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Materiali per un catalogo dei terremoti italiani. Aggiornamento di studi speditivi
No full textThe latest version of the CPTI15 seismic catalogue (January 2022) includes more than two hundred earthquakes marked AMGNDT95. Their parameters are derived from expeditious studies produced as part of the GNDT/CNR ‘Hazard Project’ (1993-1995). Some of them simply parameterise data taken from bibliographic references in the PFG85 catalogue, i.e., mostly Mario Baratta’s seismological compilation “I terremoti d’Italia” [1901] or twentieth-century seismological bulletins. Others go back as far as the original sources of the references themselves.
As part of the B2 Convention between INGV and DPC (2016-2021), a review of these earthquakes was initiated, starting with the most relevant ones, for which a good margin of improvement in knowledge can be assumed. At the same time, first-level research was also begun on a dozen or so earthquakes of low energy, but still above the damage threshold, which for various reasons had never been studied so far and whose parameters in the CPTI15 are still those of the POS85 catalogue. We present here the results of the study of about thirty earthquakes belonging to both categories. The overall result is generally a strong improvement of the available information, from which it will be possible to derive epicentral parameters more up-to-date and more robust than the previous ones.Questo lavoro è stato realizzato nell’ambito della Convenzione fra INGV e Dipartimento nazionale della Protezione Civile, Allegato B2.Published1-2604T. Sismicità dell'ItaliaJCR Journa
Formal Matters on the Topic of Risk Mitigation: A Mathematical Perspective
No full textHow (in)formal should the classic expression describing risk as the product of hazard, exposure, and vulnerability be considered? What would be the most complete way to describe the process of risk mitigation? These are the questions we try to answer here, using a formal, mathematically sound yet abstract description of hazard, exposure, vulnerability, and risk. We highlight the elements that can be affected for the purpose of mitigation and show how this can improve the quantitative assessment of the procedural aspects of risk mitigation, both long- and short-term, down to the timescale of emergency response.Published265OSV4: Preparazione alle crisi vulcanicheJCR Journa
Understanding the drivers of volcano deformation through geodetic model verification and validation
No full textVolcano geodesy often involves the use of models to explain observed surface deformation. A variety of forward models are used, from analytical point sources to numerical simulations that consider complex magma system geometries, topography, and material properties. Various inversion methods can then be used to relate observed volcano data to models. Ideally, forward models should be verified through intercomparison, to check for implementation errors and quantify the error induced by any approximations used. Additionally, forward models and inversion methods should be validated through tests with synthetic and/or real data, to determine their ability to match data and estimate parameter values within uncertainty. However, to date, there have not been comprehensive verification and validation efforts in volcano geodesy. Here, we report on the first phase of the Drivers of Volcano Deformation (DVD) exercises, which were designed to build community involvement through web-based exercises involving calculations of static elastic displacement around pressurized magma reservoirs. The forward model exercises begin with a spherical reservoir in a homogeneous half space, then introduce topography, heterogeneous elastic properties, and spheroidal geometries. The inversion exercises provide synthetic noisy surface displacement data for a spherical reservoir in a homogeneous half space and assess consistency in estimates of reservoir location and volume/pressure change. There is variability in the results from both forward modeling and inversions, which highlights the strengths and limitations of different forward models, as well as the importance of inversion method choice and uncertainty quantification. This first phase of the DVD exercises serves as a community resource and will facilitate further efforts to develop standards of reproducibility.Published74OSV3: Sviluppo di nuovi sistemi osservazionali e di analisi ad alta sensibilitàJCR Journa
Big data and tourism research: measuring research impact
No full textDigital transformation and technological advances are causing a radical change in com‑
munication structures and in the way information is consumed. With rapid development of
computing and the Internet, data is generated, recorded, stored and accumulated on a large
scale, making it necessary for economic sectors to act quickly in order to adapt their busi‑
nesses to the online environment and thus, ensure their own survival. The application of
Big Data in tourism enables to transform all this data into useful information, so that com‑
panies in the sector can defne and optimize their strategies in order to increase their prof‑
its. This article performs a comparative bibliometric analysis of the presence and impact of
scientifc production related to Big Data within the area of tourism research indexed in the
WoS and Scopus databases. The aim is to know key aspects such as its growth, correlation,
citation, coverage, overlap, dispersion or concentration that will support future research‑
ers when they start their work in this emerging feld. From the analysis of the 113 articles
selected between the two bases through an advanced search for terms with a time limit set
in 2019, it can be concluded that this is a new feld of knowledge, which has aroused great
interest since 2017, publishing about two thirds of the articles during the period 2017–
2019. Although WoS and Scopus difer in general terms in scope and coverage policies,
both systems are complementary and not exclusive. In the specifc area of Big Data and
Tourism Research, Scopus is the base that provides better coverage by collecting a higher
number of articles and receiving more citations.Published271–292OSA5: Energia e georisorseN/A or not JC
Volcanism in Antarctica: An assessment of the present state of research and future directions
No full textOver the past decades, significant efforts have been made to understand the nature, dynamics and evolution of volcanic systems. In parallel, the continuous demographic expansion and extensive urbanization of volcanic areas have increased the exposure of our society to these natural phenomena. This increases the need to improve our capacities to accurately assess projected volcanic hazards and their potential socioeconomic and environmental impact, and Antarctica and the sub-Antarctic islands are no exception. More than a hundred volcanoes have been identified in Antarctica, some of which are entirely buried beneath the ice sheet and others as submarine volcanoes. Of these, at least eight large (basal diameters > c. 20-30 km) volcanoes are known to be active and pose a considerable threat to scientific and ever-increasing tourism activities being carried out in the region. Despite the scientific and socioeconomic interest, many aspects of the past volcanic activity and magmatic processes in Antarctica, and current volcanic hazards and risks, remain unknown. Moreover, many of Antarctica’s volcanoes preserve a remarkable history of the eruptive environment, from which multiple parameters of past configurations of the Antarctic ice sheet (AIS) can be deduced. Given the critical role that the AIS plays in regulating Earth’s climate, Antarctica’s volcanoes therefore can be regarded as the ground truth for current models of past climates derived from modelling and studies of marine sediments. Here, we provide a succinct overview of the evolution of volcanism and magmatism in Antarctica and the sub-Antarctic region over the past 200 million years. Then, we briefly review the current state of knowledge of the most crucial aspects regarding Antarctica’s volcanic and magmatic processes, and the contributions volcanic studies have made to our understanding of ice sheet history and evolution, geothermal heat flow, as well as present-day and future volcanic hazard and risk. A principal objective is to highlight the problems and critical limitations of the current state of knowledge and to provide suggestions for future potential directions of volcanic-driven investigations in Antarctica. Finally, we also discuss and assess the importance and scope of education and outreach activities specifically relating to Antarctic volcanism, and within the context of broader polar sciences.Published107941OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Deep fluids migration and submarine emersion of the Kalang Anyar mud volcano (Java, Indonesia): A multidisciplinary study
No full textNorth-east Java is part of a large sedimentary basin containing hydrocarbon provinces that feature diffuse hydrothermal systems, mud volcanoes, and degassing sites. Seismic profiles acquired to explore the basin reveal a broad distribution of palaeo- and modern piercement structures. The Watukosek fault system links the volcanic arc, to the south, with the Sidoarjo province, to the north. Several piercement structures, including the Kalang Anyar mud volcano, are hosted along this left-lateral strike-slip system that favors the migration of crustal fluids in this part of the basin. Here, we present a multidisciplinary geological, geophysical and geochemical study conducted at Kalang Anyar where dozens of seepage sites are active in the crater area and intermittently emit bursts oil, gas, mud, and water. The emitted gasses are methane-dominated with smaller amounts of heavier hydrocarbons and CO2. Unlike most mud volcanoes, at Kalang Anyar the mixed-thermogenic origin of the methane is coupled with geothermal anomalies, as indicated by helium and CO2 isotopic values (δ13CCO2 as high as −4‰) that suggest the input of mantle-derived gas. Our gas flux measurements reveal that Kalang Anyar emits about 1.62 and 5.75 t yr−1 of CO2 and CH4, respectively. The intense bubbling gives rise to a typical drumbeat seismic signal characterized by dominant frequencies around of 3–4 Hz (and up to 15 Hz). We interpret the drumbeat as fluids rising and resonating through shallow plumbing system of Kalang Anyar. Erupted clasts with different lithologies and shells are scattered across the mud volcano area, while the edges of the crater zone include cubic meter-sized carbonate-cemented blocks and ridges that contain siliciclastic sediments and abundant chemosymbiotic bivalves. Carbon isotope analyses of the carbonate cement (δ13C as low as −48.8‰) identify the latter as methanogenic chemoherms. Radiocarbon (14C) dating of bivalves cemented in the blocks indicates an age of 1890-1488 BP. These results indicate that the activity of Kalang Anyar MV dates from when the area was below sea level and that the microbially-mediated precipitation of carbonates was ongoing during subaqueous methane seepage at the crater site.
To the best of our knowledge, Kalang Anyar is the first example of a mud volcano that progressed from subaqueous to subaerial conditions during marine regression, displaying evidence of former marine activity (i.e. methanogenic carbonates) and current subaerial degassing at numerous seepage sites. Potentially eruptive phases represent a clear geohazard for the numerous settlements constructed inside the mud volcano. In light of this, it may be prudent to apply stricter rules for development activities, such as housing construction permits that consider the possibility of potentially catastrophic events, and apply steps to mitigate these hazards.Published1059706A. Geochimica per l'ambiente e geologia medicaJCR Journa
Quaternary uplift of palaeoshorelines in southwestern Crete: the combined effect of extensional and compressional faulting
No full textWe undertake spatio-temporal analysis on sequences of Pleistocene palaeoshorelines in southwestern Crete where deformed Holocene marine notches have predominantly been suggested to be linked to coseismic uplift from the 365 CE Mw > 8 earthquake. Previous investigations into the Holocene notches have been used to infer that the dominant mechanism of uplift may be slip either on a reverse crustal fault or on the subduction interface. However, seismic reflection studies attest to the presence of numerous active offshore extensional faults whose role in the long-term deformation is unclear. The relative contributions of upper-plate extensional and compressional faults to the overall deformation can be assessed through the study of uplifted and deformed Late Quaternary palaeoshorelines. New 36Cl exposure dating on wave-cut platforms and palaeoshoreline mapping are combined with existing age controls to facilitate investigation into the deformed Late Quaternary palaeoshorelines. We observe that the Late Quaternary uplift rates increase from west (0.61 mm/yr) to east (0.83 mm/yr) over ∼20 km, a spatial uplift pattern that is inconsistent with published vertical deformation models of slip solely on the subduction interface or on a reverse crustal fault. Elastic half-space modelling suggests that an offshore extensional fault may also contribute to the uplift. We conclude that a combination of active extensional and compressional faults may be responsible for Late Quaternary uplift across southwestern Crete.Published1082402T. Deformazione crostale attivaJCR Journa
Fault Rheology Control on Rupture Propagation and Aftershocks Distribution during the 2016–2017 Central Italy Earthquakes
No full textThe stress released by large coseismic ruptures and related aftershock sequences is a strongly
heterogeneous process. We show highly resolved images of the normal fault system ruptured during
the 2016-2017 Central Italy earthquake sequence, as obtained by high resolution local earthquake
tomography allowing relocation of a massive set of aftershocks. We get evidence that lateral changes
of elastic properties on the fault planes account for the complexity in the rupture processes during the
two M>6 earthquakes. We observe an emergent phase in the first part of the Mw6.5 rupture and the
coseismic slip becomes large when the rupture breaks through high Poisson ratio portions of the fault.
Mainshocks break fault portions that, although limited and segmented by inherited structural
complexity, were dynamically interfering during the faulting episodes. The close repetition of slip on
the same relatively high Poisson ratio patch suggests a dynamic weakening of the fault and/or an
incomplete stress release during the first mainshock.Published2642–2654OST3 Vicino alla fagliaJCR Journa
Hydrogeochemical and isotopic characterization of the Gioia Tauro coastal Plain (Calabria - southern Italy): A multidisciplinary approach for a focused management of vulnerable strategic systems
No full textThis work pursues the hydro-geochemical and isotopic characterization of the complex groundwater system of the Gioia Tauro Plain, one of the most important industrialized and agricultural coastal areas of southern Italy. The anthropic pressure exposes the water resources at risk of depletion and quality degradation making the plain groundwater a system of high scientific and social interest. The plain is characterized by a shallow aquifer, mostly recharged by local rains and a deep aquifer apparently less influenced by local precipitation. Both aquifers are mainly Ca-HCO3 waters except for localized sectors where Na-HCO3, Na-Cl and Ca-SO4 waters are present. In deep aquifer, both prolonged interaction with sedimentary rocks, mainly deriving from the erosion of crystalline rocks, and direct cation exchange represent the primary factors controlling the formation of Na-HCO3 waters. Mixing processes between these waters and either connate brine and/or deep thermal waters contribute to the formation of isolated high salinity Na-Cl-rich waters. In shallow aquifer, inputs of N-rich sewage and agriculture-related contaminants, and SOx emissions in proximity of the harbor are responsible of the increasing nitrate and sulphate concentrations, respectively. The Cl/Br and NO3/Cl ratios highlight contamination mainly linked to agricultural activities and contribution of wastewater. Along the northern boundary, the warmest groundwater (Na-Cl[SO4]) were found close to a bend of the main strike-slip fault system, locally favouring the rising of B- and Li-rich deep waters, testifying the influence of geological-structural features on deep water circulation. Despite the high-water demand, a direct marine intrusion is localized in a very restricted area, where we observed an incipient groundwater-seawater mixing (seawater contribution ≤7 %). The qualitative and quantitative conditions of the shallow aquifer still have acceptable levels because of the relatively high recharge inflow. A reliable hydrogeochemical conceptual model, able to explain the compositional variability of the studied waters, is proposed.Published1606946A. Geochimica per l'ambiente e geologia medicaJCR Journa
GNSS-RTT (GNSS - Real Time Tracker), a Software System For Real Time GNSS Data Acquisition, Processing And Visualization
No full textDuring any emergency response, the real-time GNSS data analysis strategies based on differential approach (i.e. Real Time Kinematic) needs some crucial a-priori information on the reference stations. In addition to their location in an undeformed area, this choice can be also influenced by other parameters (RMS of the time series, battery voltages, transmission on/off, number of visible satellites, etc.). For this reason, we developed an intelligent homemade algorithm BC-RTK (Base Choice - RTK) able to choose the more reliable baselines to potentially provide the best RTK results, it defines stations’ priority to the real-time GNSS analysis whose results are stored in a time-series database. This algorithm is a part of a software, called GNSS-RTT(Global Navigation Satellite System - Real Time Tracker), developed in 2022/2023. It is an open source software that can be either connected to different GNSS receivers through a different type of connection (Tcp/ip, Ntrip, etc.) or linked to a Ntrip Caster. For the solutions, it is able to get the data in different formats (NMEA, LLH,XYZ, etc.) and at different sampling frequencies up to 200 Hz. The data is stored in an optimized database called InfluxDB(https://www.influxdata.com) for real-time and IoT applications. It was developed to manage the data efficiently, allowing both real-time and post-processed visualization. The visualization is performed by means of web applications, such as Grafana (https://grafana.com) or Chronograf (https://www.influxdata.com/time-series-platform/chronograf). We will describe the technical aspects relating to the presented software and some preliminary results in test cases.Publishe