI unit-2. CI unit-1 covers an area of about 12,000 km2, has an average deposit thickness of 30 m, with a total volume of 250–300 km3, and is totally buried in the Campanian Plain defined herein as the Campanian volcanic zone (CVZ). Several drillings have been carried out within western Giugliano area, where from drilling stratigraphy the CI unit-1 appears as unwelded coherent to densely welded gray tuff. These degrees of welding intensity, shown by a large range of uniaxial compressive strength (UCS, σc) values (σc 1–60 N/mm2), are interpreted to be a result of different lithostatic loads. In distal areas, the CI unit-1 is composed of unwelded tuff (this has a local name of Cinerazzo) and unwelded coherent to incipiently welded tuff (this has a local name of pipernoid tuff), with a USCS range of σc 1–4 N/mm2. In the north, east, and southeast part of the Northern-CVZ, the CI-dense pyroclastic currents flowed: (a) on the flat plain until the southern slope of Roccamonfina volcano and (b) in the Apennine transversal valleys or partly stopped by Apennine relief. These structures, acting as barriers, exerted a dynamic pressure at the base of the flow, with relative temperature increase, able to modify, even in the distal areas, the welding intensity, reaching the stage of Piperno, that is partially welded with fiamme (σc 9–30 N/mm2). A common denominator of currents depositing the CI unit-1 and overtopping the high ridges of the Apennine chain is both the reversal of flow direction downstream of the obstruction and the formation of portions of the current that spill over the barrier, less dense than the bulk current from which a basal layer originates.

The goal of fluid geochemistry of fumarolic systems is to constrain the thermodynamic response of a multiphase (at least two-phase) and multicomponent hydrothermal fluid system, which has enough degrees of freedom to respond to variations of external constraints, such as magmatic gas injections, by reequilibrating phase proportions and compositions of dissolved gas components. For active volcanic systems, such as Campi Flegrei caldera (CFc), this puts first-order constraints on the nature of the source that geophysical inversion of geodetic and gravimetric data can neither identify nor resolve. In this study, based on the geochemical record at CFc in the last 35 years, we review two main approaches appearing in the literature, yielding diametrically opposite conclusions for the 1982–84 and ongoing (post-2000) CFc unrest episodes. We show that inert gases help evaluate the geochemical signature of deep ascending gas, not compatible with magma migration at shallow depths during episodes of unrest. After exhaustion of the volatile content of the shallow magma emplaced in 1982–84, only the deep-sourced (8 km) magmatic gas (actually a supercritical fluid) feeds and warms up the present-day hydrothermal system. In addition, shallow steam condensation occurs certainly in the surroundings of fumarole emissions, but it was attained at fumaroles in few circumstances during the 1982–84 unrest. We establish that the nature of the 1982–84 unrest was magmatic due to the emplacement of a shallow (3–4 km deep) magma. This interfered with the “normal” degassing dynamics from the deep (8 km) magmatic reservoir of regional size. On the contrary, the post-2005 unrest is unlikely magmatic and likely hydrothermal. The pictured scenarios confirm in all cases, and independently of the type of unrest, the strong role played by the CO2-rich gas release of deep provenance.

The important scientific questions that will form the basis of a full proposal to drill a deep well to the ductile–brittle transition zone (T>400 ∘C) at Newberry Volcano, central Oregon state, USA, were discussed during an International Continental Drilling Program (ICDP) sponsored workshop held at the Oregon State University-Cascades campus in Bend, Oregon, from 10 to 13 September 2017. Newberry Volcano is one of the largest geothermal heat reservoirs in the USA and has been extensively studied for the last 40 years. The Newberry Deep Drilling Project (NDDP) will be located at an idle geothermal exploration well, NWG 46-16, drilled in 2008, 3500 m deep and 340–374 ∘C at bottom, which will be deepened another 1000 to 1300 m to reach 500 ∘C. The workshop concluded by setting ambitious goals for the NDDP: (1) test the enhanced geothermal system (EGS) above the critical point of water, (2) collect samples of rocks within the brittle–ductile transition, (3) investigate volcanic hazards, (4) study magmatic geomechanics, (5) calibrate geophysical imaging techniques, and (6) test technology for drilling, well completion, and geophysical monitoring in a very high-temperature environment. Based on these recommendations, a full drilling proposal was submitted in January 2018 to the ICDP for deepening an existing well. The next steps will be to continue building a team with project, technology, and investment partners to make the NDDP a reality.

The coastline of the Gulf of Naples, Italy, is characterized by a series of infrastructures of strategic importance, including touristic and commercial ports between Pozzuoli to Sorrento, main roads, railways, and urban areas. Furthermore, the Gulf of Naples hosts an intense traffic of touristic and commercial maritime routes. The risk associated with extreme marine events is hence very significant over this marine and coastal area. On 28 December 2020, the Gulf of Naples was hit by an extreme sea storm, with severe consequences. This study focuses on the waterfront area of Via Partenope, where the waves overrun the roadway, causing massive damage on coastal seawall, road edges, and touristic structures (primarily restaurants). Based on the analysis of the meteorological evolution of the sea storm and its effects on the waterfront, we suggest that reflective processes induced on the sea waves by the tuff cliffs at the base of Castel dell’Ovo had an impact in enhancing the local-scale waves magnitude. This caused in turn severe flooding of the roadway and produced widespread damage along the coast. The analysis of the event of 28 December 2020, also suggests the need of an effective mitigation policy in the management of coastal issues induced by extreme sea storm events. Wind-based analysis and prediction of the sea wave conditions are currently discussed in the literature; however, critical information on wave height is often missing or not sufficient for reliable forecasting. In order to improve our ability to forecast the effects of sea storm events on the coastline, it is necessary to analyze all the components of the coastal wave system, including wave diffraction and reflection phenomena and the tidal change. Our results suggest in fact that only an integrated approach to the analysis of all the physical and anthropic components of coastal system may provide a correct base of information for the stakeholders to address coastal zone planning and protection.

This study investigates fumarolic CO2 emissions at Campi Flegrei (Southern Italy) and their dispersion in the lowest atmospheric boundary layer. We innovatively utilize a Lagrangian Stochastic dispersion model (WindTrax) combined with an Eulerian model (DISGAS) to diagnose the dispersion of diluted gas plumes over large and complex topographic domains. New measurements of CO2 concentrations acquired in February and October 2014 in the area of Pisciarelli and Solfatara, the two major fumarolic fields of Campi Flegrei caldera, and simultaneous measurements of meteorological parameters are used to: 1) test the ability of WindTrax to calculate the fumarolic CO2 flux from the investigated sources, and 2) perform predictive numerical simulations to resolve the mutual interference between the CO2 emissions of the two adjacent areas. This novel approach allows us to a) better quantify the CO2 emission of the fumarolic source, b) discriminate “true” CO2 contributions for each source, and c) understand the potential impact of the composite CO2 plume (Pisciarelli “plus” Solfatara) on the highly populated areas inside the Campi Flegrei caldera.

We applied the Eulerian code DISGAS (DISpersion of GAS) to investigate the dispersion of the hydrogen sulfide (H 2 S) from 32 geothermal power plants (out of 35 active) belonging to the geothermal districts of Larderello, Travale-Radicondoli and Monte Amiata, in Tuscany (Italy). An updated geographic database, for use in a GIS environment, was realized in order to process input data required by the code and to handle the outputs. The results suggest that H 2 S plumes emitted from geothermal power plants are mainly concentrated around the stacks of emission (H 2 S concentration up to 1100 μg/m 3 ) and rapidly dilute along the dominant local wind direction. Although estimated values of air H 2 S concentrations are orders of magnitude higher than in unpolluted areas, they do not indicate an immediate health risk for nearby communities, under the more frequent local atmospheric conditions. Starting from the estimated values, validated by measurements in the field, we make some considerations about the environmental impact of the H 2 S emission in all the geothermal areas of the Tuscany region.

Volcanic unrest at calderas involve complex interaction between magma, hydrothermal fluids and crustal stress and strain. Campi Flegrei caldera (CFc), located in the Naples (Italy) area and characterised by the highest volcanic risk on Earth for the extreme urbanisation, undergoes unrest phenomena involving several meters of uplift and intense shallow micro-seismicity since several decades. Despite unrest episodes display in the last decade only moderate ground deformation and seismicity, current interpretations of geochemical data point to a highly pressurized hydrothermal system. We show that at CFc, the usual assumption of vapour-liquid coexistence in the fumarole plumes leads to largely overestimated hydrothermal pressures and, accordingly, interpretations of elevated unrest. By relaxing unconstrained geochemical assumptions, we infer an alternative model yielding better agreement between geophysical and geochemical observations. The model reconciles discrepancies between what observed 1) for two decades since the 1982-84 large unrest, when shallow magma was supplying heat and fluids to the hydrothermal system, and 2) in the last decade. Compared to the 1980's unrest, the post-2005 phenomena are characterized by much lower aquifers overpressure and magmatic involvement, as indicated by geophysical data and despite large changes in geochemical indicators. Our interpretation points out a model in which shallow sills, intruded during 1969-1984, have completely cooled, so that fumarole emissions are affected now by deeper, CO2-richer, magmatic gases producing the modest heating and overpressure of the hydrothermal system. Our results have important implications on the short-term eruption hazard assessment and on the best strategies for monitoring and interpreting geochemical data. This article is protected by copyright. All rights reserved.

Monitoring volcanic phenomena is a key question, for both volcanological research and for civil protection purposes. This is particularly true in densely populated volcanic areas, like the Campi Flegrei caldera, which includes part of the large city of Naples (Italy). Borehole monitoring of volcanoes is the most promising way to improve classical methods of surface monitoring, although not commonly applied yet. Fiber optics technology is the most practical and suitable way to operate in such high temperature and aggressive environmental conditions. In this paper, we describe a fiber optics Distributed Temperature Sensing (DTS) sensor, which has been designed to continuously measure temperature all along a 500 m. deep well drilled in the west side of Naples (Bagnoli area), lying in the Campi Flegrei volcanic area. It has then been installed as part of the international &lsquo, Campi Flegrei Deep Drilling Project&rsquo, and is continuously operating, giving insight on the time variation of temperature along the whole borehole depth. Such continuous monitoring of temperature can in turn indicate volcanic processes linked to magma dynamics and/or to changes in the hydrothermal system. The developed monitoring system, working at bottom temperatures higher than 100 &deg, C, demonstrates the feasibility and effectiveness of using DTS for borehole volcanic monitoring.

The Campi Flegrei caldera in Southern Italy is one of the most populated active volcanoes on Earth. It has an unprecedented record of historical unrest and eruption that dates back to 2.2 ka BP and provides key insights for understanding the dynamic evolution of large calderas. Since 1950, it has undergone four episodes of caldera-wide uplift and seismicity, which have raised the coastal town of Pozzuoli, near the centre of unrest, up to 4.5 m and triggered the repeated evacuation of some 40,000 people. After about 20 years of subsidence, following the uplift peak reached in 1984, the caldera started a new, low rate uplift episode, accompanied by low magnitude seismicity and marked geochemical changes in fumaroles. In this area it is crucial to discriminate episodes of shallow magma intrusion from hydrothermal perturbations, which are both able to generate unrest signals. In this paper, by a critical review of previous literature and some new results, we discriminate, in the unrest episodes, the relative contributions of hydrothermal effects and shallow magma intrusions. Our review is aimed also to show the different behavior of the largest unrest episodes, such as the 1982–1984, and the present, ungoing unrest characterized by smaller rate but longer lasting uplift. We show that for the former, larger uplift of the 80's, there is clear evidence for shallow magma intrusion, and we are able to compute the amount of intruded magma volume. For the present, on-going uplift, on the contrary, there is no evidence for magmatic activity at shallow depth. As a main result of our analysis, we demonstrate here the present unrest, characterized by much lower uplift rates and seismicity, is only interpretable as due to large gas fluxes coming from the deeper magma reservoir; without any appreciable contribution from shallow magma or recent magmatic intrusion. Our results shed new light on the interpretation of caldera unrest worldwide, and clearly indicate the most constraining data and the most rigorous procedures of data analysis for a correct interpretation of volcanic unrest.

Ischia island, in the province of Naples, is a densely populated volcanic island, in which small to moderate magnitude earthquakes occur. Due to the very shallowdepth of such events (< 2 km), they can generate serious damage and casualties, up to the complete destruction of urban centers located within short epicentraldistance. Almost all of the earthquakes at Ischia island occur at shallow depth, beneath the Northern slopes of the Mt. Epomeo horst, which is located very close to thetown of Casamicciola. In fact, Casamicciola was completely destroyed by the 1883 earthquake (2313 victims) and experienced intensities up to XI degree on theMercalli scale. Historical records show that the background seismicity here is almost absent, but larger earthquakes tend to occur in clusters, lasting some decadesand with intervals between consecutive events on the order of years to decades. The clustering in time and the very shallow hypocentres, which cause, with respect totectonic earthquakes of similar magnitude, larger effects though limited to a relatively small area, make the seismicity in this island very peculiar. Despite suchdestructive record, till now official hazard maps strongly underestimated the seismic hazard in this area. On August 21st 2017, a very shallow earthquake with rathersmall magnitude struck the area of Casamicciola, killing two people, injuring many more and causing huge damage and partial to total collapse of edifices located justabove the earthquake fault.The maximum acceleration recorded for this earthquake exceeded by more than a factor of two the reference acceleration that should be sustained by edifices,according to official hazard maps. We propose here a complete procedure to assess and mitigate the risk, which can be rapid and economically affordable and, at thesame time, can avoid further grief due to possible occurrence of other destructive earthquakes within a short time interval. We describe the most likely buildingcollapse and casualty scenarios, in case that low-to-moderate magnitude earthquakes would occur before the edifices would be appropriately reinforced and secured.Our scenarios demonstrate the urgent need for securing operations. The proposed procedures for assessing seismic hazard and for securing urban areas provide anexample that is potentially applicable to the whole Italian peninsula. They may allow in fact the mitigation of the destructive impact of a large number of earth-quakes, which in Italy are often characterized by low or moderate magnitudes.

The 501 m deep hole of the Campi Flegrei Deep Drilling Project, located west of the Naples metropolitan area and inside the Campi Flegrei caldera, gives new insight to reconstruct the volcano-tectonic evolution of this highly populated volcano. It is one of the highest risk volcanic areas in the world, but its tectonic structure, eruptive history, and size of the largest eruptions are intensely debated in the literature. New stratigraphic and 40Ar/39Ar geochronological dating allow us to determine, for the first time, the age of intracaldera deposits belonging to the two highest magnitude caldera-forming eruptions (i.e., Campanian Ignimbrite, CI, 39 ka, and Neapolitan Yellow Tuff, NYT, 14.9 ka) and to estimate the amount of collapse. Tuffs from 439 m of depth yield the first 40Ar/39Ar age of ca. 39 ka within the caldera, consistent with the CI. Volcanic rocks from the NYT were, moreover, detected between 250 and 160 m. Our findings highlight: (i) a reduction of the area affected by caldera collapse, which appears to not include the city of Naples; (ii) a small volume of the infilling caldera deposits, particularly for the CI, and (iii) the need for reassessment of the collapse amounts and mechanisms related to larger eruptions. Our results also imply a revaluation of volcanic risk for the eastern caldera area, including the city of Naples. The results of this study point out that large calderas are characterized by complex collapse mechanisms and dynamics, whose understanding needs more robust constraints, which can be obtained from scientific drilling.

The active volcanic area of Campi Flegrei represents one of the “hottest” sites of worldwide continental areas. Exploitation for geothermal energy of this volcano is of great interest, because temperatures>150 °C occur at very shallow depth (0.5–1 km). Since present time, the exploitation of geothermal energy in Italy, for electric uses, has been confined to the Larderello and Mt. Amiata districts (Tuscany). With the recent introduction of new Italian regulations, which favor and incentivize innovative pilot power plants (5 MWe), many geothermal projects have been applied to volcanic districts of Southern Italy, providing a new important input to the development of zero-emission geothermal power plants. In this framework, we analyzed the sustainability of geothermal exploitation in the high temperature geothermal field of Mofete (Campi Flegrei caldera) in Southern Italy. By a review of all the available data of drillings performed at Mofete, from 1979 to 1987 by AGIP and ENEL companies, and using a numerical simulation (TOUGH2 ® ), we evaluate the thermal and pressure perturbation of the reservoirs, and the possible induced seismicity, due to extraction and reinjection of fluids, at different depths and temperatures. The results are fundamental in planning a sustainable geothermal energy production in urbanized and high volcanic risk areas.

The utility of new imaging technologies to better understand hazardous geological environments cannot be overstated. The combined use of unmanned aerial vehicles (UAV) and digital photogrammetry (DP) represents a rapidly evolving technique that permits geoscientists to obtain detailed spatial data. This can aid in rapid mapping and analyses of dynamic processes that are modifying contemporary landscapes, particularly through the creation of a time series of digital data to help monitor the geomorphological evolution of volcanic structures. Our study comprises a short-term (in geological terms) monitoring program of the dynamic and diffuse Pisciarelli degassing structure caused by the interplay between intensive rainfall and hydrothermal activity. This area, an unstable fumarole field located several hundred meters east of the Solfatara Crater of the Campi Flegrei caldera (southern Italy), is characterized by consistent soil degassing, fluid emission from ephemeral vents, and hot mud pools. This degassing activity is episodically accompanied by seismic swarms and macroscopic morphology changes such as the appearance of vigorously degassing vents, collapsing landslides, and bubbling mud. In late-2019 and 2020, we performed repeated photogrammetric UAV surveys using the Structure from Motion (SfM) technique. This approach allowed us to create dense 3D point clouds and digital orthophotos spanning one year of surveys. The results highlight the benefits of photogrammetry data using UAV for the accurate remote monitoring and mapping of active volcanoes and craters in harsh and dangerous environments.

Induced seismicity can be associated to the activity of fluid withdrawal and injection from/into the shallow crust (fracking, wastewater disposal into the deep crust, Enhanced Geothermal Systems technology, fluid extraction in oil fields and geothermal power plants). Long-term injection of large volumes of fluids is normally associated with induced seismicity, but the effect of withdrawal-reinjection in the same reservoir is less known, at least regarding its relation to simple injection. However, it is common experience worldwide that small (i.e. 10 MW or less) geothermal plants with withdrawal and re-injection of fluids in the same reservoir are mostly not associated with significant induced/triggered seismicity. This paper aims at understanding how to discriminate, on a numerical modelling basis, the seismogenic potential of withdrawal-reinjection with respect to injection only. With this aim, we analysed the induced pressure changes, the perturbed volumes of rocks and the potential for induced seismicity due to these operations. A set of simulations of injection or withdrawal-reinjection cycles, obtained by using the numerical code TOUGH2®, is applied to simple models of geothermal reservoirs, with varying permeability and lateral boundary constraints. For each permeability model, we then compare the time growth of perturbed volumes obtained with withdrawal-reinjection cycles to those obtained during simple injection, using the same flow rates. The size of perturbed volumes is then related to the maximum magnitude of induced/triggered seismicity, using models accredited in recent literature. Our results show that, for all models, withdrawal-reinjection is by far less critical than simple injection, because the perturbed volumes are remarkably smaller and remain constant over the simulated time, so minimizing the likelihood of interference with seismogenic faults. These results have significant implications for geothermal projects, and in the assessment of the potential risk related to fluid stimulation and induced seismicity.

In this study, we present the results of an analysis of Terrestrial Laser Scanning ( TLS) datasets, referred to multi-temporal (2013-2015) acquisition, aimed at evaluating volumetric changes and average retreat rates of the Coroglio tuff cliff, located in the western sector of Naples (Italy) in the Campi Flegrei caldera. The multi-temporal analysis was carried out in two steps: firstly, we developed a preliminary 3D Cloud-to-Cloud comparative analysis of point clouds obtained by TLS data processing, providing a view on geomorphological evolution; secondly, we obtained quantitative information by analyzing in GIS processing the differences between multi-temporal Digital Elevation Models. Finally, a morphometric analysis was carried out in order to evaluate retreat both retreat and failure rates. Four types of landslides (rock fall, debris fall, earth flow, and soil slip) have been accurately mapped in the different sectors of the cliff. The morphological analysis shows that several morphological variations have been recognized in different areas of the cliff with a maximum retreat of 8 m at the foot of the cliff due to the erosive action of the sea on poorly lithified deposits. We estimated that the average linear retreat rate related to the Coroglio cliff between 2013-2015, was equal to 0.07 m/yr; the linear retreat rate is higher (0.34 m/yr) at the base of the cliff, directly beaten by the sea waves. The results of the statistical analysis of the relationship between volume and area calculated for rock falls are consistent with the results of previous studies. Geo-structural analysis confirms that some discontinuity sets strongly control the failure kinematisms.

Deep drilling is a key tool for the investigation of active volcanoes in the modern Earth Sciences, as this provides the only means to obtain direct information on processes that occur at depth. Data acquired from drilling projects are fundamental to our understanding of volcano dynamics, and for mitigation of the hazards they pose for millions of people who live close to active volcanoes. We present here the first borehole measurement of the stress field in the crust of Campi Flegrei (southern Italy), a large active caldera, and one of the highest risk volcanoes worldwide. Measurements were performed to depths of ∼500 m during a pilot study for the Campi Flegrei Deep Drilling Project. These data indicate an extensional stress field, with a minimum horizontal stress of ca. 75% to 80% of the maximum horizontal stress, which is approximately equal to the vertical stress. The deviation from lithostatic conditions is consistent with a progressive increase in applied horizontal stress during episodes of unrest, since at least 1969. As the stress field is evolving with time, the outcome of renewed unrest cannot be assessed by analogy with previous episodes. Interpretations of future unrest must therefore accommodate the possibility that Campi Flegrei is approaching conditions that are more favourable to a volcanic eruption than has previously been the case. Such long-term accumulation of stress is not expected to be unique to Campi Flegrei, and so might provide a basis for improved forecasts of eruptions at large calderas elsewhere.