ALBERT

Description: In 2009, the German government launched its "National Development Plan for Electric Mobility" which set the concrete target of having 1 million electric vehicles on the road by 2020. However, there have been hypes around e-mobility before and even if this goal were to be reached, a merely quantitative aim of a certain number of electric vehicles will not suffice to contribute to a more sustainable development in transport. This requires a more comprehensive vision of sustainable e-mobility as a system innovation. Thus, the question addressed in this thesis is: How can we assess - at this critical early stage - whether there is potential for e-mobility developing as a sustainable system innovation? A theoretical framework will be developed for assessing the potential of a wider transition at an early stage by analyzing current patterns of socio-technical co-evolution and embedding these in a wider framework of the structural dynamics involved in transitions. The aim of the analysis is to identify whether 'system-innovative' projects do emerge in the case of Germany/Baden-Württemberg and what patterns (e.g. in terms of specific actor constellations, institutional adjustments etc.) can explain this. It will be shown that the system-innovative potential of this e-mobility niche remains limited, due to the powerful influence of incumbents, conflicting political goals and traditional science approaches. A few more system-innovative activities emerge where powerful actors from outside are involved, who are capable of viewing mobility in a more systemic way (e.g. actors from the public transport or housing sector). It is argued that the role of large demonstration projects is important, but they need to be designed as transdisciplinary research projects from the beginning.

Description: Many countries have started to develop policy programs for the sustainable use of natural resources. Indicators and targets can cover both a territorial and a life-cycle-wide global perspective. This article focuses on how a safe operating space for global material resource use can be outlined based on existing economy-wide material flow indicators. It reflects on issues such as scale and systems perspective, as the choice of indicators determines the target "valves" of the socio-industrial metabolism. It considers environmental pressures and social aspects of safe and fair resource use. Existing proposals for resource consumption targets are reviewed, partially revisited, and taken as a basis to outline potential target values for a safe operating space for the extraction and use of minerals and biomass by final consumption. A potential sustainability corridor is derived with the Total Material Consumption of abiotic resources ranging from 6 to 12 t/person, the Total Material Consumption of biotic resources not exceeding 2 t/person, and the Raw Material Consumption of used biotic and abiotic materials ranging from 3 to 6 t/person until 2050. For policy, a "10-2-5 target triplet" can provide orientation, when the three indicators are assigned values of 10, 2, and 5 t/person, respectively.

Description: A future-oriented and sustainable "Leasing Society" is based on a combination of new and innovative serviceoriented business models, changed product and material ownership structures, increased and improved eco-design efforts, and reverse logistic structures. Together these elements have the potential to change the relationship between producers and consumers, and thereby create a new incentive structure in the economy regarding the use and re-use of resources. While the consumer in a leasing society buys a service (instead of a product), the producer in a leasing society retains the ownership of the product (instead of selling it) and sells the service of using the product. This creates producer incentives to re-use, remanufacture, and recycle products and materials and could become a cornerstone of the circular economy, depending on how the leasing society is implemented. While a predominantly positive picture of the success of a leasing society model and related business cases emerges from the bigger part of the available literature, this paper argues that the resource efficiency of respective business cases is highly dependent on the specific business case design. This paper develops a more cautious and differentiated definition of the leasing society by discussing relevant mechanisms and success factors of leasing society business cases. The leasing society is discussed from a micro business-oriented and a macro environment-oriented perspective complemented by a discussion of conditions for successful business models that reduce environmental impacts and resource footprints.

Description: The German "Energiewende" (energy transition) is meant to be a contract between generations. The rebuilding of the whole energy system is designed and financed today in order to safeguard our children and grandchildren against fundamental risks: the enormous economic, social and environmental costs of a fossil-nuclear energy system, the risks of the nuclear fuel-cycle and the impacts of climate change, as well as energy import dependency, price shocks and geopolitical disputes over scarce resources. In contrast, a successful Energiewende creates new business areas and qualified jobs and increases competitiveness in the "green race" - in particular on the lead markets for efficiency technology and renewable energy. Accordingly, the Energiewende is described in this book as the collective effort of post-war German history and as a unique learning arena for a positive socio-economic transformation with international relevance. The book covers the formation of both the social and scientific Energiewende consensus, quantitative scenarios, the state of the Energiewende in 2015, the need for further policy intervention - in particular with respect to energy efficiency, and not least the integration of efficiency, sufficiency and renewable energy policies.

Description: Heating behavior of households is key for reducing domestic energy demand and mitigating climate change. Recently, various technical devices have been developed, providing households with feedback on their heating behavior and supporting energy conservation behavior. The impact of such devices on overall energy consumption depends on (1) the impact of a device within a household, (2) the diffusion of devices to other households and the number of adopters, and (3) the diffusion of the induced behavioral change beyond these households. While the first two processes are currently established in assessments of sustainable household devices, we suggest that adding behavior diffusion is essential when assessing devices that explicitly target behavioral change. We therefore propose an assessment framework that includes all three processes. We implement this framework in an agent-based model by combining two existing simulation models to explore the effect of adding behavior diffusion. In three simulation experiments, we identify two mechanisms by which behavior diffusion (1) spreads the effect of such devices from adopters to non-adopters and (2) increases the average speed of behavioral change of households. From these results we conclude that behavior diffusion should be included in assessments of behavior-changing feedback devices.

Description: Societal transitions involve multiple actors, changes in institutions, values and technologies, and interactions across multiple sectors and scales. Given this complexity, this paper takes on the view that the societal transitions research field would benefit from the further maturation and broader uptake of modelling approaches. This paper shows how modelling can enhance the understanding of and support stakeholders to steer societal transitions. It discusses the benefits modelling provides for studying large societal systems and elaborates on different ways models can be used for transitions studies. Two model applications are presented in some detail to illustrate the benefits. Then, limitations of modelling societal transitions are discussed, which leads to an agenda for future activities: (1) better cooperation in the development of dynamic models, (2) stronger interaction with other transition scholars and stakeholders, and (3) use of additional modelling approaches that we think are relevant to and largely unexplored in transitions studies.

Description: German electricity giants have recently taken high-level decisions to remove selected fossil fuel operations from their company portfolio. This new corporate strategy could be seen as a direct response to the growing global influence of the fossil fuel divestment campaign. In this paper we ask whether the divestment movement currently exerts significant influence on decision-making at the top four German energy giants - E.On, RWE, Vattenfall and EnBW. We find that this is not yet the case. After describing the trajectory of the global fossil fuel divestment campaign, we outline four alternative influences on corporate strategy that, currently, are having a greater impact than the divestment movement on Germany's power sector. In time, however, clear political decisions and strong civil support may increase the significance of climate change concerns in the strategic management of the German electricity giants.

Description: Social innovations, which transform resource intensive routines and practices into low-resource ones, combined with socio-technically designed transition paths, which are created around sustainability and environmental criteria, are milestones for implementation and diffusion of SCP (Sustainable Consumption and Production). This paper analyses such processes based on eight key components in order to evaluate and explain transformation and transition towards a sustainable lifestyle. Actors on all levels of society are included in this approach, creating a whole framework. Global megatrends, such as climate change, demographic change or resource scarcity will be put into relation with current policies and production trends, which play an important role for the development of transition pathways and future scenarios. This will enable us to work out guidelines and ideas on how to create a more sustainable society specifically.

Description: To identify the main drivers of transformation, it is helpful to identify the transformation perspectives of three specific schools of thought: idealist, institutional, and technological innovation. By differentiating among these schools of thought, a more informed transformation debate becomes possible, thereby increasing transformative literacy in academia and society.

Description: This work focuses on the observation of data recorded by the seismic temporary network installed in the Amatrice area, under the umbrella of the Italian Center for Seismic Microzonation (http://www.centromicrozonazionesismica.it), following the M 6.0 earthquake of August 24, 2016 in Central Italy. The aim was studying the presence of an evident late low frequency wave packet observed in some of the recorded aftershocks. In order to interpret this phenomenon, we combined a beam-forming analysis performed on these data with the statistics on residuals of localizations related to the same events, recorded by the Italian Seismic Network (RSN). The total number of analyzed events, characterized by M≥=3 and epicentral distances between 30 and 55 Km, is 356. By observing the seismic traces of these events there was an evidence, in some of them, of a low frequency packet appearing 10 seconds after the first arrival. The evidence of this packet was correlated with epicentral distance and focal depth. For a subset of stations, considered as an array, a beam-forming analysis was performed by using the ObsPy toolbox (M. Beyreuther et al., 2010). Results of this analysis gave information in terms of slowness and azimuth to distinguish the main seismic phases of the considered events. In addition, by using locations of the RSN records (Chiaraluce et al., 2017), we performed a parallel analysis within the subset of events with clear evidence of the low frequency packet. We relocated these events by using the NonLinLoc code, with a fixed 1D P-wave velocity model, and varying the Vp/ Vs ratio in the range 1.6–2.0. We found that the P phases residuals are not influenced by the Vp/Vs ratio changes whereas the higher the Vp/Vs the lower are the S phases residuals. Higher values of Vp/Vs ratio, fixing Vp values, could mean a decrease of Vs connected to particular effects during the seismic waves path, that are probably due to geological heterogeneities at local or larger scale

Description: Published

Description: Miami, Florida

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: The aim of scientific dissemination is to spread interest and knowledge of scientific issues by trying to reach people of all ages and social backgrounds. Simplifying, without trivializing, scientific concepts and making them attractive to the general public is therefore essential to achieve the previous objectives. For this purpose, it can be useful for scientists to work in close collaboration with artists, implementing new tools that can positively influence the emotional sphere and capture the attention of the people involved. Playful educational activity and visual language play a key role in this process, to convey interest and facilitate learning. An example of this approach are the educational laboratories structured as group games, in which great importance is given both to practical activities and to the transmission of concepts through their visualization in the form of images. Over the last 8 years, the Istituto Nazionale di Geofisica e Vulcanologia (National Institute of Geophysics and Volcanology, INGV), the Istituto di Scienze Marine del Consiglio Nazionale delle Ricerche (Institute of Marine Sciences of the National Research Council, CNR-ISMAR) and the Historical Oceanography Society (HOS) have collaborated in the organization of science dissemination events involving students from schools of different levels participating in educational experiences based on games, characterized by an essentially visual approach to the concepts presented. In this work, we would like to give a brief overview of these educational tools, retracing the choices made while ideating them, thanks mainly to the close collaboration with artists and illustrators.

Description: Published

Description: 179–190

Description: 2TM. Divulgazione Scientifica

Description: N/A or not JCR

Description: In recent years, great efforts have been devoted to the study of the human-induced earthquakes, owing to the effect that these earthquakes can have in terms of seismic hazard. In the past, different authors proposed classification schemes for distinguishing different mechanisms for fluid-induced seismicity generation (see, e.g. McGarr 2000). For example, it has been suggested that when the anthropic activities are responsible for a very small part of the stress field perturbations, the seismic events can be classified as “triggered”, while when the anthropic activities are responsible for the most of stress perturbations driving to the event occurrence, it can be classified as “induced”. In practice, we can rather consider that it may exist a continuum of cases depending on both the characteristics of technological operations and the local stress state.

Description: Ministero di Sviluppo Economico, Direzione Generale per le Infrastrutture e la Sicurezza dei Sistemi Energetici e Geominerari (DG ISSEG)

Description: Published

Description: Bologna

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: A total of 4991 ionograms recorded from April 1997 to December 2017 by the Millstone Hill Digisonde (42.6°N, 288.5°E) were considered, with simultaneous Ne(h)[ISR] profiles recorded by the co-located Incoherent Scatter Radar (ISR). The entire ionogram dataset was scaled with both the Autoscala and ARTIST programs. The reliability of the hmF2 values obtained by ARTIST and Autoscala was assessed using the corresponding ISR values as a reference. Average errors Δ and the root mean square errors RMSE were computed for the whole dataset. Data analysis shows that both the Autoscala and ARTIST systems tend to underestimate hmF2 values with |Δ| in all cases less than 10 km. For high magnetic activity ARTIST offers better accuracy than Autoscala, as evidenced by RMSE[ARTIST] 〈 RMSE[Autoscala], under both daytime and nighttime conditions, and considering all hours of the day. Conversely, under low and medium magnetic activity Autoscala tends to estimate hmF2 more accurately than the ARTIST system for both daytime and nighttime conditions, when RMSE[Autoscala] 〈 RMSE[ARTIST]. However, RMSE[Autoscala] slightly exceeds RMSE[ARTIST] for the day as a whole. RMSE values are generally substantial (RMSE 〉 16 km in all cases), which places a limit on the results obtainable with real-time models that ingest ionosonde data.

Description: Published

Description: id 2671

Description: 2A. Fisica dell'alta atmosfera

Description: JCR Journal

Description: Ionospheric characteristics and crustal earthquakes that occurred in 2016 next to the town of Amatrice, Italy are studied together with the previous events that took place from 1984 to 2009 in Central Italy. The earthquakes with M larger than 5.5 and epicentral distances from the ionosonde less than 150 km were selected for the analysis. A multiparametric approach was applied using variations of sporadic E-layer parameters (the height and the transparency frequency) together with variations of the F2 layer critical frequency foF2 at the Rome ionospheric observatory. Only ionospheric data under quiet geomagnetic conditions were considered. The inclusion of new 2016 events has allowed us to clarify the earlier-obtained seismo-ionospheric empirical relationships linking the distance in space (km) and time (days) between the ionospheric anomaly and the impending earthquake, with its magnitude. The improved dependencies were shown to be similar to those obtained in previous studies in different parts of the world. The possibility of using the obtained relationships for earthquake predictions is discussed.

Description: Published

Description: id 354

Description: 2A. Fisica dell'alta atmosfera

Description: JCR Journal

Description: The identification and characterization of seismogenic structures in southwestern Sicily is an open debate both for the geological-structural complexity of this sector and the scarce seismicity as well. In addition, clear morphological evidence of tectonic structures is limited. Besides the geophysical methods, the study of the spatial distribution of soil CO2 flux is a valid methodology to investigate the position and geometry of buried active faults. Indeed, active tectonic structures are channels with high permeability through which deep fluids can migrate toward the atmosphere. Therefore, the alignment of high degassing areas can reveal the presence of preferential ways of rising fluids (i.e. faults). We applied this methodology in SW Sicily in the surrounding of the area hit by the 1968 seismic sequence and in three other areas where evidence of active deformation has been recognized. Furthermore, to investigate the origin of emitted fluids, we measured the carbon isotopic composition of the soil CO2 in some high emission sites. The results showed high spatial variability of soil CO2 fluxes with values ranging from 1 to 430 g m−2d−1. The areal patterns of soil CO2 fluxes in all the areas reveal a strong influence of the main tectonic structures and active deformations on soil CO2 emissions. The range of isotopic data and the distribution of soil CO2 fluxes suggest a supply of deep fluids through the active tectonic structures.

Description: Published

Description: SE104

Description: 2T. Deformazione crostale attiva

Description: 6A. Geochimica per l'ambiente e geologia medica

Description: JCR Journal

Description: Paleo-thermometers in sedimentary basins often drive to misleading thermal modelling when applied alone or only on potentially productive Paleozoic source rocks. Different paleo-thermal and thermo-chronological data have been used as constraints to model the Silurian to Cenozoic succession of a recently drilled well in the onshore portion of the Baltic Basin, in northern Poland. This dataset provides an integrated platform for thermal maturity assessment contributing to the highly debated reconstruction of the thermal history of the Baltic Basin in the last decade. The well stratigraphy consists of a Lower Paleozoic marine clayey and arenaceous/calcareous succession, about 1000 m thick that is unconformably overlain by a 2000 m thick Permian to Cenozoic sequence, developed in a continental to shallow marine environment. Optical microscopy, FT-IR and Raman spectroscopy analysis of organic matter have been coupled with (U–Th)/He data to produce a robust vitrinite reflectance profile and constrain the 1D thermal modelling of the well. In addition, such a thermal maturity profile was validated by an independent thermal modelling calibrated by the smectite illitization kinetics. Both models identify high heat flow conditions (up to 1.7 HFU) at the end of Mesozoic. The Lower Paleozoic succession entered the late oil window of HC generation during this last heating event.

Description: Published

Description: 104547

Description: 1TR. Georisorse

Description: JCR Journal

Description: The Einstein Telescope (ET) is a proposed next-generation, underground gravitational-wave detector to be based in Europe. It will provide about an order of magnitude sensitivity increase with respect to the currently operating detectors and, also extend the observation band targeting frequencies as low as 3 Hz. One of the first decisions that needs to be made is about the future ET site following an in-depth site characterization. Site evaluation and selection is a complicated process, which takes into account science, financial, political, and socio-economic criteria. In this paper, we provide an overview of the site-selection criteria for ET, provide a formalism to evaluate the direct impact of environmental noise on ET sensitivity, and outline the necessary elements of a site-characterization campaign.

Description: Published

Description: 094504

Description: 6IT. Osservatori non satellitari

Description: JCR Journal

Description: Recent strontium isotope (87Sr/86Sr) analyses of bones and teeth have provided useful archeological results for reconstructing past human migration and diet. We report 87Sr/86Sr ratios and DNA analyses of tooth enamel from individuals buried in some necropolises in Nola town, near Napoli (Campania, South Italy). These individuals lived in the period between the Avellino (1925 years BCE) and CE 472 Pollena Vesuvian eruptions and are dated on archeological basis to the time span between the sixth and second century BCE. Tooth enamel 87Sr/86Sr ratios (0.70788–0.70864) are higher than baseline values in the necropolises (0.70756–0.70792): this can be explained by assuming either that all the analyzed individuals are not local—an unlikely possibility—or that they ate both local and foreign food (within about 50 km), including 87Sr-rich seafood. An explanation for such a varied diet might be that the individuals from Nola were living near the Ancient Appia and Popilia ways and not far from the coastline. Whatever its origin, the 87Sr/86Sr ratios represent the isotopic signature of the local community living on the slopes of Mt. Somma-Vesuvius between the sixth and second centuries BCE. This knowledge will support future isotope studies on volcanic eruptions as possible causes of human migration.

Description: Published

Description: id 157

Description: 1V. Storia eruttiva

Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: JCR Journal

Description: DOWNFLOW is a probabilistic code for the simulation of the area covered by lava flows. This code has been used extensively for several basaltic volcanoes in the last decade, and a review of some applications is presented. DOWNFLOW is based on the simple principle that a lava flow tends to follow the steepest descent path downhill from the vent. DOWNFLOW computes the area possibly inundated by lava flows by deriving a number, N, of steepest descent paths, each path being calculated over a randomly perturbed topography. The perturbation is applied at each point of the topography, and ranges within the interval +Dh. N and Dh are the two basic parameters of the code. The expected flow length is constrained by statistical weighting based on the past activity of the volcano. The strength of the code is that: (i) only limited volcanological knowledge is ecessary to apply the code at a given volcano; (ii) there are only two (easily tunable) input parameters; and (iii) computational requirements are very low. However, DOWNFLOW does not provide the progression of the lava emplacement over time. The use of DOWNFLOW is ideal when a large number of simulations are necessary: for example, to compile maps for hazard and risk-assessment purposes.

Description: Published

Description: 293-312

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: We compare differences and similarities in the annual stratospheric HNO3 cycle derived from ground‐based measurements at the South Pole during 1993 and 1995, after correcting an error in earlier published profile retrievals for 1993 which led to under estimation of mixing ratios. The data series presented here provide profiling over the range ∼16–48 km, and cover the fall‐winter‐spring cycle in the behavior of HNO3 in the extreme Antarctic with a large degree of temporal overlap. With the exception of one gap of 20 days, the combined data sets cover a full annual cycle. The record shows an increase in HNO3 above 30 km occurring about 20 days before sunset, which appears to be the result of higher altitude heterogeneous conversion of NOx as photolysis diminishes. Both years show a strong increase in HNO3 beginning about polar sunset, in a layer peaking at about 25 km, as additional NOx is heterogeneously converted to nitric acid. When temperatures drop to the polar stratospheric cloud (PSC) formation range near the end of May, gas phase HNO3 is rapidly reduced in the lower stratosphere, although at least 2–3 weeks of temperatures ≤192 K appear to be required to complete most of the gas‐phase removal at the upper end of the depletion range (22–25 km). Despite a significant difference in residual sulfate loading from the explosion of Mount Pinatubo, there appears to be little gross difference in the timing and effects of PSC formation in removing gas phase HNO3 in these 2 years, though removal may be more rapid in 1995. Incorporation of gas phase HNO3 into PSCs appears to be nearly complete up to ∼25 km by midwinter. We also see a repeat of the formation of gas phase HNO3 in the middle stratosphere in early midwinter of 1995 with about the same timing as in 1993, suggesting that this phenomenon is driven by a repetition of dynamical transport and appropriate temperatures and pressures in the polar night, and not (as has been suggested) by ion‐based heterogeneous chemistry that requires triggering by large relativistic electron fluxes. High‐altitude HNO3 production peaks during a period of ∼20 days, but appears to persist for up to ∼40 days in the 40–45 km range, ceasing well before sunrise. This HNO3 descends rapidly throughout the production period, at a rate in good agreement with theoretically determined midwinter subsidence rates. As noted in earlier studies, later warming of this region above PSC evaporation temperatures does not cause reappearance of large amounts of HNO3, indicating that most PSCs gravitationally sink out of the stratosphere before early spring. We present evidence that smaller PSCs do evaporate to ∼1 to 3.5 ppbv of HNO3 in the lower stratosphere, however, working downward from ∼25 km as temperatures rise during the late winter. There is a delay of ∼15 days after sunrise before photolysis causes significant depletion in the altitude range below ∼30 km, where subsidence has carried virtually all higher‐altitude HNO3 by polar sunrise. Some continued subsidence and photolysis combine to keep mixing ratios less than ∼5 ppbv below 30 km until the final breakdown of the vortex in November brings larger amounts of HNO3 with air from lower latitudes.

Description: Published

Description: 17739-17750

Description: 5A. Ricerche polari e paleoclima

Description: JCR Journal

Description: The vulnerability assessment on large areas was carried out on residential buildings adopting a statistical approach that has been developed for this purpose. In fact, even though the method for evaluating single buildings vulnerability is quite well defined, it cannot be applied to large areas, not only because it would cost too much in money and time to survey each building, but also because the result would be useless at this scale, where the information needed for decision making is less detailed. Census data are a primary source in this case: they cover homogeneously the whole country though the information they provide permits only to estimate the total number of buildings, the total volume and a poor classification in terms of age and few typological parameters. The collection and review of available data regarding previous buildings vulnerability surveys performed by GNDT and census archives has been organised inside a database for the calibration of buildings vulnerability functions in the investigated area. The vulnerability evaluation for all Italian municipalities has been performed as a weighted mean of the average vulnerability index for each census classes.

Description: Published

Description: 105-131

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: The Italian Present-day Stress Indicators (IPSI) database is a freely available Italian georeferenced repository of information regarding the crustal stress field. It consists of horizontal stress orientations that have been analysed, compiled in a standardised format and quality-ranked for reliability and comparability on a global scale. The database contains a collection of information regarding contemporary stress within the shallow crust from the following main stress-indicator categories: borehole breakouts; earthquake focal mechanisms; seismic sequences and active fault-slip data. The present database (IPSI 1.4) released in January 2020 is accessible through a web interface which facilitates findability, accessibility, interoperability and reusability of the dataset. Moreover, it contains 928 records updated up until December 2019 with an increase of 10% with respect to the first one, and improved metadata information. The uniform spread of stress data over a given territory is relevant for earth crustal modelling or as starting point in many applied studies. It is therefore necessary to continue collecting new data and update present-day stress maps to obtain more reliable evaluations.

Description: Published

Description: id 298

Description: 2T. Deformazione crostale attiva

Description: 4IT. Banche dati

Description: JCR Journal

Description: Establishing sustainable and responsible speleotourism development is a major challenge and involves complex activities. Adequate theoretical starting point is the application of geoethical values related to the conservation and protection of the caves to be used for touristic purposes. Positive and negative cases of human behaviors towards speleological geoheritage are discussed, in order to highlight what should be done in cave management to avoid malpractices and on what elements could be founded adequate strategies aimed at promoting sustainable speleotourism. This is important to tourism management organizations involved in the promotion of caves and in creating economic opportunities for local populations, while respecting cave ecosystems. Modern cave management must be focused on the protection of the cave ecosystems, finding ways to achieve at the same time an economic development of local communities. But this approach needs the adoption of a geoethical framework of values to be shared by all stakeholders involved so that successful cooperation can be achieved despite differences in interests and expectations. The aim of this paper is to raise the awareness about the need to apply the values of geoethics to speleotourism, stimulating new fields of discussion within the scientific and technical communities involved in studies and activities related to geotourism and geoheritage. The possibilities of developing new ways to manage caves, in order to promote a sustainable socio-economic development of local communities, have to be balanced with the protection of natural environments as much as possible. The proposed theoretical frameworks have the goal to increase the discussion on the best ways of connecting speleotourism to sustainable and responsible cave management, presenting two case studies, and pointing out potential solutions.

Description: Open access funding provided by Istituto Nazionale di Geofisica e Vulcanologia within the CRUI-CARE Agreement

Description: Published

Description: id 73

Description: 7SR AMBIENTE – Servizi e ricerca per la società

Description: 1TM. Formazione

Description: 2TM. Divulgazione Scientifica

Description: JCR Journal

Description: A high-resolution (1 km line spacing) aerogeophysical survey was conducted over a region near the East Antarctic Ice Sheet’s Dome C that may hold a 1.5 Myr climate record. We combined new ice thickness data derived from an airborne coherent radar sounder with unpublished data that was in part unavailable for earlier compilations, and we were able to remove older data with high positional uncertainties. We generated a revised high-resolution digital elevation model (DEM) to investigate the potential for an old ice record in this region, and used laser altimetry to confirm a Cryosat-2 derived DEM for inferring the glaciological state of the candidate area. By measuring the specularity content of the bed, we were able to find an additional 50 subglacial lakes near the candidate site, and by Doppler focusing the radar data, we were able to map out the roughness of the bed at length scales of hundreds of meters. We find that the primary candidate region contains elevated rough topography interspersed with scattered subglacial lakes and some regions of smoother bed. Free subglacial water appears to be restricted from bed overlain by ice thicknesses of less than 3000 m. A site near the ice divide was selected for further investigation. The high resolution of this ice thickness data set also allows us to explore the nature of ice thickness uncertainties in the context of radar geometry and processing.

Description: Published

Description: 1897-1911

Description: 5A. Paleoclima e ricerche polari

Description: JCR Journal

Description: Exploring different degrees of complexities in the geometry of seismic tsunami sources is a key point to optimize Probabilistc Tsunami Hazard Analyis (PTHA), as fault geometry can have an impact on the generated tsunami. In this regard, one major difficulty is represented by the potentially tsunamigenic offshore faults that are generally poorly constrained and consequently the geometry is often oversimplified as a planar fault. We present compared scenarios of PTHA for ruptures located in the Calabrian subduction interface using different source models. The Calabrian subduction, located in the Mediterranean Sea, has occasionally be blamed to have generated some past large earthquakes and tsunamis, despite it shows no sign of significant seismic activity on the shallow portion of the interface. Significant in-slab seismicity is recorded below 40 km depth and a rate of 1-5 mm/yr characterize the convergence between the two plates involved, Africa and Europe. A 3D model of the subduction interface was obtained from the original interpretation of a grid of ca. 60 (9000 km length) seismic reflection profiles (Spectrum – INGV collaborative framework CA-60) coupled with the detailed analysis of the seismicity, providing a highly detailed 3D surface geometry for the first 100 km depth. This model includes both the first order information on the curvature and changes in strike and an accurate reconstruction of the 3D subduction interface, and can be scaled to different levels of detail. We compare simplified planar vs 3D models with different degrees of geometrical complexities in order to estimate the effect of the source geometry on the tsunami generation and propagation pattern.

Description: TSUMAPS-NEAM Project, co-financed by the European Union Civil Protection Mechanism, Agreement Number: ECHO/SUB/2015/718568/PREV26; Italian Flagship Project RITMARE

Description: Unpublished

Description: Wien

Description: 5T. Modelli di pericolosità sismica e da maremoto

Description: Turrialba volcano lies in the southern sector of the Central American Volcanic Front (CAVF) in Costa Rica. The geochemistry of major and trace elements, and Sr and Nd isotopes of a selected suite of volcanic rocks ranging in composition from basaltic andesite to dacite and belonging to the last 10 ka of activity of Turrialba volcano is described, together with the He-, Ne-, and Ar-isotope compositions of fluid inclusions hosted in olivine and pyroxene crystals. Most of the variability in the rock chemistry is consistentwith typical trends of fractional crystallization, but there is an outlying group of andesites that displays an adakite-like composition (with a consistent depletion in high-field-strength elements and a marked enrichment in Sr) and low 3He/4He ratios (7.0–7.2 Ra). The trace-element composition of these rocks is typical of subduction-related magmas influenced by an OIB-like component at the source associated with the subduction of the Galapagos seamounts. The 87Sr/86Sr (0.703612–0.703678) and 143Nd/144Nd (0.512960–0.512984) ratios of the bulk rocks vary within narrowranges, and are among the least-radiogenic isotope signatures of the CAVF volcanoes. The 3He/4He ratios measured in fluid inclusions hosted in olivine crystals (up to 8.1 Ra) are among the highest for the CAVF, and indicate that radiogenic 4He from fluids derived fromthe subducting slab contribute negligibly to the mantle wedge. The difference in He isotopes between most of studied rocks and those showing adakite-like features reasonably reflects two distinct components in the local mantle: (1) a MORB-like component, characterized by the highest He-isotope ratios (7.8–8.1 Ra), and (2) an OIB-like component, characterized by lower He-isotope ratios (7.0–7.2 Ra), coming from the subduction of the Galapagos seamounts. An overview at the regional scale indicates that high He-isotope ratios are peculiar to the two extreme sectors of the CAVF (Costa Rica to the south and Guatemala to the north), whereas in the central sector (Nicaragua) the magma source is probably contaminated by slab fluids. For the past few years Turrialba volcano has been in a volcanic unrest phase that has included a series of explosions, the most recent of which occurred between October 2014 and May 2015. The volcano is subject to an ongoing safety alert due to the possibility of a magmatic eruption. One of the crucial questions to be addressed is the kind of eruption that can be expected, and hence what type of magma is likely to be involved. The high 3He/4He ratios (7.8–8.0 Ra) measured during 2011 at high-temperature fumaroles of Turrialba craters are comparable to those measured in fluid inclusions of basaltic andesites that erupted in 1864–1866, suggesting that the magma currently feeding the shallow plumbing system has similar geochemical characteristics to the most recently erupted magma.

Description: Published

Description: 319-335

Description: 1V. Storia e struttura dei sistemi vulcanici

Description: 2V. Dinamiche di unrest e scenari pre-eruttivi

Description: JCR Journal

Description: restricted

Description: We model interevent times and Coulomb static stress transfer on the rupture segments along the Corinth Gulf extension zone, a region with a wealth of observations on strong-earthquake recurrence behavior. From the available information on past seismic activity, we have identified eight segments without significant overlapping that are aligned along the southern boundary of the Corinth rift. We aim to test if strong earthquakes on these segments are characterized by some kind of time-predictable behavior, rather than by complete randomness. The rationale for time-predictable behavior is based on the characteristic earthquake hypothesis, the necessary ingredients of which are a known faulting geometry and slip rate. The tectonic loading rate is characterized by slip of 6 mm/yr on the westernmost fault segment, diminishing to 4 mm/yr on the easternmost segment, based on the most reliable geodetic data. In this study, we employ statistical and physical modeling to account for stress transfer among these fault segments. The statistical modeling is based on the definition of a probability density distribution of the interevent times for each segment. Both the Brownian Passage-Time (BPT) and Weibull distributions are tested. The time-dependent hazard rate thus obtained is then modified by the inclusion of a permanent physical effect due to the Coulomb static stress change caused by failure of neighboring faults since the latest characteristic earthquake on the fault of interest. The validity of the renewal model is assessed retrospectively, using the data of the last 300 years, by comparison with a plain time-independent Poisson model, by means of statistical tools including the Relative Operating Characteristic diagram, the R-score, the probability gain and the log-likelihood ratio. We treat the uncertainties in the parameters of each examined fault source, such as linear dimensions, depth of the fault center, focal mechanism, recurrence time, coseismic slip, and aperiodicity of the statistical distribution, by a Monte Carlo technique. The Monte Carlo samples for all these parameters are drawn from a uniform distribution within their uncertainty limits. We find that the BPT and the Weibull renewal models yield comparable results, and both of them perform significantly better than the Poisson hypothesis. No clear performance enhancement is achieved by the introduction of the Coulomb static stress change into the renewal model.

Description: Published

Description: 3655–3673

Description: 5T. Modelli di pericolosità sismica e da maremoto

Description: 6T. Variazioni delle caratteristiche crostali e precursori

Description: JCR Journal

Description: We compare the performances of linear and non-linear hypocentre location methods working in 3-D velocity structures, a not-fully explored subject of main interest in the regions where the location problem is ill-conditioned. Comparisons are made between the linear location method known as SIMUL and the non-linear probabilistic algorithm named BAYLOC, using the data sets of the two main seismic sequences which occurred in the last decade in the southern Tyrrhenian Sea. We find that in the suboptimal network conditions of these sequences the SIMUL and BAYLOC algorithms furnish hypocentre coordinates of comparable accuracy leading to similar hypocentre spatial trends, while the location error estimates from SIMUL are, in general, less accurate than BAYLOC's. These findings are further supported by locations of synthetic events performed in the same network-model conditions of the real sequences. We conclude that linearized methods produce lower quality location error estimates but no overall bias in the hypocentral coordinates compared to non-linear methods. Therefore, we extend to 3-D location a conclusion drawn by previous investigators for 1-D location. Because location error estimates may be crucial to establish whether the hypocentre trend of a sequence does really mark the seismogenic structure or simply reflects ill-conditioning of the location process, we based on the BAYLOC probabilistic algorithm our approach to hypocentre trend evaluation for seismogenic fault detection. This procedure, named ISO-TEST, works through isotropic generation of synthetic hypocentres inside the sequence volume (simulations) and comparison by misfit variables of the location probability function of the sequence with probability functions from simulations. The application of ISO-TEST showed that while the NE–SW trend of one of the study sequences can only in minor part be ascribed to ill-conditioning of the location process, and then it may reasonably be proposed as the signature of the source, the NW–SE trend of the other is contaminated in a greater percentage by the location process, and we are led to conclude that source detection is doubtful in this case.

Description: Published

Description: 607–618

Description: 4T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: JCR Journal

Description: Mount Etna is the highest relief in Sicily and represents a unique environment because of its long established and almost continuous eruptive activity, that has moulded its landforms and which has produced distinctive landscapes. Over the past 60 ka both destructive and constructive geological processes have produced the principal morphological features of the volcano such as the wide Valle del Bove depression, monogenic scoria cones and extensive lava flow fields. Relationships between Etna, its environment and human activity began in the Neolithic Period within the mountain foot region and have developed over millennia. Even though there has been a rapid rate of resurfacing by lava during historic times, the impact on human activity has been short-lived, recovery has been rapid and society has adjusted to the ever present hazard in distinctive ways.

Description: Published

Description: 467-478

Description: 1V. Storia eruttiva

Description: N/A or not JCR

Description: This article has been accepted for publication in Geophysical Journal Internationa ©: 2017 Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.

Description: We present a 2-D subsurface image of the Paganica Fault from a high-resolution refraction tomography and detailed geological investigation carried out across part of the northwestern segment of the 20-km-long Paganica–San Demetrio fault-system, and which was responsible of the 2009 April 6 Mw 6.1 L’Aquila earthquake (central Italy). We acquired two seismic profiles crossing the Paganica basin with a dense-wide aperture configuration. More than 30 000 P wave first-arrival traveltimes were input to a non-linear tomographic inversion. The obtained 250–300 m deep 2-D Vp images illuminate the shallow portion of the Paganica Fault, and depict additional unreported splays defining a complex half-graben structure. We interpret local thickening of low-Vp (〈2400 m s−1) and intermediate-Vp (2600–3400 m s−1) regions as syn-tectonic clasticwedges above a high-Vp (3800–5000ms−1) carbonate basement. These results are condensed in a 4.2-km-long section across the Paganica basin, clearly indicating that the Paganica Fault is a mature normal fault cutting the whole upper ∼10 km of the crust. We evaluate a minimum cumulative net displacement of 650 ± 90 m and a total heave of 530 ± 65 m accomplished by the Paganica Fault, respectively. In the conservative hypothesis that the extension started during the Gelasian (1.80–2.59 Ma),we obtain a minimum long-term slip-rate of 0.30 ± 0.07 mm yr−1 and an extension-rate of 0.25 ± 0.06 mm yr−1, respectively. Considering the regional averaged extensional field of ∼1 mm yr−1 obtained from geodetic and geological analyses at 104 yr timescale, we infer that the Paganica Fault accounts for ∼20 per cent of the NE-extension affecting this zone of the central Apennines axis due to the concurrent activity of other parallel normal fault-systems nearby (e.g. the Liri, Velino-Magnola, L’Aquila-Celano and Gran Sasso fault-systems).

Description: Published

Description: 403-423

Description: 1T. Deformazione crostale attiva

Description: JCR Journal

Description: Assessment of the ongoing activity of volcanoes is one of the key factors to reduce volcanic risks. In this paper, two Machine Learning (ML) approaches are presented to classify volcanic activity using multivariate geophysical data, namely the Decision Tree (DT) and K-Nearest Neighbours (KNN). The models were implemented using a data set recorded at Mount Etna (Italy), in the period 01 January 2011 – 31 December 2015, encompassing lava fountain events and intense Strombolian activity. Here a data set consisting of five geophysical features, namely the root-mean-square of seismic tremor (RMS) and its source depth, counts of clustered infrasonic events, radar RMS backscattering power and tilt derivative, was considered. Model performances were assessed by using a set of statistical indices commonly considered for classification approaches. Results show that between the investigated approaches the DT model is the most appropriate for classification of volcano activity and is suitable for early warning systems applications. Furthermore, the comparison with a different classifier approach, reported in literature, based on Bayesian Network (BN), is performed.

Description: Published

Description: VO231

Description: 1V. Storia eruttiva

Description: JCR Journal

Description: Recent Global Positioning System observations of major earthquakes such as the 2014 Chile megathrust show a slow preslip phase releasing a significant portion of the total moment (Ruiz et al., 2014, https://doi.org/10.1126/science.1256074). Despite advances from theoretical stability analysis (Rubin & Ampuero, 2005, https://doi.org/10.1029/2005JB003686; Ruina, 1983, https://doi.org/10.1029/jb088ib12p10359) and modeling (Kaneko et al., 2017, https://doi.org/10.1002/2016GL071569), it is not fully understood what controls the prevalence and the amount of slip in the nucleation process. Here we present laboratory observations of slow slip preceding dynamic rupture, where we observe a dependence of nucleation size and position on the loading rate (laboratory equivalent of tectonic loading rate). The setup is composed of two polycarbonate plates under direct shear with a 30‐cm long slip interface. The results of our laboratory experiments are in agreement with the preslip model outlined by Ellsworth and Beroza (1995, https://doi.org/10.1126/science.268.5212.851) and observed in laboratory experiments (Latour et al., 2013, https://doi.org/10.1002/grl.50974; Nielsen et al., 2010, https://doi.org/10.1111/j.1365-246x.2009.04444.x; Ohnaka & Kuwahara, 1990, https://doi.org/10.1016/0040-1951(90)90138-X), which show a slow slip followed by an acceleration up to dynamic rupture velocity. However, further complexity arises from the effect of (1) rate of shear loading and (2) inhomogeneities on the fault surface. In particular, we show that when the loading rate is increased from 10−2 to 6 MPa/s, the nucleation length can shrink by a factor of 3, and the rupture nucleates consistently on higher shear stress areas. The nucleation lengths measured fall within the range of the theoretical limits Lb and urn:x-wiley:jgrb:media:jgrb53198:jgrb53198-math-0001 derived by Rubin and Ampuero (2005, https://doi.org/10.1029/2005JB003686) for rate‐and‐state friction laws.

Description: Published

Description: 689-708

Description: 2T. Sorgente Sismica

Description: 2IT. Laboratori analitici e sperimentali

Description: JCR Journal

Description: The CO2 flux provided by the hydrothermal activity within the Karymsky Volcanic Centre, Kamchatka, was measured, and the CO2 balance of the Karymsky caldera lake was estimated in the framework of a Deep Carbon Observatory (DCO) project. The Karymsky Volcanic Centre located in the SE of the Kamchatka Peninsula, in the middle of the modern volcanic front, consists of two calderas, hosts a caldera lake and is characterized by hydrothermal activity that is manifested at several thermal fields. Within the Akademii Nauk (AN) caldera which is filled by a caldera lake, the Akademii Nauk springs discharge boiling water into the lake. The lake is drained by the Karymsky River that then crosses the caldera of the Karymsky volcano (Karymsky caldera) and drains the thermal field of CO2-rich Karymsky springs. The lake after the 1996 sublimnic eruption is in a steady-state condition with the total dynamic CO2 budget of about 4 t/day, and has a total amount of CO2 stored inside of the lake of around 8000 t. The thermal springs of the Karymsky caldera drained by the Karymsky River enrich the river in dissolved carbon species. A total CO2 output of 320 t/day from both Karymsky Centre calderas was estimated, carrying around 130 t/day carbon species (expressed as CO2) as dissolved species (HCO3 and CO2(aq)), and emitting to the atmosphere around 190 t/day of CO2 as the diffusion flux fromthe soil and bubbling emanations from the springs.

Description: Published

Description: 1-9

Description: 3V. Proprietà dei magmi e dei prodotti vulcanici

Description: JCR Journal

Description: This work investigates physical mechanisms triggering phase scintillations on L-band signals under strong stormy conditions. Thanks to selected ground-based Global Navigation Satellite Systems (GNSS) receivers, located both in Antarctica and in the Arctic, an interhemispheric comparison between high latitude ionospheric observations in response to the peculiar solar wind conditions occurred on June 22, 2015 is here shown. To trace back the observed phase scintillations to the physical mechanisms driving it, we combine measurements from GNSS receivers with in-situ and ground-based observations. Our study highlights the ionospheric scenario in which irregularities causing scintillation form and move, leveraging on a multi-observation approach. Such approach allows deducing that scintillations are caused by the presence of fast-moving electron density gradients originated by particle precipitation induced by solar wind variations. In addition, we show how the numerous and fast oscillations of the north-south component of the interplanetary magnetic field (Bz,IMF) result to be less effective in producing moderate/intense scintillation events than during period of long lasting negative values. Finally, we also demonstrate how the in-situ electron density data can be used to reconstruct the evolution of the ionospheric dynamics, both locally and globally.

Description: Published

Description: GM454

Description: 2A. Fisica dell'alta atmosfera

Description: JCR Journal

Description: Fluids are pervasive in fault zones cutting the Earth's crust; however, the effect of fluid viscosity on fault mechanics is mainly conjectured by theoretical models. We present friction experiments performed on both dry and fluid-permeated silicate and carbonate bearing-rocks, at normal effective stresses up to 20 MPa, with a slip-rate ranging between 10 μm/s and 1 m/s. Four different fluid viscosities were tested. We show that both static and dynamic friction coefficients decrease with viscosity and that dynamic friction depends on the dimensionless Sommerfeld number (S) as predicted by the elastohydrodynamic-lubrication theory (EHD).Under favourable conditions (depending on the fluid viscosity (η), co-seismic slip-rate (V), fault geometry (L/H02) and earthquake nucleation depth (∝σeff)), EHD might be an effective weakening mechanism during natural and induced earthquakes. However, at seismic slip-rate, the slip weakening distance (Dc) increases markedly for a range of fluid viscosities expected in the Earth, potentially favouring slow-slip rather than rupture propagation for small to moderate earthquakes.

Description: Published

Description: 1274

Description: 3T. Sorgente sismica

Description: 2IT. Laboratori analitici e sperimentali

Description: JCR Journal

Description: In the first months of 2018, a parametric table (flatfile) related to the Engineering Strong Motion (ESM) database was released and disseminated through a website (http:// esm.mi.ingv.it/flatfile-2018). The flatfile contains intensity measures of engineering interest and associated metadata of three-components manually processed waveforms. The uniform collection of strong motion data and the compiling of quality-checked metadata allow the users among practitioners and seismologists, to test and calibrate Ground Motion Models (GMMs) for hazard assessment purposes or for the analysis of the seismic structural response. In 2013, a database used for similar purposes was constructed in the framework of the NGA-West2 project, whose main objective is to update and improve the Next Generation Attenuation (NGA) models for active tectonic regions, such as California. In this framework, a flatfile containing several parameters, such as peak parameters and ordinates of the pseudo-acceleration elastic response spectra, along with metadata of events and stations was released. The scope of this paper is to highlight the main differences between the two tables in terms of structure, data statistics and qualification of metadata.

Description: Published

Description: 343-356

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: 6T. Studi di pericolosità sismica e da maremoto

Description: JCR Journal

Description: Escape Volcano is a new scientific game that, through a path made of boxes, allows children andteenagers to question themselves and learn about issues related to the Earth Sciences and the risksassociated.The game is the brainchild of the INGV researchers of Rome who designed it, in close collaborationwith students from two third­year classes at the “Primo Levi” Scientific High School in Rome, as partof the Alternanza Scuola Lavoro (hereafter ASL) project “Life as a Researcher”; this educational­ludicsociety game deals, with the basic knowledge of volcanoes and earthquakes, providing ideas for themitigation of the risks associated with them, with purpose of environmental protection. In thefollowing will be illustrate the different phases that led the transformation of the original idea in toa project, as well as the realization of the “Prototype 00” carried out in the laboratories of the INGV.During the planning phase, the game was designed for boys of secondary school.The results obtained during this test phase, that was carried out for a year in various scientific events,allowed gathering excellent hints, in the terms of scientific content and rules. These advices permittedto improve the game fluidity and made it accessible for players of all ages, as well as for childrenwith different types of disabilities that necessitate special attention.

Description: Istituto Nazionale di Geofisica e Vulcanologia

Description: Published

Description: 1-34

Description: 1TM. Formazione

Description: 2TM. Divulgazione Scientifica

Description: 3TM. Comunicazione

Description: N/A or not JCR

Description: Questa nota descrive i diversi luoghi d’Italia attraversati da Giuseppe Mercalli ripercorrendo il percorso scientifico di questo famoso studioso, che, attraverso la meticolosa descrizione dei più disparati fenomeni naturali, era alla continua ricerca della loro spiegazione, classificazione e quantificazione. Questa sua continua ricerca lo portò ad approfondire, tra l’altro, tematiche vulcanologiche e sismologiche e ad inserirsi brillantemente nel dibattito scientifico dell’epoca. Di notevole rilievo furono anche la sua attività come insegnante e la sua produzione scientifica e “didattica”. Infatti egli non abbandonò mai l’insegnamento delle Scienze Naturali, che lo portò ad attraversare l’Italia e a dotare i propri allievi di libri di testo di notevole valore e accuratezza [Mercalli, 1883a; Mercalli, 1883b; Mercalli, 1883c; Mercalli, 1883d; Mercalli, 1883e; Mercalli, 1907]. Giuseppe Mercalli nacque a Milano il 20 Maggio del 1850, da Carlo e da Carolina De Simone, artigiani tessili della seta. Terzogenito di cinque figli, iniziò privatamente i suoi studi, proseguendo quelli liceali nel Seminario di Monza per la cultura letteraria e scientifica, e quelli teologici nel Seminario Maggiore di Milano, dove ricevette l’ordinazione sacerdotale il 20 dicembre 1872 (Fig. 1). Nella Sezione Normale del Politecnico milanese, Mercalli frequentò le lezioni del corso di Scienze Naturali tenute dal geologo abate Antonio Stoppani. Qui ottenne nel 1874 il diploma di insegnante di Scienze Naturali.

Description: Published

Description: 40-49

Description: 2TM. Divulgazione Scientifica

Description: N/A or not JCR

Description: La valorizzazione del territorio passa necessariamente attraverso la possibilità di mettere in luce le eccellenze che lo rendono un patrimonio unico attraverso l'integrazione tra di esse.....

Description: Published

Description: 1-16

Description: 2TM. Divulgazione Scientifica

Description: Nitrogen is the main constituent of the Earth's atmosphere, but its provenance in the Earth's mantle remains uncertain. The relative contribution of primordial nitrogen inherited during the Earth's accretion versus that subducted from the Earth's surface is unclear1-6. Here we show that the mantle may have retained remnants of such primordial nitrogen. We use the rare 15N15N isotopologue of N2 as a new tracer of air contamination in volcanic gas effusions. By constraining air contamination in gases from Iceland, Eifel (Germany) and Yellowstone (USA), we derive estimates of mantle δ15N (the fractional difference in 15N/14N from air), N2/36Ar and N2/3He. Our results show that negative δ15N values observed in gases, previously regarded as indicating a mantle origin for nitrogen7-10, in fact represent dominantly air-derived N2 that experienced 15N/14N fractionation in hydrothermal systems. Using two-component mixing models to correct for this effect, the 15N15N data allow extrapolations that characterize mantle endmember δ15N, N2/36Ar and N2/3He values. We show that the Eifel region has slightly increased δ15N and N2/36Ar values relative to estimates for the convective mantle provided by mid-ocean-ridge basalts11, consistent with subducted nitrogen being added to the mantle source. In contrast, we find that whereas the Yellowstone plume has δ15N values substantially greater than that of the convective mantle, resembling surface components12-15, its N2/36Ar and N2/3He ratios are indistinguishable from those of the convective mantle. This observation raises the possibility that the plume hosts a primordial component. We provide a test of the subduction hypothesis with a two-box model, describing the evolution of mantle and surface nitrogen through geological time. We show that the effect of subduction on the deep nitrogen cycle may be less important than has been suggested by previous investigations. We propose instead that high mid-ocean-ridge basalt and plume δ15N values may both be dominantly primordial features.

Description: Published

Description: 367–371

Description: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici

Description: JCR Journal

Description: Vulcano is one of the 7 volcanic islands and 6 seamounts forming the Aeolian volcanic district (Italy). Vulcano has a long eruptive record, and its last eruption (1888–90 AD) originated the definition of the Vulcanian eruptive style. Like most volcanic islands, Vulcano generates many potentially interconnected hazards, determining a potentially high risk. Here, we review the state of knowledge on its geology, eruptive activity, historical accounts, structural setting, geophysical and geochemical surveillance, and available hazard assessment, in order to have an updated picture of the state knowledge on volcanic hazard. We follow a prototypal reviewing scheme, based on three standardized steps: i) review of the volcanic system; ii) review of available eruptive and noneruptive hazard quantifications; iii) development of a conceptual interpretative model. We find that, while a rather vast literature is dedicated to the volcanic system of Vulcano and the reconstruction of past events, few quantitative hazard assessments exist. In addition, the range of natural variability considered for each hazard is potentially underestimated (e.g. limited range of considered eruption magnitude and style and of vent position), as it is the potential effect of multi-hazard impact. The developed conceptual model for the feeding system provides a synthetic picture of the present knowledge about the system, as emerged from the review. In addition, it allows for the identification of potential paths-to-eruption and provides a first order link among the main hazards. This review provides an up-to-date snapshot of existing knowledge on volcanic hazard at Vulcano on which to build future hazard quantifications as well as to support present and future decision making.

Description: Published

Description: 103186

Description: 1V. Storia eruttiva

Description: JCR Journal

Description: The Italian Government has decreed a series of progressive restrictions to delay the COVID-19 pandemic diffusion in Italy since March 10, 2020, including limitation in individual mobility and the closure of social, cultural, economic and industrial activities. Here we show the lockdown effect in Northern Italy, the COVID-19 most affected area, as revealed by noise variation at seismic stations. The reaction to lockdown was slow and not homogeneous with spots of negligible noise reduction, especially in the first week. A fresh interpretation of seismic noise variations in terms of socio-economic indicators sheds new light on the lockdown efficacy pointing to the causes of such delay: the noise reduction is significant where non strategic activities prevails, while it is small or negligible where dense population and strategic activities are present. These results are crucial for the a posteriori interpretation of the pandemic diffusion and the efficacy of differently targeted political actions.

Description: Published

Description: id 16487

Description: 7A. Geofisica per il monitoraggio ambientale

Description: JCR Journal

Description: The Sea of Galilee in northeast Israel is a freshwater lake filling a morphological depression along the Dead Sea Fault. It is located in a tectonically complex area, where a N-S main fault system intersects secondary fault patterns non-univocally interpreted by previous reconstructions. A set of multiscale geophysical, geochemical and seismological data, reprocessed or newly collected, was analysed to unravel the interplay between shallow tectonic deformations and geodynamic processes. The result is a neotectonic map highlighting major seismogenic faults in a key region at the boundary between the Africa/Sinai and Arabian plates. Most active seismogenic displacement occurs along NNW-SSE oriented transtensional faults. This results in a left-lateral bifurcation of the Dead Sea Fault forming a rhomb-shaped depression we named the Capharnaum Trough, located off-track relative to the alleged principal deformation zone. Low-magnitude (ML = 3-4) epicentres accurately located during a recent seismic sequence are aligned along this feature, whose activity, depth and regional importance is supported by geophysical and geochemical evidence. This case study, involving a multiscale/multidisciplinary approach, may serve as a reference for similar geodynamic settings in the world, where unravelling geometric and kinematic complexities is challenging but fundamental for reliable earthquake hazard assessments.

Description: Published

Description: 11932

Description: 2T. Deformazione crostale attiva

Description: JCR Journal

Description: «In senso oggettivo, il diritto è definibile come il complesso di norme giuridiche che comandano o vietano determinati comportamenti ai soggetti che ne sono destinatari», e pertanto è attraverso esso che la società pone il limite tra il lecito e l’illecito delle azioni umane e stabilisce un regime di sanzioni qualora i comportamenti violino quel limite. Il diritto è il mezzo per mettere in atto e trasformare in agire sociale una precisa visione del mondo e dei rapporti che lo determinano. Affinché l’agire sociale sia consapevole e non coatto, c’è bisogno in primis dell’educazione dei cittadini ai principi e ai valori di riferimento che sono alla base di quella visione del mondo. In tal modo la motivazione di ciò che è lecito diventa comprensibile e rafforza la consapevolezza del significato e dell’importanza di muoversi all’interno di regole e comportamenti ritenuti a vantaggio del singolo e di tutta la comunità. Educare al valore di un’azione rispettosa dell’ambiente è il solo modo per formare cittadini più responsabili, consapevoli che il gesto individuale va a inquadrarsi in una catena di azioni più ampia e articolata, e per accrescere la sensibilità e l’accettazione sociale di nuovi modelli economici più sostenibili. Il diritto sanzionatorio costituisce l’extrema ratio per salvaguardare il perimetro del lecito e in definitiva l’esistenza stessa della comunità, ma non serve a guadagnare consenso consapevole.

Description: Published

Description: 71-82

Description: 1TM. Formazione

Description: 2TM. Divulgazione Scientifica

Description: 3TM. Comunicazione

Description: Gephart and Forsyth's method has been applied to estimate stress orientations from earthquakefa ult planes olutionso f the southwesterAn lps, a regionw heret he tectonic stress regime is known to be fairly complex. Fault plane solutions have been either taken from the literature or computed using data from local and regional networks. Data refer to seismiecv entso f magnitudien the range2 .5-5.3w hicho ccurreidn the iastd ecades at depths between 0 and 25 km. Two zones with a different stress orientation have been identifiedi n the studieda rea (44.0ø-45.ø5 N, 6.5ø-8.5ø E)- the westernz one,c orresponding to the cresto f the alpine belt, where a high-dipm aximumc ompressivset ressi s found, and the easternz one (Alps chaint o Po Plain transition),c haracterizedb y an almosth orizontal E-W al and a nearly vertical as. Hypocenterso f earthquakesu sedf or stressi nversionl ie in the depthr anges0 -15 km and 5-25 km in the westerna nd easternz onesr, espectivelyT. he transitionb etweenth e two st•resdso mainsis very sharp,a nd this is alsoi ndicatedb y sp•ace distributiono f earthquakei ndividualm isfitst o the respectives tressm odels.T he findings of the present study are a good match for tectonic models which assume E-W compression derivedf rom the Adria-Europein teractiona nd producing:( 1) major thrustingp rocesses in the easterns ideo f the chaina nd (2) secondaryte nsionale ffectsa t very shallowd epth beneatht he alpineb elt crest( westernz oneo f the area studiedi n this work).

Description: Published

Description: 8171-8185

Description: 4T. Sismicità dell'Italia

Description: JCR Journal

Description: This is the dataset of the major explosions and paroxysms record at Stromboli from 1879 to 1960, as reconstructed through a detailed review of scientific literature of the last ca. 140 years. The catalog includes the calendar date and phenomena descriptions for 120 explosive events, of which 32 were paroxysms. We summarized the event information content in five columns – (i) noise and earthquakes, (ii) ash plume, (iii) large ejecta, (iv) PDC and tsunami, (v) lava flows. Where possible, the extracts contained the description of any volcanic activity at least one month before the eruption and one month after. The catalog also includes a sequence of extracts from the original literature sources that helped us in the complex characterization of the less recent events. In our analysis, we mostly relied on the detailed characterization of major explosions and paroxysms in Rosi et al. 2013 that provided quantitative constraints on total duration, fallout volume, mass discharge rate, ballistic size, ballistic range and column height of ordinary activity, major explosions, and paroxysms. In several cases, we had to carefully evaluate the original description of the phenomena, due to insufficient quantitative information in the scientific literature. In particular, we considered the area affected by large ballistic projectiles as the discriminant factor to distinguish between ordinary activity, major explosions and paroxysms. This area is limited to the Crater Terrace in case of ordinary activity, to the summit area of the volcano and Sciara del Fuoco during major explosions, and can extend down to low elevations along large part of the island, and sometimes beyond the shoreline, during the paroxysms (Barberi et al., 1993). We also considered several other factors, including the height of the plume, the amount of ash and scoria fallout, the occurrence and strength of any associated shock wave. The occurrence of PDC and/or tsunami associated with the violent explosive activity was assumed as a marker for a paroxysm too(Rosi et al., 2013). The determination of the hour and minute of the explosion in the historical documents usually distinguishes the most violent phenomena. Whilst identifying the paroxysms was relatively straightforward, several possible major explosions were not clearly distinguishable from particularly violent episodes of the ordinary Strombolian activity. Thus, our historical record includes the quantification of the main sources of uncertainty, i.e. the possibility of major explosions of uncertain characterization because of insufficient information. We thus categorized as uncertain 45 major explosions.

Description: INGV

Description: Published

Description: 1V. Storia eruttiva

Description: We propose the energy-dependent magnitude-frequency (EDMF) model as an alternative of the classical (tapered or not) Gutenberg-Richter (G-R) law for the magnitude of seismic events, the most widely used in earthquake forecasting and seismic hazard applications. The model we present is a modification of the Kagan’s tapered G-R law: the corner moment parameter is assumed to be an energy-varying function, changing with respect to the size of the area under analysis, and to the seismic history occurred in the area itself. The basic rationale behind our model rests in the criticism to the applicability of the G-R law on small space-time windows, many times raised in the literature and already tackled for some operational forecasting projects, as for example in the UCERF3 for California. The EDMF model is built in such a way to decrease the probability of large events in a small area where a strong shock has just occurred and to reobtain the classical G-R when enlarging the analyzed region.We do not account for a parental connection between events, neither for an order relation between their magnitudes.We simply condition to the elastic energy available in the area considered, which depends on the time elapsed since the last strong event that is assumed to have resetted the energy available, as well as on the length of the longest fault included in the area. The applicability of the proposed EDMF model is shown for the Californian seismic catalog; we obtain results that support the validity of the EDMF model and its potential to improve large earthquake forecasting at different time scales.

Description: Unpublished

Description: Hakone, Japan

Description: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica

Description: Understanding the processes occurring inside a landfill is important for improving the treatment of landfills. Irrigation and recirculation of leachate are widely used in landfill treatments. Increasing the efficiency of such treatments requires a detailed understanding of the flow inside the landfill. The flow depends largely on the heterogeneous distribution of density. It is, therefore, of great practical interest to determine the density distribution affecting the flow paths inside a landfill. Studies in the past have characterized landfill sites but have not led to high-resolution, detailed quantitative results. We performed an S-wave reflection survey, multichannel analysis of surface waves (MASW), and electrical resistivity survey to investigate the possibility of delineating the heterogeneity distribution in the body of a landfill. We found that the high-resolution S-wave reflection method offers the desired resolution. However, in the case of a very heterogeneous landfill and a high noise level, the processing of high-resolution, shallow reflection data required special care. In comparison, MASW gave the general trend of the changes inside the landfill, whereas the electrical resistivity (ER) survey provides useful clues for interpretation of seismic reflection data. We found that it is possible to localize fine-scale heterogeneities in the landfill using the S-wave reflection method using a high-frequency vibratory source. Using empirical relations specific to landfill sites, we then estimated the density distribution inside the landfill, along with the associated uncertainty considering different methods. The final interpretation was guided by supplementary information provided by MASW and ER tomography.

Description: Published

Description: EN13–EN25

Description: 7A. Geofisica per il monitoraggio ambientale

Description: JCR Journal

Description: Reliable automatic procedure for locating earthquake in quasi-real time is strongly needed for seismic warning system, earthquake preparedness, and producing shaking maps. The reliability of an automatic location algorithm is influenced by several factors such as errors in picking seismic phases, network geometry, and velocity model uncertainties. The main purpose of this work is to investigate the performances of different automatic procedures to choose the most suitable one to be applied for the quasi-real-time earthquake locations in northwestern Italy. The reliability of two automatic-picking algorithms (one based on the Characteristic Function (CF) analysis, CF picker, and the other one based on the Akaike Information Criterion (AIC), AIC picker) and two location methods (“Hypoellipse” and “NonLinLoc” codes) is analysed by comparing the automatically determined hypocentral coordinates with reference ones. Reference locations are computed by the “Hypoellipse” code considering manually revised data and tested using quarry blasts. The comparison is made on a dataset composed by 575 seismic events for the period 2000–2007 as recorded by the Regional Seismic network of Northwestern Italy. For P phases, similar results, in terms of both amount of detected picks and magnitude of travel time differences with respect to manual picks, are obtained applying the AIC and the CF picker; on the contrary, for S phases, the AIC picker seems to provide a significant greater number of readings than the CF picker. Furthermore, the “NonLin- Loc” software (applied to a 3D velocity model) is proved to be more reliable than the “Hypoellipse” code (applied to layered 1D velocity models), leading to more reliable automatic locations also when outliers (wrong picks) are present.

Description: Published

Description: 393–411

Description: 8T. Sismologia in tempo reale

Description: JCR Journal

Description: We develop a mathematical model describing dyke propagation in proximity of an elastic discontinuity of the embedding medium. The dyke is modelled as a fluid-filled crack in plane strain configuration employing the boundary element method. The pressure gradient along the crack is assumed proportional to the difference between the densities of the host rock and the fluid. Mass conservation is imposed during propagation and fluid compressibility is taken into account. The path followed by the crack is found by maximizing the total energy release, given by the sum of the elastic and gravitational contributions. The mathematical simulations provide a sort of ‘refraction phenomenon’, that is a sudden change in the direction of propagation when the crack crosses the boundary separating different rigidities: if the dyke enters a softer medium, its path deviates towards the vertical, if the dyke enters a harder medium its path deviates away from the vertical and may even become arrested as a horizontal sill along the interface, if the rigidity contrast is large. Gravitational energy plays a major role during propagation; in particular, in proximity of layer boundaries, this role is enhanced by the shift of the centre of mass due to changes of dyke shape. Mathematical results were validated by laboratory experiments performed injecting tilted air-filled cracks through gelatin layers with different rigidities.

Description: Published

Description: 1107-1123

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: JCR Journal

Description: It has been posited that the 1975–1984 Krafla rifting episode in northern Iceland was responsible for a significant drop in the rate of earthquakes along the Húsavík-Flatey Fault (HFF), a transform fault that had previously been the source of several magnitude 6–7 earthquakes. This compelling case of the existence of a stress shadow has never been studied in detail, and the implications of such a stress shadow remain an open question. According to rate-state models, intense stress shadows cause tens of years of low seismicity rate followed by a faster recovery phase of rate increase. Here, we compare the long-term predictions from a Coulomb stress model of the rifting episode with seismological observations from the SIL catalog (1995–2011) in northern Iceland. In the analyzed time frame, we find that the rift-induced stress shadow coincides with the eastern half of the fault where the observed seismicity rates are found to be significantly lower than expected, given the historical earthquake activity there. We also find that the seismicity rates on the central part of the HFF increased significantly in the last 17 years, with the seismicity progressively recovering from west to east. Our observations confirm that rate-state theory successfully describes the long-term seismic rate variation during the reloading phase of a fault invested by a negative Coulomb stress. Coincident with this recovery, we find that the b-value of the frequency-magnitude distribution changed significantly over time. We conclude that the rift-induced stress shadow not only decreased the seismic rate on the eastern part of the HFF but also temporarily modified how the system releases seismic energy, with more large magnitude events in proportion to small ones. This behavior is currently being overturned, as rift-induced locking is now being compensated by tectonic forcing.

Description: Published

Description: 1109-1121

Description: 5V. Processi eruttivi e post-eruttivi

Description: JCR Journal

Description: Dikes and sills are the moving building blocks of the plumbing system of volcanoes and play a fundamental role in the accretionary processes of the crust. They nucleate, propagate, halt, resume propagation, and sometimes change trajectory with drastic implications for the outcome of eruptions (Sigmundsson et al., 2010). Their dynamics is still poorly understood, in particular when different external influencing factors are interacting. Here we apply a boundary element model to study dike and sill formation, propagation and arrest in different scenarios. We model dikes as finite batches of compressible fluid magma, propagating quasi-statically in an elastic medium, and calculate their trajectories by maximising the energy release of the magma-rock system. We consider dike propagation in presence of density layering, of density plus rigidity layering, of a weakly welded interface between layers, under the action of an external stress field (of tectonic or topographic origin). Our simulations predict sill formation in several situations: i) when a horizontal weak interface is met by a propagating dike; ii) when a sufficiently high compressive tectonic environment is experienced by the ascending dike and iii) in case a dike, starting below a volcanic edifice, propagates away from the topographic load with a low dip angle. We find that dikes halt and stack when they become negatively buoyant and when they propagate with low overpressure at their upper tip toward a topographic load. Neutral buoyancy by itself cannot induce dikes to turn into sills, as previously suggested.

Description: Published

Description: 39-50

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: JCR Journal

Description: The sources and sinks of stratospheric reactive nitrogen (NOy) in the Antarctic are known only qualitatively, because of the very few measurements of NOy available in this region. As a result, the effects of stratospheric NOy short- and long-term changes on the stratospheric concentration of ozone, water vapor, and other climate-forcing agents are still uncertain. To better understand the annual cycle of polar stratospheric NOy, we estimate its concentration in the Antarctic stratosphere during part of 1993 and throughout 1995. These estimates are obtained at seven potential temperature levels, extending from 18 to 30 km of altitude, and are associated with ground-based measurements of another tracer, N2O, in order to produce NOy-N2O correlation curves that can provide insights on nitrogen sources and sinks. To estimate NOy mixing ratios, we use ground-based and satellite measurements of major NOy constituents, connected by using air parcel trajectories and supplemented by model calculations of minor contributing species for which no suitable measurements exist. All the available NOy-N2O correlation points are averaged over three representative seasonal time periods in 1993 and six periods in 1995. Results show very similar correlation curves during the late summer and the fall of 1995, and again during the early spring 1993 compared with the early and late winter of 1995, although there are large seasonal changes due to transport and to condensation of NOy onto polar stratospheric clouds. We calculate a loss from the latter process of N = (6.3 ± 2.6) 107 kg of stratospheric nitrogen in the southern polar vortex during 1995.We also compare our correlation curves with those obtained in the Antarctic stratosphere during the Atmospheric Trace Molecule Spectroscopy mission ATMOS/ATLAS-3 in November 1994, finding important similarities but also critical differences that suggest that extravortex air is generally not an adequate representation of prewinter inner vortex conditions. Calculations of NOy winter removal in the Antarctic stratosphere which have used extra-vortex measurements as a surrogate for prewinter conditions may thus have underestimated true NOy removal. Our prewinter NOy estimates in the vortex core match values obtained by atmospheric models that incorporate upper atmospheric sources of NOy, supporting the belief that such sources have a significant effect on polar stratospheric NOy.

Description: Published

Description: 4428

Description: 5A. Ricerche polari e paleoclima

Description: JCR Journal

Description: We describe a new method for the reconstruction (or forecast) of probabilities that distal geographic locations were inundated by a giant pyroclastic density current (PDC) in terms of the flow mass and related uncertainties. Using appropriate model input uncertainty distributions, derived from expert judgements using the equal weights combination rule, we can estimate the mass amount needed to reach a particular distal locality at any given confidence level and compare this with ambiguous or inexact field data. Our analysis relies on different versions of the Huppert and Simpson (1980) integral formulation of axisymmetric gravity-driven particle currents. We focus on models which possess analytical solutions, enabling us to utilize a very fast functional approach for enumerating results and uncertainties. In particular, we adapt the ‘energy conoid’ approach to generate inundation maps along radial directions, based on comparison of the mass-dependent kinetic energy of the flow with the potential energy control by topography in the direction of flow at distal ranges. We focus on two different models: (i) Model 1 assumes the entire amount of solid material originates from a prescribed height above the volcano and flows as a granular current slowed down by constant friction; (ii) Model 2 is a multi-phase formulation and includes, in addition to suspended particles, interstitial gas thermally buoyant with respect to surrounding cold air. In the latter case, the flow stops propagating when the solid fraction becomes less than a critical value, and there is lift-off of the remaining mixture of gas and small particulates. Our model parameters can be further constrained where there is reliable field data or with information from analogue eruptions. Finally, we used a Bayes Belief Network related to each inversion model to evaluate probabilistically the uncertainties on the mass required, estimating correlation coefficients between the input variables and the calculated mass. For any major magnitude ignimbrite PDC scenario, our method provides a rational basis for assessing the probability of flow inundation at critical geographic locations within distal areas when there is major uncertainty about the actual or predicted extent of flow runout. Example case histories are illustrated.

Description: Published

Description: San Francisco (CA)

Description: 6V. Pericolosità vulcanica e contributi alla stima del rischio

Description: In this study we present a new effort to improve the uncertainty quantification (UQ) of pyroclastic density current dynamics in the Campi Flegrei caldera, thanks to the implementation of a new 2D depth-averaged granular flow model in the Monte Carlo simulation of keycontrolling variables. Campi Flegrei caldera is an active and densely populated volcanic area in the urban neighborhood of Napoli, characterized by the presence of many dispersed cones and craters, and by a caldera wall more than one hundred meters high, towards East. Basic mapping of pyroclastic density currents (PDC) hazard at Campi Flegrei has been already reported in previous studies: some related to field reconstruction and numerical modeling of specific past eruptions or individual scenarios, while others endeavored to produce specific or integrated PDC hazard maps in which the variability of important parameters of the volcanic system was explicitly accounted for. In particular, [4, 2] obtained quantitative estimates of probabilistic PDC hazard, based on the implementation of a simplified kinematic invasion model able to represent main topographic effects. This model, called box model, was extensively run thousands of times in the Monte Carlo simulation varying vent location, eruptive scale, and time frequency of the future activity. In this study we build our effort upon the previous research started in [7, 5], and utilize the physical modeling approach of [6], with the effcient numerical solution of depth-averaged equations for the flow mass and momentum, considering the effects of basal and internal, velocity dependent, friction forces. The model describes the gas-particle mixture as a homogeneous flow, assuming a mechanism of particle deposition consistent with that previously implemented in the box model. UQ is performed by assuming three different components in the input space: (i) rheology parameters, (ii)volume scale, (iii) source location. Our statistical analysis focuses on the first two components, considering a relatively small number of source locations or an uncertain source location inside a subregion of the caldera. This is a first step before the exploration of the full spatial variability of the source location. The statistical inversion of box model equations, varying the vent location (x; y) and the value of inundated area A, can provide us with initial probability estimates for the volume scale of the PDC flow, either in terms of runout distance or volume extent of the multiphase mixture. Our depth averaged model relies on these estimates for setting up the volume scale of past flows. The calibration of rheology parameters is performed according to that. Thus, the rheology and volume components of the input space are conjointly explored by means of Latin Hypercube sampling, attempting a hierarchical conditioning on feasible inputs and plausible outputs [3]. [1] A. Bevilacqua, F. Flandoli, A. Neri, R. Isaia, S. Vitale, “Temporal models for the episodic volcanism of Campi Flegrei caldera (Italy) with uncertainty quantification," Journal of Geophysical Research: Solid Earth 121, 11 (2016). [2] A. Bevilacqua, A. Neri, M. Bisson, T. Esposti Ongaro, F. Flandoli, R. Isaia, M. Rosi, S. Vitale, “The e ects of vent location, event scale, and time forecasts on pyroclastic density current hazard maps at Campi Flegrei caldera (Italy)," Frontiers in Earth Science 5, 72 (2017). [3] A. Bevilacqua, A.K. Patra, M.I. Bursik, E.B. Pitman, J.L. Macías, R. Saucedo, D. Hyman, “Probabilistic forecasting of plausible debris flows from Nevado de Colima (Mexico) using data from the Atenquique debris flow, 1955," Natural Hazards Earth System Science 19, 791-820 (2019). [4] A. Neri, A. Bevilacqua, T. Esposti Ongaro, R. Isaia, W.P. Aspinall, M. Bisson, F. Flandoli et al., “Quantifying volcanic hazard at Campi Flegrei caldera (Italy) with uncertainty assessment: 2. Pyroclastic density current invasion maps," Journal of Geophysical Research: Solid Earth 120, 2330-2349 (2015). [5] T. Esposti Ongaro, S. Orsucci and F. Cornolti, “A fast, calibrated model for pyroclastic density currents kinematics and hazard," Journal of Volcanology and Geothermal Research 327, 257 - 272 (2016). [6] M. de’ Michieli Vitturi, T. Esposti Ongaro, G. Lari, and A. Aravena, “IMEXSfloW2D 1.0: a depth-averaged numerical flow model for pyroclastic avalanches," Geoscientific Model Development, 12, 581-595 (2019). [7] M. Todesco, A. Neri, T. Esposti Ongaro, P. Papale, and M. Rosi, “Pyroclastic flow dynamics and hazard in a caldera setting: Application to Phlegrean Fields (Italy)," Geochemistry Geophysics Geosystems, 7, Q11003 (2006).

Description: Published

Description: Pisa

Description: 5V. Processi eruttivi e post-eruttivi

Description: In December 2018, Mount Etna (Italy) experienced a period of increased eruptive activity that culminated in a fissure eruption on the southeast flank. After the onset of the flank eruption, the peak frequency of the summit infrasound signals decreased while resonance increased. We invert infrasound observations for crater geometry and show that crater depth and radius increased during the eruption, which suggests that the flank eruption drained magma from the summit and that eruptive activity led to erosion of the crater wall. By inverting the entire infrasound amplitude spectra rather than just the peak frequency, we are able to place additional constraints on the crater geometry and invert for, rather than assume, the crater shape. This work illustrates how harmonic infrasound observations can be used to obtain hightemporal‐ resolution information about crater geometry and can place constraints on complex processes occurring in the inaccessible crater region during eruptive activity.

Description: Published

Description: e2020GL088077

Description: 2V. Struttura e sistema di alimentazione dei vulcani

Description: JCR Journal

Description: The geomagnetic field is subject to possible reversals or excursions of polarity during its temporal evolution. Considering that: (a) in the last 83 million yr the typical average time between one reversal and the next (the so-called chron) is around 400 000 yr, (b) the last reversal occurred around 780 000 yr ago, (c) more excursions (rapid changes in polarity) can occur within the same chron and (d) the geomagnetic field dipole is currently decreasing, a possible imminent geomagnetic reversal or excursion would not be completely unexpected. In that case, such a phenomenon would represent one of the very few natural hazards that are really global. The South Atlantic Anomaly (SAA) is a great depression of the geomagnetic field strength at the Earth’s surface, caused by a reverse magnetic flux in the terrestrial outer core. In analogy with critical point phenomena characterized by some cumulative quantity, we fit the surface extent of this anomaly over the last 400 yr with power law or logarithmic functions in reverse time, also decorated by logperiodic oscillations, whose final singularity (a critical point tc) reveals a great change in the near future (2034±3 yr), when the SAA area reaches almost a hemisphere. An interesting aspect that has recently been found is the possible direct connection between the SAA and the global mean sea level (GSL). That the GSL is somehow connected with SAA is also confirmed by the similar result when an analogous critical-like fit is performed over GSL: the corresponding critical point (2033±11 yr) agrees, within the estimated errors, with the value found for the SAA. From this result, we point out the intriguing conjecture that tc would be the time of no return, after which the geomagnetic field could fall into an irreversible process of a global geomagnetic transition that could be a reversal or excursion of polarity.

Description: Published

Description: 3395-3403

Description: 1A. Geomagnetismo e Paleomagnetismo

Description: JCR Journal

Description: open

Description: The role of diffuse photospheric magnetic elements in the energy budget of the upper layers of the Sun’s atmosphere has been the recent subject of many studies. This was made possible by the availability of high temporal and spatial resolution observations of the solar photosphere, allowing large numbers of magnetic elements to be tracked to study their dynamics. In this work we exploit a long temporal series of seeing-free magnetograms of the solar photosphere to study the effect of the turbulent convection on the excitation of kink oscillations in magnetic elements. We make use of the empirical mode decomposition technique in order to study the transverse oscillations of several magnetic flux tubes. This technique permits analysis of non-stationary time series like those associated to the horizontal velocities of these flux tubes, which are continuously advected and dispersed by granular flows. Our primary findings reveal the excitation of low frequency modes of kink oscillations, which are subharmonics of a fundamental mode with a 7.6 ± 0.2 min periodicity. These results constitute observational proof of the excitation of kink waves by the buffeting of the convection cells in the solar photosphere, and they are discussed in light of their possible role in the energy budget of the upper Sun’s atmosphere.

Description: Published

Description: A102

Description: 1A. Geomagnetismo e Paleomagnetismo

Description: JCR Journal

Description: restricted

Description: In this paper we present a probabilistic hazard assessment for tephra fallout at Mt. Etna (Italy) associated with both short- and long-lived eruptions. Eruptive scenarios and eruption source parameters were defined based on the geological record, while an advection–diffusion–sedimentation model was used to capture the variation in wind speed and direction with time after calibration with the field data. Two different types of eruptions were considered in our analysis: eruptions associated with strong short-lived plumes and eruptions associated with weak long-lived plumes. Our probabilistic approach was based on one eruption scenario for both types and on an eruption range scenario for eruptions producing weak long-lived plumes. Due to the prevailing wind direction, the eastern flanks are the most affected by tephra deposition, with the 122 BC Plinian and 2002–2003 eruptions showing the highest impact both on infrastructures and agriculture.

Description: Published

Description: 3221– 3233

Description: 3V. Dinamiche e scenari eruttivi

Description: JCR Journal

Description: open

Description: A sequence of thousands of small to moderate earthquakes has been occurring since spring 2010 in the Pollino Mountains area, southern Italy, where a seismic gap was previously hypothesized by paleoseismological evidence associated with the lack of major earthquakes in historical catalogs.

Description: Published

Description: 955-962

Description: 2T. Tettonica attiva

Description: JCR Journal

Description: restricted

Description: We show the preliminary seismic monitoring of a historical church in L’Aquila (central Italy), which was strongly damaged by the 2009 seismic sequence. This structure, S. Maria del Suffragio church, suffered the collapse of a great part of the dome during the April 6th 2009 Mw 6.1 earthquake. In this paper, recordings of ambient noise and local earthquakes have been analyzed. The seismic data were recorded by means of a dynamic monitoring system (19 mono-directional and 3 tri-directional piezoelectric accelerometers) and of two velocimeters, with all the instruments installed into the church. The aim of this re- search is the evaluation of the performance of the accelerometers of the monitoring system in case of low-amplitude vibrations. Simple techniques of analysis commonly employed in the seismic characterization of buildings have been applied. The reliability of the in-situ data was evaluated and the main modal parameters (natural frequencies and damping ratio) of the church were presented

Description: Published

Description: S0654

Description: 1IT. Reti di monitoraggio e Osservazioni

Description: JCR Journal

Description: restricted