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  • 04.08. Volcanology  (28)
  • 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous  (6)
  • Wave propagation
  • Elsevier B.V.  (14)
  • Wiley-AGU  (14)
  • Wiley  (9)
  • Cell Press
  • International Union of Crystallography (IUCr)
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  • 1
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    Supervised learning (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-01
    Beschreibung: In supervised classification, we search criteria allowing us to decide whether a sample belongs to a certain class of patterns. The identification of such decision functions is based on examples where we know a priori to which class they belong. The distinction of seismic signals, produced from earthquakes and nuclear explosions, is a classical problem of discrimination using classification with supervision. We move on from observed data—signals originating from known earthquakes and nuclear tests—and search for criteria on how to assign a class to a signal of unknown origin. We begin with Principal Component Analysis (PCA) and Fisher's Linear Discriminant Analysis (FLDA), identifying a linear element separating groups at best. PCA, FLDA, and likelihood-based approaches make use of statistical properties of the groups. Considering only the number of misclassified samples as a cost, we may prefer alternatives, such as the Multilayer Perceptrons (MLPs). The Support Vector Machines (SVMs) use a modified cost function, combining the criterion of the minimum number of misclassified samples with a request of separating the hulls of the groups with a margin as wide as possible. Both SVMs and MLPs overcome the limits of linear discrimination. A famous example for the advantages of the two techniques is the eXclusive OR (XOR) problem, where we wish to form classes of objects having the same parity—even, e.g., (0,0), (1,1) or odd, e.g., (0,1), (1,0). MLPs and SVMs offer effective methods for the identification of nonlinear decision functions, allowing us to resolve classification problems of any complexity provided the data set used during earning is sufficiently large. In Hidden Markov Models (HMMs), we consider observations where their meaning depends on their context. Observations form a causal chain generated by a hidden process. In Bayesian Networks (BNs) we represent conditional (in)dependencies between a set of random variables by a graphical model. In both HMMs and BNs, we aim at identifying models and parameters that explain observations with a highest possible degree of probability.
    Beschreibung: Published
    Beschreibung: 33-85
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; supervised learning ; Support Vector Machines ; Multilayer Perceptrons ; Hidden Markov Models ; Bayesian Networks ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 2
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    Patterns, objects, and features (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-01
    Beschreibung: Patterns and objects are described by a variety of characteristics, namely features and feature vectors. Features can be numerical, ordinal, and categorical. Patterns can be made up of a number of objects, such as in speech processing. In geophysics, numerical features are the most common ones and we focus on those. The choice of appropriate features requires a priori reasoning about the physical relation between patterns and features. We present strategies for feature identification and procedures suitable for pattern recognition. In time series analysis and image processing, the direct use of raw data is not feasible. Procedures of feature extraction, based on locally encountered characteristics of the data, are applied. Here we present the problem of delineating segments of interest in time series and textures in image processing. In transformations, we “translate” our raw data to a form suitable for learning. In Principal Component Analysis, we rotate the original features to a system of uncorrelated variables, limiting redundancy. Independent Component Analysis follows a similar strategy, transforming our data into variables independent of each other. Fourier transform and wavelet transform are based on the representation of the original data as a series of basis functions—sines and cosines or finite-length wavelets. Redundancy reduction is achieved considering the contributions of the single basis functions. Even though a large number of features help to solve a classification problem, feature vectors with high dimensions pose severe problems. Besides the computational burden, we encounter problems known under the term “curse of dimensionality.” The curse of dimensionality entails the necessity of feature selection and reduction, which includes a priori considerations as well as redundancy reduction. The significance of features may be evaluated with tests, such as Student’s t or Hotelling's T2, and, in more complex problems, with cross-validation methods.
    Beschreibung: Published
    Beschreibung: 3-13
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; objects ; features ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 3
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    On the Propagation Path of Magma‐Filled Dikes and Hydrofractures: The Competition Between External Stress, Internal Pressure, and Crack Length (2019)
    Wiley
    Details
    Publikationsdatum: 2021-03-09
    Beschreibung: Mixed‐mode fluid‐filled cracks represent a common means of fluid transport within the Earth's crust. They often show complex propagation paths which may be due to interaction with crustal heterogeneities or heterogeneous crustal stress. Previous experimental and numerical studies focus on the interplay between fluid over-pressure and external stress but neglect the effect of other crack parameters. In this study, we address the role of crack length on the propagation paths in the presence of an external heterogeneous stress field. We make use of numerical simulations of magmatic dike and hydrofracture propagation, carried out using a two‐dimensional boundary element model, and analogue experiments of air‐filled crack propagation into a transparent gelatin block. We use a 3‐D finite element model to compute the stress field acting within the gelatin block and perform a quantitative comparison between 2‐D numerical simulations and experiments. We show that, given the same ratio between external stress and fluid pressure, longer fluid‐filled cracks are less sensitive to the background stress, and we quantify this effect on fluid‐filled crack paths. Combining the magnitude of the external stress, the fluid pressure, and the crack length, we define a new parameter, which characterizes two end member scenarios for the propagation path of a fluid‐filled fracture. Our results have important implications for volcanological studies which aim to address the problem of complex trajectories of magmatic dikes (i.e., to forecast scenarios of new vents opening at volcanoes) but also have implications for studies that address the growth and propagation of natural and induced hydrofractures.
    Beschreibung: Published
    Beschreibung: 2064–2081
    Beschreibung: 2V. Struttura e sistema di alimentazione dei vulcani
    Beschreibung: JCR Journal
    Schlagwort(e): Magmatic dykes ; hydrofractures ; Numerical symulations ; Analogue experiments ; 04.08. Volcanology ; 05.05. Mathematical geophysics
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 4
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    3D multi-source model of elastic volcanic ground deformation (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-01-07
    Beschreibung: https://www.sciencedirect.com/science/article/abs/pii/S0012821X20303897
    Beschreibung: Published
    Beschreibung: 116445
    Beschreibung: 2V. Struttura e sistema di alimentazione dei vulcani
    Beschreibung: JCR Journal
    Schlagwort(e): 3D model ; multi-source ; elastic medium ; ground deformation ; 04. Solid Earth ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 5
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    The growth and erosion of cinder cones in Guatemala and El Salvador: Models and statistics (2011)
    Elsevier B.V.
    Details
    Publikationsdatum: 2020-11-18
    Beschreibung: Morphologic data for 147 cinder cones in southern Guatemala andwestern El Salvador are comparedwith data from the San Francisco volcanic field, Arizona (USA), Cima volcanic field, California (USA), Michoácan–Guanajuato volcanic field, Mexico, and the Lamongan volcanic field, East Java. The Guatemala cones have an average height of 110+/-50 m, an average basal diameter of 660+/-230 m and an average top diameter of 180+/-150 m. The generalmorphology of these cones can be described by their average cone angle of slope (24+/-7), average heightto- radius ratio (0.33+/-0.09) and their flatness (0.24+/-0.18). Although the mean values for the Guatemalan cones are similar to those for other volcanic fields (e.g., San Francisco volcanic field, Arizona; Cima volcanic field, California; Michoácan–Guanajuato volcanic field, Mexico; and Lamongan volcanic field, East Java), the range of morphologies encompasses almost all of those observed worldwide for cinder cones. Three new 40Ar/39Ar age dates are combined with 19 previously published dates for cones in Guatemala and El Salvador. There is no indication that the morphologies of these cones have changed over the last 500–1000 ka. Furthermore, a re-analysis of published data for other volcanic fields suggests that only in the Cima volcanic field (of those studied) is there clear evidence of degradation with age. Preliminary results of a numerical model of cinder cone growth are used to show that the range of morphologies observed in the Guatemalan cinder cones could all be primary, that is, due to processes occurring at the time of eruption.
    Beschreibung: Support for Walker was provided by NSF MARGINS grant OCE- 0405666.
    Beschreibung: Published
    Beschreibung: 39-52
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: JCR Journal
    Beschreibung: open
    Schlagwort(e): cinder cones ; morphology ; age dating ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.03. Geomorphology ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous ; 05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 6
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    A posteriori analyses—advantages and pitfalls of pattern recognition techniques (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-01
    Beschreibung: In this chapter, we deal with a posterior analysis of supervised and unsupervised learning techniques. Concerning supervised learning, we discuss methods of cross-validation and assessment of uncertainty of tests by means of the “Receiver Operation Curve” and the “Kappa-Statistics.” We show the importance of appropriate target information. Furthermore, features are critical; when they are not properly chosen, they fail to describe objects in a unique way. A critical attitude is mandatory to validate the success of an application. A high score of success does not automatically mean that a method is truly effective. At the same time, users should not despair when the desired success is not achieved. A posteriori analysis on the reasons for an apparent failure may provide useful insights into the problem. Targets may not be appropriately defined, features can be inadequate, etc. Problems can be often fixed by adjusting a few choices; sometimes a change of strategy may be necessary to improve results. In unsupervised learning, we ask whether the structures revealed in the data are meaningful. Cluster analysis offers rules giving formal answers to this question; however, such rules are not generally applicable. In some cases, a heuristic approach may be necessary.
    Beschreibung: Published
    Beschreibung: 237-259
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; a posteriori analysis ; supervised learning ; unsupervised learning ; cross validation ; assessment of uncertainty ; Receiver Operation Curve ; Kappa-Statistics ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 7
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    Unsupervised learning (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-01
    Beschreibung: Unsupervised learning is based on the definition of an appropriate metrics defining the similarity of patterns. On the basis of the metrics, we form groups or clusters of patterns following various strategies. In partitioning cluster analysis, we form disjoint clusters. Being faced with data, where clusters still exhibit heterogeneities or subclusters, we may adopt the strategy of hierarchical clustering, which leads to the generation of the so-called dendrograms. In the partitioning strategy, we choose a priori the number of clusters we wish to form, whereas in the hierarchical strategy, the number of clusters depends on the resolution we want to have. Density-based clustering considers local structures of a data set. We consider a unit volume in our data space and derive the density of samples within this volume. Moving toward neighboring volumes, we verify whether the number of samples has dropped below a threshold. If this is the case, we identify a heterogeneity, otherwise we join the neighboring volumes to a common cluster. Self-Organizing Maps (SOMs) provide a way of representing multidimensional data in much lower dimensional spaces than the original data set. The process of reducing the dimensionality of vectors is essentially a data compression technique known as vector quantization. The SOM technique creates a network that stores information in a way that it maintains the topological relationships within the patterns of the data set. Each node of the network represents a number of patterns. Assigning a color code to the nodes, the representation of pattern characteristics with high-dimensional feature vectors becomes extremely effective.
    Beschreibung: Published
    Beschreibung: 87-124
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; unsupervised learning ; cluster analysis ; Density-based clustering ; Self-Organizing Maps ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 8
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    Applications with unsupervised learning (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-01
    Beschreibung: This chapter demonstrates how Unsupervised Learning can be applied in Geophysics. It starts with an example of clustering seismic spectra obtained on Stromboli volcano. K-means clustering as well as clustering using the Adaptive Criterion are applied. The latter criterion is preferred as it better matches the statistical characteristics of the data. Clusters show close relation to the state of volcanic activity. Density based clustering reveals groups whose hulls can be of irregular shape. This makes the method attractive, among others, for the identification of structural elements in geology, which often do not have a simple geometry. An example application is discussed considering the distribution of earthquake locations on Mt Etna, which clearly evidence structures already identified by other, independent evidences. Using SOM we aim at data reduction and effective graphical visualization. In an example for climate data we demonstrate the application of SOM for zoning purposes. Besides, the temporal evolution of spectral seismic data recorded on Mt Etna can be effectively monitored using SOM. We further illustrate the use of SOM for directional data, which can be handled best using a toroidal sheet geometry. We discuss this using a data set of seismic moment tensors of Mediterranean earthquakes.
    Beschreibung: Published
    Beschreibung: 189-234
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; unsupervised learning ; Density based clustering ; Stromboli ; earthquakes ; volcanic activity ; structural data ; seismic moment tensors ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 9
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    Software manuals (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-01
    Beschreibung: In this chapter, we present scripts and programs that accompany this book. Five MATLAB scripts regard simple examples related to supervised learning, that is, linear discrimination, the perceptron, support vector machines, and hidden Markov models. Seven scripts are devoted to unsupervised learning, such as K-means and fuzzy clustering, agglomerative clustering, density-based clustering, and clustering of patterns where features are correlated. These scripts provide a starting point for the reader, who can adjust and modify the codes with respect to proper needs. Besides, we provide sources and executables of programs that can be readily applied to larger and more complex datasets. These programs regard supervised learning using multilayerperceptron and support vector machines. KKAnalysis is a toolbox for unsupervised learning and offers various options of clustering and the use of self-organizing maps. The programs offer graphical user interfaces (GUI) to facilitate their use and create both graphical and alphanumeric output that can be used in further processing steps. The programs come along with real-world datasets that are also discussed in the example applications presented in various chapters of the book. Other propaedeutic material can be found in a folder called “miscellaneous.”
    Beschreibung: Published
    Beschreibung: 261-313
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; software manuals ; MATLAB scripts ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 10
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    Development and decline of the ancient Harbor of Neapolis (2018)
    Wiley
    Details
    Publikationsdatum: 2021-07-14
    Beschreibung: Archaeological exavations,undertaken since 2004 for the construction of the new Naples subway
    Beschreibung: Published
    Beschreibung: 542-557
    Beschreibung: 1V. Storia eruttiva
    Beschreibung: JCR Journal
    Schlagwort(e): A.D.79 eruption ; compositional data analysis ; geoarchaeology ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 11
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    Applications of supervised learning (2021)
    Elsevier B.V.
    Details
    Publikationsdatum: 2021-02-15
    Beschreibung: This chapter presents applications of supervised learning in various geophysical disciplines, being them seismology, geodesy, magnetism, and others. For all examples, we provide a brief introduction to the geophysical background. Practical aspects, such as normalization issues and feature selection, are discussed. A posteriori considerations shed light on the geophysical problem, such as the importance of model parameters in regression, the possible nonuniqueness in inversion, and flaws in the definition of targets. We demonstrate multilayer perceptrons (MLPs) as classifiers of seismic waveforms. Besides, we show how the use of MLP is straightforward in the context of inversion of various kinds of data, for example, seismic, geodetic, and magnetic. Regression with MLP is applied to magnetotelluric and seismic data. Multiclass classification with support vector machine (SVM) is discussed for infrasound waveforms and volcanic rocks using geochemical characteristics. We introduce the use of SVM in the context of regression, which is formally less immediate than for MLP, but yields good results. An example deals with empirical ground motion estimation during earthquakes. In hidden Markov models and Bayesian networks one considers the interrelation between observations rather than single patterns. We show their benefits in various applications, from seismic waveform classification aimed at the forecast of volcanic unrest up to their use in tsunami early-warning systems.
    Beschreibung: Published
    Beschreibung: 127-187
    Beschreibung: 5T. Sismologia, geofisica e geologia per l'ingegneria sismica
    Schlagwort(e): pattern recognition ; supervised learning ; multilayer perceptrons ; seismic data ; magnetotelluric data ; infrasound waveforms ; volcanic rocks ; geochemical characteristics ; 04.04. Geology ; 04.06. Seismology ; 04.07. Tectonophysics ; 04.08. Volcanology ; 05.04. Instrumentation and techniques of general interest
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: book chapter
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  • 12
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    Insights into fluid circulation across the Pernicana Fault (Mt. Etna, Italy) and implications for flank instability (2010)
    Elsevier B.V.
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: We conducted geophysical–geochemical measurements on a ∼2 kmN–S profile cutting across the Pernicana Fault, one of the most active tectonic features on the NE flank of Mt. Etna. The profile passes from the unstable E flank of the volcano (to the south) to the stable N flank and significant fluctuations in electrical resistivity, self-potential, and soil gas emissions (CO2, Rn and Th) are found. The detailed multidisciplinary analysis reveals a complex interplay between the structural setting, uprising hydrothermal fluids, meteoric fluids percolating downwards, ground permeability, and surface topography. In particular, the recovered fluid circulation model highlights that the southern sector is heavily fractured and faulted, allowing the formation of convective hydrothermal cells. Although the existence of a hydrothermal system in a volcanic area does not surprise, these results have great implications in terms of flank dynamics at Mt. Etna. Indeed, the hydrothermal activity, interacting with the Pernicana Fault activity, could enhance the flank instability. Our approach should be further extended along the full extent of the boundary between the stable and unstable sectors of Etna for a better evaluation of the geohazard in this active tectonic area.
    Beschreibung: This work was partly financed by the DPC-INGV FLANK and LAVA Projects.
    Beschreibung: Published
    Beschreibung: 137–142
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 3.2. Tettonica attiva
    Beschreibung: 4.5. Studi sul degassamento naturale e sui gas petroliferi
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Pernicana Fault ; fluid circulation ; structural geology ; Etna ; magnetic ; electrical methods ; 04. Solid Earth::04.02. Exploration geophysics::04.02.99. General or miscellaneous ; 04. Solid Earth::04.02. Exploration geophysics::04.02.01. Geochemical exploration ; 04. Solid Earth::04.02. Exploration geophysics::04.02.04. Magnetic and electrical methods ; 04. Solid Earth::04.02. Exploration geophysics::04.02.05. Downhole, radioactivity, remote sensing, and other methods ; 04. Solid Earth::04.02. Exploration geophysics::04.02.07. Instruments and techniques ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.06. Rheology, friction, and structure of fault zones ; 04. Solid Earth::04.04. Geology::04.04.07. Rock geochemistry ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.04. Geology::04.04.11. Instruments and techniques ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.02. Experimental volcanism ; 04. Solid Earth::04.08. Volcanology::04.08.04. Thermodynamics ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.07. Instruments and techniques ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk ; 05. General::05.08. Risk::05.08.99. General or miscellaneous
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 13
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    Structural features of the 2007 Stromboli eruption (2009)
    Elsevier B.V.
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: On 27 February 2007, two NE–SW and NNW–SSE dike-fed effusive vents opened to the North (at 650 and 400 m above sea level, asl) of the summit craters at Stromboli, forming a fissure parallel to the inner walls of the Sciara del Fuoco (SdF) sector collapse depression. The formation of these vents was soon followed by rapid subsidence of the summit crater area. This partly obstructed the central conduit, temporarily choking the fissure and increasing the deformation of the upper part of SdF. The reactivation of the NNW–SSE vent and the opening of a new vent located at 500 m asl, fed by a second dike, released the internal pressure and surface deformation ceased. The eruption then continued again from the 400 m vent, after a summit explosion on 15 March, until ending in early April after a progressive decrease of magma output. Repeated NE–SW dike intrusions have occurred in recent years, close to the upper SE limit of the SdF. In that zone, named Bastimento, the eruptive fractures traced the discontinuities that borders the SdF, increasing the risk of triggering new sector collapse. Whereas the NE–SW trending structures lie along the regional volcanostructural trend of the Aeolian arc through Stromboli, the NNW–SSE vents are oblique to this trend and may be controlled by the anomalous stress field within the unstable flank of the SdF. Another fundamental aspect of the 2007 eruption is the collapse of the central conduit, due to the rapid and deep magma drainage linked to the opening of the 400 m vent. The intrusion of dikes and development of flank vents during the 2007 eruption could possibly have triggered catastrophic landslides and related tsunami or eruptive paroxysms, but the opening of new effusive vents released the internal pressures, diminishing the hazard.
    Beschreibung: Work funded by INGV and Dipartimento Protezione Civile, Italy.
    Beschreibung: Published
    Beschreibung: 137-144
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 3.2. Tettonica attiva
    Beschreibung: 3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): 2007 Stromboli eruption ; Dike-Fed vent ; Volcano-Tectonics ; Conduit collapse ; Flank instability ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics ; 04. Solid Earth::04.07. Tectonophysics::04.07.05. Stress ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics ; 04. Solid Earth::04.07. Tectonophysics::04.07.08. Volcanic arcs ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk ; 05. General::05.08. Risk::05.08.99. General or miscellaneous
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 14
    facet.materialart.
    Unbekannt
    Dike emplacement and flank instability at Mount Etna: Constraints from a poro-elastic-model of flank collapse (2010)
    Elsevier B.V.
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: Many volcanic edifices are subject to flank failure, usually produced by a combination of events, rather than any single process. From a dynamic point of view, the cause of collapse can be divided into factors that contribute to an increase in shear stress, and factors that contribute to the reduction in the friction coefficient μ of a potential basal failure plane. We study the potential for flank failure at Mount Etna considering a schematic section of the eastern flank, approximated by a wedge-like block. For such geometry, we perform a (steady state) limit equilibrium analysis: the resolution of the forces parallel to the possible basal failure plane allows us to determine the total force acting on the potentially unstable wedge. An estimate of the relative strength of these forces suggests that, in first approximation, the stability is controlled primarily by the balance between block weight, lithostatic load and magmatic forces. Any other force (sea load, hydrostatic uplift, and the uplift due to mechanical and thermal pore-fluid pressure) may be considered of second order. To study the model sensitivity, we let the inferred slope α of the basal surface failure vary between −10° and 10°, and consider three possible scenarios: no magma loading, magmastatic load, and magmastatic load with magma overpressure. We use error propagation to include in our analysis the uncertainties in the estimates of the mechanics and geometrical parameters controlling the block equilibrium. When there is no magma loading, the ratio between destabilizing and stabilizing forces is usually smaller than the coefficient of friction of the basal failure plane. In the absence of an initiating mechanism, and with the nominal values of the coefficient of friction μ=0.7±0.1 proposed, the representative wedge will remain stable or continue to move at constant speed. In presence of magmastatic forces, the influence of the lateral restraint decreases. If we consider the magmastatic load only, the block will remain stable (or continue to move at constant speed), unless the transient mechanical and thermal pressurization significantly decrease the friction coefficient, increasing the instability of the flank wedge for αN5° (seaward dipping decollement). When the magma overpressure contribution is included in the equilibrium analysis, the ratio between destabilizing and stabilizing forces is of the same order or larger than the coefficient of friction of the basal failure plane, and the block will become unstable (or accelerate), especially in the case of the reduction in friction coefficient. Finally, our work suggests that the major challenge in studying flank instability at Mount Etna is not the lack of an appropriate physical model, but the limited knowledge of the mechanical and geometrical parameters describing the block equilibrium.
    Beschreibung: This work was funded by Istituto Nazionale di Geofisica e Vulcanologia (INGV) and the Italian Dipartimento per la Protezione Civile (DPC) (DPC-INGV project V4 “Flank”).
    Beschreibung: In press
    Beschreibung: 1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
    Beschreibung: 3.2. Tettonica attiva
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Etna ; dike intrusion ; flank instability ; poro-elasticity ; analytical modelling ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.06. Rheology, friction, and structure of fault zones ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 04. Solid Earth::04.07. Tectonophysics::04.07.05. Stress ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.02. Experimental volcanism ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk ; 05. General::05.01. Computational geophysics::05.01.99. General or miscellaneous ; 05. General::05.05. Mathematical geophysics::05.05.99. General or miscellaneous
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 15
    facet.materialart.
    Unbekannt
    Time reverse location of seismic long-period events recorded on Mt Etna (2012)
    Wiley
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: We present the first application of a time reverse location method in a volcanic setting, for a family of long-period (LP) events recorded on Mt Etna. Results are compared with locations determined using a full moment tensor grid search inversion and cross-correlation method. From 2008 June 18 to July 3, 50 broad-band seismic stations were deployed on Mt Etna, Italy, in close proximity to the summit. Two families of LP events were detected with dominant spectral peaks around 0.9 Hz. The large number of stations close to the summit allowed us to locate all events in both families using a time reversal location method. The method involves taking the seismic signal, reversing it in time, and using it as a seismic source in a numerical seismic wave simulator where the reversed signals propagate through the numerical model, interfere constructively and destructively, and focus on the original source location. The source location is the computational cell with the largest displacement magnitude at the time of maximum energy current density inside the grid. Before we located the two LP families we first applied the method to two synthetic data sets and found a good fit between the time reverse location and true synthetic location for a known velocity model. The time reverse location results of the two families show a shallow seismic region close to the summit in agreement with the locations using a moment tensor full waveform inversion method and a cross-correlation location method.
    Beschreibung: Published
    Beschreibung: 452-462
    Beschreibung: 1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attive
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Volcano seismology ; Computational seismology ; Wave propagation ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.06. Seismology::04.06.09. Waves and wave analysis
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 16
    facet.materialart.
    Unbekannt
    Dike emplacement and flank instability at Mount Etna: Constraints from a poro-elastic-model of flank collapse (2011)
    Elsevier B.V.
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: Many volcanic edifices are subject to flank failure, usually produced by a combination of events, rather than any single process. From a dynamic point of view, the cause of collapse can be divided into factors that contribute to an increase in shear stress, and factors that contribute to the reduction in the friction coefficient μ of a potential basal failure plane. We study the potential for flank failure at Mount Etna considering a schematic section of the eastern flank, approximated by a wedge-like block. For such geometry, we perform a (steady state) limit equilibrium analysis: the resolution of the forces parallel to the possible basal failure plane allows us to determine the total force acting on the potentially unstable wedge. An estimate of the relative strength of these forces suggests that, in first approximation, the stability is controlled primarily by the balance between block weight, lithostatic load and magmatic forces. Any other force (sea load, hydrostatic uplift, and the uplift due to mechanical and thermal pore-fluid pressure) may be considered of second order. To study the model sensitivity, we let the inferred slope α of the basal surface failure vary between −10° and 10°, and consider three possible scenarios: no magma loading, magmastatic load, and magmastatic load with magma overpressure. We use error propagation to include in our analysis the uncertainties in the estimates of the mechanics and geometrical parameters controlling the block equilibrium. When there is no magma loading, the ratio between destabilizing and stabilizing forces is usually smaller than the coefficient of friction of the basal failure plane. In the absence of an initiating mechanism, and with the nominal values of the coefficient of friction μ = 0.7 ± 0.1 proposed, the representative wedge will remain stable or continue to move at constant speed. In presence of magmastatic forces, the influence of the lateral restraint decreases. If we consider the magmastatic load only, the block will remain stable (or continue to move at constant speed), unless the transient mechanical and thermal pressurization significantly decrease the friction coefficient, increasing the instability of the flank wedge for α 〉 5° (seaward dipping decollement). When the magma overpressure contribution is included in the equilibrium analysis, the ratio between destabilizing and stabilizing forces is of the same order or larger than the coefficient of friction of the basal failure plane, and the block will become unstable (or accelerate), especially in the case of the reduction in friction coefficient. Finally, our work suggests that the major challenge in studying flank instability at Mount Etna is not the lack of an appropriate physical model, but the limited knowledge of the mechanical and geometrical parameters describing the block equilibrium.
    Beschreibung: This work was funded by Istituto Nazionale di Geofisica e Vulcanologia (INGV) and the Italian Dipartimento per la Protezione Civile (DPC) (DPC-INGV project V4 “Flank”).
    Beschreibung: Published
    Beschreibung: 153-164
    Beschreibung: 3.2. Tettonica attiva
    Beschreibung: 3.5. Geologia e storia dei vulcani ed evoluzione dei magmi
    Beschreibung: 3.6. Fisica del vulcanismo
    Beschreibung: 4.3. TTC - Scenari di pericolosità vulcanica
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Etna ; dike intrusion ; flank instability ; poro-elasticity ; analytical modelling ; 04. Solid Earth::04.01. Earth Interior::04.01.99. General or miscellaneous ; 04. Solid Earth::04.01. Earth Interior::04.01.02. Geological and geophysical evidences of deep processes ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.06. Rheology, friction, and structure of fault zones ; 04. Solid Earth::04.04. Geology::04.04.09. Structural geology ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamics ; 04. Solid Earth::04.07. Tectonophysics::04.07.05. Stress ; 04. Solid Earth::04.07. Tectonophysics::04.07.07. Tectonics ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.03. Magmas ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring ; 04. Solid Earth::04.08. Volcanology::04.08.08. Volcanic risk ; 05. General::05.01. Computational geophysics::05.01.99. General or miscellaneous
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 17
    facet.materialart.
    Unbekannt
    Radon Tells Unexpected Tales of Mount Etna’s Unrest (2018)
    Wiley
    Details
    Publikationsdatum: 2019-03-26
    Beschreibung: Some researchers view radon emissions as a precursor to earthquakes, especially those of high magnitude [e.g., Wang et al., 2014; Lombardi and Voltattorni, 2010], but the debate in the scientific community about the applicability of the gas to surveillance systems remains open. Yet radon “works” at Italy’s Mount Etna, one of the world’s most active volcanoes, although not specifically as a precursor to earthquakes. In a broader sense, this naturally radioactive gas from the decay of uranium in the soil, which has been analyzed at Etna in the past few years, acts as a tracer of eruptive activity and also, in some cases, of seismic–tectonic phenomena. To deepen the understanding of tectonic and eruptive phenomena at Etna, scientists analyzed radon escaping from the ground and compared those data with measurements gathered continuously by instrumental networks on the volcano. Here Etna is a boon to scientists—it’s traced by roads, making it easy to access for scientific observation. Dense monitoring networks, managed by the Istituto Nazionale di Geofisica e Vulcanologia, Catania–Osservatorio Etneo (INGV-OE), have been continuously observing the volcano for more than 40 years. This continuous dense monitoring made the volcano the perfect open-air laboratory for deciphering how eruptive activity may influence radon emissions.
    Beschreibung: This work was supported by the Mediterranean Supersite Volcanoes (MED-SUV) project, which has received funding from the European Union’s Seventh Framework Programme for research, technological development, and demonstration under grant agreement 308665.
    Beschreibung: Published
    Beschreibung: 7
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: N/A or not JCR
    Schlagwort(e): Radon ; seismic activity ; Etna ; volcanic activity ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 18
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    Unbekannt
    Shear-velocity andi anisotropy structure of a retreating extensional forearc (Tuscany, Italy) from receiver functions inversion (2011)
    Wiley
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: We investigate in detail the crustal layering of the ‘Val di Chiana Basin’ (Northern Apennines, Tuscany, Italy) through receiver functions and seismic anisotropy with hexagonal symmetry. The teleseismic data set is recorded in correspondence of a typical foreland basin resulting by the progressive eastward retreat of a regional-scale subduction zone trapped between two continents. We study the azimuthal variations of the computed and binned receiver functions associated to a harmonic angular analysis to emphasize the presence of the dipping and the anisotropic structures. The resulting S-wave velocity model shows interesting and new results for this area that we discuss in a regional geodynamic contest contributing to the knowledge of the structure of the forearc of the subduction zone. A dipping interface (N192°E strike, 18° dip) has been revealed at about 1.5 km depth, that separates the basin sediments and flysch from the carbonates and evaporites. Moreover, we interpret the two upper-crust anisotropic layers (at about 6 and 17 km depth) as the Hercynian Phyllites and Micaschists, of the Metamorphic Tuscan Basement. At relatively shallow depths, the presence of these metamorphic rocks causes the seismic anisotropy in the upper crust. The presence of shallow anisotropic layers is a new and interesting feature, first revealed in the study area. Beneath the crust–mantle transition (Moho), located about 28 km depth, our analysis reveals a 7-km-thick anisotropic layer.
    Beschreibung: Published
    Beschreibung: 545-556
    Beschreibung: 3.3. Geodinamica e struttura dell'interno della Terra
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Seismic anisotopy ; Computational Seismology ; Wave propagation ; Subduction zone process ; Crustal structure ; Europe ; 04. Solid Earth::04.06. Seismology::04.06.07. Tomography and anisotropy
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Materialart: article
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  • 19
    facet.materialart.
    Unbekannt
    Time reverse location of seismic long-period events recorded on Mt Etna (2011)
    Wiley
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: We present the first application of a time reverse location method in a volcanic setting, for a family of long-period (LP) events recorded on Mt Etna. Results are compared with locations determined using a full moment tensor grid search inversion and cross-correlation method. From 2008 June 18 to July 3, 50 broad-band seismic stations were deployed on Mt Etna, Italy, in close proximity to the summit. Two families of LP events were detected with dominant spectral peaks around 0.9 Hz. The large number of stations close to the summit allowed us to locate all events in both families using a time reversal location method. The method involves taking the seismic signal, reversing it in time, and using it as a seismic source in a numerical seismic wave simulator where the reversed signals propagate through the numerical model, interfere constructively and destructively, and focus on the original source location. The source location is the computational cell with the largest displacement magnitude at the time of maximum energy current density inside the grid. Before we located the two LP families we first applied the method to two synthetic data sets and found a good fit between the time reverse location and true synthetic location for a known velocity model. The time reverse location results of the two families show a shallow seismic region close to the summit in agreement with the locations using a moment tensor full waveform inversion method and a cross-correlation location method.
    Beschreibung: In press
    Beschreibung: (11)
    Beschreibung: 1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attive
    Beschreibung: JCR Journal
    Beschreibung: reserved
    Schlagwort(e): Volcano seismology ; Computational seismology ; Wave propagation ; 04. Solid Earth::04.06. Seismology::04.06.08. Volcano seismology ; 04. Solid Earth::04.06. Seismology::04.06.09. Waves and wave analysis
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 20
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    Unbekannt
    Lava flow hazards—An impending threat at Miyakejima volcano, Japan (2016)
    Elsevier B.V.
    Details
    Publikationsdatum: 2017-04-04
    Beschreibung: The majority of the historic eruptions recorded at Miyakejima volcano were fissure eruptions that occurred on the flanks of the volcano. During the last 1100 years, 17 fissure eruptions have been reported with a mean interval of about 76–78 years. In the last century, the mean interval between fissure eruptions decreased to 21–22 years, increasing significantly the threat of lava flowinundations to people and property. Herewe quantify the lava flow hazards posed by effusive eruptions inMiyakejima by combining field data, numerical simulations and probability analysis. Our analysis is the first to assess both the spatiotemporal probability of vent opening, which highlights the areas most likely to host a new eruption, and the lava flow hazard, which shows the probabilities of lava-flow inundation in the next 50 years. Future eruptive vents are expected in the vicinity of the Hatchodaira caldera, radiating from the summit of the volcano toward the costs. Areas more likely to be threatened by lava flows are Ako and Kamitsuki villages, as well as Miike port and Miyakejima airport. Thus, our results can be useful for risk evaluation, investment decisions, and emergency response preparation.
    Beschreibung: Published
    Beschreibung: 1-9
    Beschreibung: 1V. Storia e struttura dei sistemi vulcanici
    Beschreibung: 3V. Dinamiche e scenari eruttivi
    Beschreibung: 5V. Sorveglianza vulcanica ed emergenze
    Beschreibung: 6A. Monitoraggio ambientale, sicurezza e territorio
    Beschreibung: JCR Journal
    Beschreibung: restricted
    Schlagwort(e): MAGFLOW model ; vent opening probability ; 04. Solid Earth::04.02. Exploration geophysics::04.02.99. General or miscellaneous ; 04. Solid Earth::04.04. Geology::04.04.99. General or miscellaneous ; 04. Solid Earth::04.07. Tectonophysics::04.07.99. General or miscellaneous ; 04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 21
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    Hazard from Endogenous Gas Emissions and Phreatic Explosions in Rome City (Italy) (2022)
    Wiley-AGU
    Details
    Publikationsdatum: 2022-02-25
    Beschreibung: A gas blowout during an unauthorised well drilling occurred on 9 June 2020 at the Rome-Ciampino boundary at the periphery of Colli Albani quiescent volcano. This zone hosts a shallow confined gas-pressured aquifer, which recently produced further three gas blowouts. Dangerous atmospheric CO2 and H2S concentrations killed some birds and 12 families were evacuated. The helium isotopic composition indicates that the gas has a magmatic origin. It rises toward the surface along leaky faults, pressurizing the shallow confined aquifer and creating a permanent gas blowout hazard. Colli Albani volcano is characterized by anomalous uplift, release of magmatic gas and episodic seismic crises. Should a volcanic unrest occur, gas hazard would increase in this densely inhabited zone of Rome city, as the input of magmatic gas into the confined aquifer might create overpressure conditions leading to a harmful phreatic explosion, or increase the emission of hazardous gas through newly created fractures.
    Beschreibung: Published
    Beschreibung: e2020GL089797
    Beschreibung: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Beschreibung: JCR Journal
    Schlagwort(e): gas blowouts from drillings ; hazardous CO2 and H2S air concentrations ; anomalous soil CO2 flux ; hazard of a possible phreatic explosion ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 22
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    A Lagrangian stochastic model of a volcanic eruption column (2021)
    Wiley-AGU
    Details
    Publikationsdatum: 2021-12-15
    Beschreibung: 13 pages, 4 figures
    Beschreibung: We develop a Lagrangian stochastic model (LSM) of a volcanic plume in which the mean flow is provided by an integral plume model of the eruption column and fluctuations in the vertical velocity are modelled by a suitably constructed stochastic differential equation. The LSM is applied to the two eruptions considered by Costa et al. (2016) for the volcanic-plume intercomparison study. Vertical profiles of the mass concentration computed from the LSM are compared with equivalent results from a large-eddy simulation (LES) for the case of no ambient wind. The LSM captures the order of magnitude of the LES mass concentrations and some aspects of their profiles. In contrast with a standard integral plume model, i.e. without fluctuations, the mass concentration computed from the LSM decays (to zero) towards the top of the plume which is consistent with the LES plumes. In the lower part of the plume, we show that the presence of ash leads to a peak in the mass concentration at the level at which there is a transition from a negatively buoyant jet to a positively buoyant plume. The model can also account for the ambient wind and moisture.
    Beschreibung: Published
    Beschreibung: e2020JD033699
    Beschreibung: 5V. Processi eruttivi e post-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): Physics - Geophysics; Physics - Geophysics; Physics - Atmospheric and Oceanic Physics; Physics - Fluid Dynamics ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 23
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    Volcano‐Tectonic Setting of the Pisciarelli Fumarole Field, Campi Flegrei Caldera, Southern Italy: Insights Into Fluid Circulation Patterns and Hazard Scenarios (2021)
    Wiley-AGU
    Details
    Publikationsdatum: 2021-12-16
    Beschreibung: Phreatic and hydrothermal eruptions are small energetic explosive events that generally have few to no precursors and represent a considerable hazard in tourist and urban areas. At the Campi Flegrei caldera, these events have occurred at the Solfatara volcano and have likely occurred at the nearby Pisciarelli site, where the most powerful hydrothermal phenomena are located. Here, increased hydrothermal activity has caused relevant morphological changes that has led local authorities to deny access to the site. Stratigraphic, structural, and geophysical investigations have allowed us to reconstruct the volcano-tectonic setting of the area. In particular, we have recognized a fault system and related damage zones that act as the preferred pathway for hydrothermal fluids in the caldera. At the surface, these faults control the migration and/or accumulation of deep-seated gases into the subsoil and the formation of fumaroles and mud pools. We have recognized two main fault systems with different ages that show variable displacements. The electrical anomalies identified by electrical resistivity tomography further highlight the main fault pattern and show the interplay between volcano-tectonic structures and fluid circulation. Host rocks and fault zones may be involved in self-sealing processes and/or rock failure phenomena capable of modifying the fluid pathways and establishing favorable conditions, leading to overpressure and/or rapid decompression of fluids and triggering an explosive event. Furthermore, stratigraphic mapping shows fossil mud pool sediments embedded in an old debris flow located above the modern hydrothermal system. This implies that they were at a higher elevation when they formed. The morphotectonic evolution and intense rock alterations in the area could promote further landslide episodes, producing debris-flow deposits that can cover the active area and possibly trigger hydrothermal/ phreatic events.
    Beschreibung: Published
    Beschreibung: e2020TC006227
    Beschreibung: 2V. Struttura e sistema di alimentazione dei vulcani
    Beschreibung: JCR Journal
    Schlagwort(e): fault system ; hydrothermal fluids ; geoelectrical image ; volcanic hazard ; 04.08. Volcanology ; 04.02. Exploration geophysics ; 04.04. Geology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 24
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    A message from the ‘underground forge of the gods’: history and current eruptions at Mt Etna (2022)
    Wiley
    Details
    Publikationsdatum: 2022-01-11
    Beschreibung: Mt Etna has made headlines over the last weeks and months with spectacular eruptions, some of them highly explosive. This type of paroxysmal eruptive behaviour is characteristic of Etna’s activity over the past few decades and so it is no surprise that Etna is among the most active volcanoes worldwide. Etna is well-known for its extraordinary geology and due to its repeated eruptive activity it provides a continuous supply of new scientific opportunities to understand the inner workings of large basaltic volcanic systems. In addition to its scientific value, Etna is also a world famous tourist attraction and has been listed as a UNESCO World Heritage site in 2013 for its geological and cultural value and not least for its fine agricultural products. Etna’s status as an iconic volcano is not a recent phenomenon; in fact, Etna has been a literary fixture for at least 3000 years, giving rise to many ancient myths and legends that mark it as a special place, deserving of human respect. From the ancient eruptions to the latest events in February–April 2021, people try to explain and understand the processes that occur within and beneath the volcano. In this article, we briefly summarize the recent eruptive activity of Etna as well as the ancient myths and legends that surround this volcano, from the underground forge of Hephaestus to the adventures of Odysseus, all the way to the benefits and dangers the volcano provides to those living on its flanks today.
    Beschreibung: Published
    Beschreibung: 141-149
    Beschreibung: 2TM. Divulgazione Scientifica
    Beschreibung: N/A or not JCR
    Schlagwort(e): Etna, mythology, 2021 paroxysms, economy ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 25
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    Lava Flow Eruption Conditions in the Tharsis Volcanic Province on Mars (2022)
    Wiley-AGU
    Details
    Publikationsdatum: 2022-02-11
    Beschreibung: Volcanism has played a major role in modifying the Martian surface. The Tharsis volcanic province dominates the western hemisphere of the planet with numerous effusive volcanic constructs and deposits. Here, we present the results of an in-depth study aimed at characterizing and modeling the emplacement conditions of 40 lava flows in the Tharsis volcanic province. These lava flows display a range of lengths (∼15–310 km), widths (∼0.5–29 km), and thicknesses (∼11–91 m). The volumes and flow masses range from ∼1 to 440 km3 and ∼1011 to 1014 kg, respectively. Using three different models, we calculated a range of eruption rates (0.3–3.5 × 104 m3/s), viscosities (104–107 Pa s), yield strengths (800–104 Pa), and emplacement times (8 h–11 years). While the flow lengths and volumes are typically larger than terrestrial lava flows by an order of magnitude, rheologies and eruption rates are similar based on our findings. Emplacement times suggest that eruptions were active for long periods of time, which implies the presence and persistence of open subsurface pathways. Differences in flow morphology and emplacement conditions across localities within Tharsis highlight different pathways and volumes of available material between the central volcanoes and the plains. The scale of the eruptions suggests there could have been eruption-driven local, regional, and perhaps, global impacts on the Martian climate. The relatively recent age of the eruptions implies that Mars has retained the capability of producing significant localized volcanism.
    Beschreibung: Published
    Beschreibung: e2020JE006791
    Beschreibung: 5V. Processi eruttivi e post-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): Lava flows ; 05.07. Space and Planetary sciences ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 26
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    Twenty Years Monitoring of Soil CO2 Flux and Seismicity at Cava dei Selci Gas Discharge (Colli Albani Volcano, Italy) (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-02-01
    Beschreibung: © 2022 The Authors. Earth and Space Science published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made
    Beschreibung: Cava dei Selci (CdS) is the main degassing site of the Colli Albani quiescent volcano and since 20 years it is the site of geochemical volcano monitoring. Emitted gas consists mostly of CO2 (≥98 vol.%) with minor H2S, and helium isotopes suggest it has a significant magmatic component. The diffuse soil CO2 flux was monitored in the period 2000–2020, with 55 surveys on a target area. The total CO2 output fluctuates from 5.6 to 24.8 t d −1. The soil CO2 flux per unit surface (average 2.323 kg m −2 d −1) is the highest of 15 Italian actively degassing volcanic and geothermal areas. Soil CO2 flux and environmental parameter data collected over 4-year of continuous monitoring (2004–2008) were analyzed by stochastic Gradient Boosting Trees regression (sGBT), Multiple Linear Regression, and Principal Component Regression. Only sGBT predicts the entire data set and effectively identifies the relationship between soil CO2 flux and environmental parameters. Residuals indicate two anomalous degassing periods (March-2005, summer-2007). Colli Albani area is affected by moderate seismicity (Md ≤ 4). 575 earthquakes occurring from 2009 to 2021 were analyzed determining their location, hypocenter depth, and focal mechanism (of 43 selected events). Evaluation of seismic events occurred across geochemical surveys within 30 km from CdS shows that there is a relationship between CO2 flux, earthquake focal mechanism and depth: shallow strike-slip hypocenters are associated to low fluxes, deep normal-faulting hypocenters to high CO2 output.
    Beschreibung: Published
    Beschreibung: e2021EA001936
    Beschreibung: 9T. Geochimica dei fluidi applicata allo studio e al monitoraggio di aree sismiche
    Beschreibung: JCR Journal
    Schlagwort(e): 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 27
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    Reconstructing Pyroclastic Currents' Source and Flow Parameters From Deposit Characteristics and Numerical Modeling: The Pozzolane Rosse Ignimbrite Case Study (Colli Albani, Italy) (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-03-13
    Beschreibung: In this study, we apply a two-dimensional, transient depth-averaged model to simulate the inertial flow dynamics of caldera-forming pyroclastic currents, using the available data about the Pozzolane Rosse ignimbrite (Colli Albani, Italy) eruption (460 ka, 63 km3 DRE). By performing an extensive set of numerical simulations, we test the effects of the initial parameters of the pyroclastic current (Richardson number, mass flow rate, initial flow density) on simulated deposit characteristics which can be compared with selected ignimbrite field observables, including the deposit dispersal along topography, the maximum distance from source, the deposit thickness, the grain size distribution at different distances, and the emplacement temperature. Results permit us to quantify the first-order dependency of the flow runout on the mass flow rate, and of the deposit thickness decay pattern on the initial mixture density. By using the results of the parametric study we reconstruct the source parameters of the Pozzolane Rosse ignimbrite constrained by the ignimbrite depositional characteristics, including the mass partition into the co-ignimbrite cloud. Despite uncertainties associated with the complex, non-linear interplay between the flow variables, the single-layer, depth-averaged model demonstrates to be suitable for simulating inertial pyroclastic currents, such as those generating large-scale caldera-forming ignimbrites, providing a tool for reconstructing the eruption source parameters from deposits characteristics, and to assess pyroclastic currents' hazard for future eruptions.
    Beschreibung: Published
    Beschreibung: e2021JB023637
    Beschreibung: 1V. Storia eruttiva
    Beschreibung: 5V. Processi eruttivi e post-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): numerical modeling, ignimbrites ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 28
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    Hazardous changes in soil CO2 emissions at Vulcano, Italy, in 2021 (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-01-17
    Beschreibung: A noticeable increase in volcanic outgassing occurred at Vulcano, Italy, in 2021. Although the volcano has not achieved critical conditions to produce an eruption, the soil CO2 emissions have prevented access into some zones of the island, due to the volcanic risk known as the gas hazard. Specialised instruments such as fluxmeters and spectrophotometers were used to measure the soil CO2 flux and the carbon isotopes of CO2 during four soil gas surveys. To understand why the volcanic system evolved towards a period of unrest, we modelled our measurements using mass balance calculations. We find that the CO2 increase, almost ten times its baseline, was most likely due to the instability of a magmatic body within the mantle to crustal boundary known as the Moho discontinuity. Because of this magmatic instability, the volcanic CO2 emissions resumed in some zones of the island where volcanic activity had been dormant for decades. The resumption of volcanic degassing in a short period had not been recorded before at Vulcano, and it is important to understand its cause because future changes in magmatic activity might produce larger CO2 emissions that will have the added risk of gas hazards as well as that of an explosion.
    Beschreibung: The La Fossa volcano on the Island of Vulcano, Italy, showed signs of more energetic fumarolic–solfataric activity during 2021. Several increases in volcanic gas emissions and seismicity, namely “crisis”, punctuated the passive degassing at Vulcano that had ensued after the last 1888–1890 vulcanian eruption. Most of the gases (i.e., up to 90%) were emitted at the crater cone while the diffuse degassing of CO2 at Vulcano Porto accounted for more than 10% of the volcanic emissions. Two anomalous degassing zones at the base of the volcanic cone (i.e., Palizzi and Faraglione) showed notable changes in the gas output during the volcanic crisis. In these zones, increases of soil CO2 flux (φCO2) had several practical implications other than of volcanological interest, owing to the risk related to people’s exposure to volcanic gas emissions. The results of this study reveal variations of the average φCO2 from 74 g m-2 d-1 during September 2021 to 370 g m-2 d-1 in November 2021, which were 27% and 538% higher than the statistical background since 1988 (φCO2 ≈ 58 g m-2 d-1), respectively. These observations helped in volcanic surveillance at Vulcano. The soil CO2 partitioning determined using both φCO2 and carbon isotope measurements, helped track changes in the volcanic CO2 output from 9.97 · 104 kg d-1 to 101.15 · 104 kg d-1. Estimates for volcanic CO2 suggest that the instability of a magmatic body caused a transition from background fumarolic–solfataric activity toward an unrest event after September 2021.
    Beschreibung: Published
    Beschreibung: e2022JB024516
    Beschreibung: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Beschreibung: 6A. Geochimica per l'ambiente e geologia medica
    Beschreibung: 6SR VULCANI – Servizi e ricerca per la società
    Beschreibung: 1IT. Reti di monitoraggio e sorveglianza
    Beschreibung: JCR Journal
    Schlagwort(e): Diffuse degassing ; Soil CO2 flux ; Carbon isotopes ; Volcanic unrest ; Volcanic degassing ; Gas Hazard ; Vulcano, isole Eolie ; Vulcano ; Geochemistry ; Natural hazard ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 29
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    The Interface Between Magma and Earth's Atmosphere (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-01-19
    Beschreibung: 1) We model the chemical kinetics of high-temperature volcanic gas emissions within the first seconds of mixing with atmospheric air 2)We identify key chemical processes within the magma-atmosphere interface and quantify influences on the volcanic plume composition 3)Our results question common assumptions prevailing in volcanic gas geochemistry and refine interpretations of gas emissions from open vents
    Beschreibung: Volatiles released from magma can form bubbles and leave the magma body to eventually mix with atmospheric air. The composition of those volatiles, as derived from measurements made after their emission, is used to draw conclusions on processes in the Earth's interior or their influences on Earth's atmosphere. So far, the discussion of the influence of high-temperature mixing with atmospheric air (in particular oxygen) on the measured volcanic gas composition is almost exclusively based on thermodynamic equilibrium (TE) considerations. By modeling the combined effects of C-H-O-S reaction kinetics, turbulent mixing, and associated cooling during the first seconds after magmatic gas release into the atmosphere we show that the resulting gas compositions generally do not represent TE states, with individual species (e.g., CO, H2, H2S, OCS, SO3, HO2, H2O2) deviating by orders of magnitude from equilibrium levels. Besides revealing the chemical details of high-temperature emission processes, our results question common interpretations of volcanic gas studies, particularly affecting the present understanding of auto-catalytic conversion of volcanic halogen species in the atmosphere and redox state determination from volcanic plume gas measurements.
    Beschreibung: Published
    Beschreibung: e2022GC010671
    Beschreibung: 3V. Proprietà chimico-fisiche dei magmi e dei prodotti vulcanici
    Beschreibung: JCR Journal
    Schlagwort(e): 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 30
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    Detecting volcano-related underground mass changes with a quantum gravimeter (2022)
    Wiley-AGU
    Details
    Publikationsdatum: 2022-08-23
    Beschreibung: We present the world’s first time series acquired in the summit area of an active volcano with an absolute atom interferometry gravimeter. The device was installed ~2.5 km from the active craters of Mt. Etna volcano and produced a continuous high–quality gravity time series, despite the unfavorable environmental conditions at the installation site and the occurrence of phases of high volcanic tremor during the acquisition interval. Comparison with data from other gravimeters installed elsewhere on Mt. Etna highlights correlated anomalies, demonstrating that the quantum device measured gravity variations driven by bulk mass changes. The latter are reflective of volcanic processes, involving the dynamics of magma and exsolved gas in the upper part of Mt. Etna's plumbing system. Our results confirm the operational possibilities of quantum gravimetry and open new horizons for the application of the gravity method in geophysics.
    Beschreibung: NEWTON-g project - H2020, FETOPEN-2016/2017 call (Grant Agreement No 801221)
    Beschreibung: Published
    Beschreibung: e2022GL097814
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Integrated on‐land‐offshore stratigraphy of the Campi Flegrei caldera: new insights into the volcano‐tectonic evolution in the last 15 kyr (2021)
    Wiley
    Details
    Publikationsdatum: 2022-06-22
    Beschreibung: Silicic calderas are volcanic systems whose unrest evolution is more unpredictable than other volcano types because they often do not culminate in an eruption. Their complex structure strongly influences the post-collapse volcano-tectonic evolution, usually coupling volcanism and ground deformation. Among such volcanoes, the Campi Flegrei caldera (southern Italy) is one of the most studied. Significant long- and short-term ground deformations characterize this restless volcano. Several studies performed on the marinecontinental succession exposed in the central sector of the Campi Flegrei caldera provided a reconstruction of ground deformation during the last 15 kyr. However, considering that over one-third of the caldera is presently submerged beneath the Pozzuoli Gulf, a comprehensive stratigraphic on-land-offshore framework is still lacking. This study aims at reconstructing the offshore succession through analysis of high-resolution single and multichannel reflection seismic profiles and correlates the resulting seismic stratigraphic framework with the stratigraphy reconstructed on-land. Results provide new clues on the causative relations between the intra-caldera marine and volcaniclastic sedimentation and the alternating phases of marine transgressions and regressions originated by the interplay between ground deformation and sea-level rise. The volcano-tectonic reconstruction, provided in this work, connects the major caldera floor movements to the large Plinian eruptions of Pomici Principali (12 ka) and Agnano Monte Spina (4.55 ka), with the onset of the first post-caldera doming at ~10.5 ka. We emphasize that ground deformation is usually coupled with volcanic activity, which shows a self-similar pattern, regardless of its scale. Thus, characterizing the long-term deformation history becomes of particular interest and relevance for hazard assessment and definition of future unrest scenarios.
    Beschreibung: Published
    Beschreibung: 855-882
    Beschreibung: 1V. Storia eruttiva
    Beschreibung: JCR Journal
    Schlagwort(e): offshore stratigraphy ; seismic units ; La Starza succession ; volcanism, ; 04.08. Volcanology ; 04.04. Geology ; 04.07. Tectonophysics
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 32
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    Pre‐ and Co‐Eruptive Analysis of the September 2021 Eruption at Cumbre Vieja Volcano (La Palma, Canary Islands) Through DInSAR Measurements and Analytical Modeling (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-01-25
    Beschreibung: We investigate the 19 September 2021 eruption of the Cumbre Vieja volcano (La Palma, Canary Islands, Spain). In particular, we analyze the Differential Interferometric Synthetic Aperture Radar (DInSAR) measurements obtained by processing Sentinel-1 images acquired from both ascending and descending orbits. First, we show the importance, for oceanic islands like La Palma, of investigating DInSAR products retrieved from time series, instead of single interferograms, to effectively remove possible atmospheric artifacts within the displacement measurements. Subsequently, we invert the retrieved data through analytical modeling. Our results highlight that a sill–like source was active in the pre–eruptive phase (8–16 September), whereas the action of two dikes prevailed during the co-eruptive phase (17–22 September). This evolution suggests a process of magma rising through a network of interconnected sills and dikes. The seismicity, that preceded and accompanied the onset of the eruption, is consistent with our findings.
    Beschreibung: Published
    Beschreibung: e2021GL097293
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): La Palma ; La Palma 2021 eruption ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    The Most Intense Deflation of the Last Two Decades at Mt. Etna: The 2019–2021 Evolution of Ground Deformation and Modeled Pressure Sources (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-01-31
    Beschreibung: We analyze Global Navigation Satellite System (GNSS) and tilt data from the permanent monitoring networks of Etna volcano starting just after the 24 December 2018 eruption to an unusual two-month period of deflation in February–March, 2021, which coincided with the occurrence of 17 lava fountain episodes. Based on changes in slope in the GNSS displacement time series, we divide the period starting 7 months after the eruption into five phases, spanning the continued inflation of the edifice punctuated by short periods of effusive and strombolian activity (four phases) and a 2-month phase of intensive deflation. Our model indicates a progressive deepening of the internal pressure sources followed by a fast ascending source starting two-months before the first 2021 paroxysms. We explain these results in light of a recent volcanological model on the nature and behavior of magma ascending through the Etnean feeding system.
    Beschreibung: Open Access Funding provided by Istituto Nazionale di Geofisica e Vulcanologia within the CRUI-CARE Agreement.
    Beschreibung: Published
    Beschreibung: e2021GL095195
    Beschreibung: 4V. Processi pre-eruttivi
    Beschreibung: 5V. Processi eruttivi e post-eruttivi
    Beschreibung: JCR Journal
    Schlagwort(e): 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Imaging the Absorbing Feeding and Eruptive Pathways of Deception Island, Antarctica (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-03-30
    Beschreibung: Deception Island is one of the most active and best-documented volcanoes in Antarctica. Since its last eruption in 1970, several geophysical surveys have targeted reconstructing its magmatic systems. However, geophysics fails to reconstruct the pathways magma and fluids follow from depth to erupt at the surface. Here, novel data selection strategies and multi-frequency absorption inversions have been framed in a Geographical Information System, using all available geological (vents and faults distribution), geochemical and geophysical knowledge of the volcano. The result is the detection of these eruptive pathways. The model offers the first image of the magma and associated fluids pathways feed the 1967, 1969, and 1970 eruptions. Results suggest that future ascending paths might lead to active research bases and zones of planned helicopter rescue. The connection between seismic absorption, temperature, and fluid content makes it a promising attribute for detecting and monitoring eruptions at active calderas.
    Beschreibung: Published
    Beschreibung: e2022GL099540
    Beschreibung: 2V. Struttura e sistema di alimentazione dei vulcani
    Beschreibung: JCR Journal
    Schlagwort(e): 04.02. Exploration geophysics ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 35
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    Slope-break Collisions: Comment on “Insight Into Granular Flow Dynamics Relying on Basal Stress Measurements: From Experimental Flume Tests” by K. Li et al. (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-05-25
    Beschreibung: Numerical simulations show that the positive correlation observed in laboratory experiments by Li et al. (2022) between an increase of grain size and particle agitation, on the one hand, and an increase of granular flow mobility, on the other hand, is not a valid cause-and-effect relationship. In other words, their mobility differential is not caused by a different energy dissipation rate that results from a different grain size content. Instead, the flows stop because of a head-on collision with the horizontal flume at the bottom of a steep 40º incline. Essentially, the slope-break jams the granular movement. Indeed, a combination of laboratory experiments and numerical simulations demonstrated that the mobility of unhindered dense granular flows increases as grain size and clast agitation decrease. Consequently, there is no evidence that the high mobility of large natural rock avalanches is due to an increase of particle agitation.
    Beschreibung: Published
    Beschreibung: e2022JB024799
    Beschreibung: 6V. Pericolosità vulcanica e contributi alla stima del rischio
    Beschreibung: JCR Journal
    Schlagwort(e): Pyroclastic Flows ; Mobility ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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  • 36
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    Quantification of the Volcanic Carbon Dioxide in the Air of Vulcano Porto by Stable Isotope Surveys (2023)
    Wiley-AGU
    Details
    Publikationsdatum: 2023-08-29
    Beschreibung: Injecting volcanic gas into the air leads to an increase in carbon dioxide (CO2) levels compared with background concentrations and may establish gas hazard conditions. This study reports the results of five stable isotope (i.e., δ13C-CO2 and δ18O-CO2) surveys of airborne CO2 on Vulcano from August 2020 to November 2021. To measure CO2 in the air, a mobile laboratory was equipped with a laser-based spectrophotometer that can selectively detect different CO2 isotopologues. Volcanic CO2 has a different isotopic signature than atmospheric CO2 and both δ13C-CO2 and δ18O-CO2 can help trace the injections of volcanic gases into the air. An isotopic mass balance model was developed for partitions CO2 between atmospheric background and volcanic CO2. The results of these studies show that volcanic CO2 emissions and atmospheric circulation deeply affected the concentration of CO2 in the air at Vulcano Porto. Studies of δ13C-CO2 and δ18O-CO2 provide an estimate of volcanic CO2 in the air. These results help identify spatially some points of interest for mitigating volcanic gas emission-related hazards on Vulcano.
    Beschreibung: Istituto Nazionale di Geofisica e Vulcanologia
    Beschreibung: Published
    Beschreibung: e2022JD037706
    Beschreibung: 6A. Geochimica per l'ambiente e geologia medica
    Beschreibung: JCR Journal
    Schlagwort(e): stable isotopes ; atmospheric carbon dioxide ; gas hazard ; geochemical modeling ; volcanic degassing ; volcanic crisis ; Vulcano, isole Eolie ; carbon dioxide ; volcanic gas emissions ; oxygen isotopes ; carbon isotopes ; CO2 ; air CO2 ; Spatial isotope monitoring enables the identification of the origin of CO2 in the air ; Calculating the stable isotope balances enables quantify the volcanic CO2 in the total CO2 in the air ; Significant changes in volcanic degassing increased air CO2 concentration and gas hazard on Vulcano – Italy – in 2021 ; 01.01. Atmosphere ; 04.08. Volcanology ; 03.04. Chemical and biological ; 05.03. Educational, History of Science, Public Issues ; 05.02. Data dissemination
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    A review of the tectonic, volcanological and hazard history of Vulcano (Aeolian Islands, Italy) (2024)
    Wiley
    Details
    Publikationsdatum: 2024-04-08
    Beschreibung: Vulcano is one of the seven volcanic islands composing the Aeolian Islands archipelago (Southern Italy), which also includes three other active volcanoes. The island was orig-inally a stratovolcano like Stromboli; afterwards, its shape turned towards a complex structure composed of several volcanic landforms of different sizes. This is due to the great variability of the tectonic and volcanic phenomena, presently showing a volcano made by two calderas, a lava dome complex and two small active cones. The largest of them is the tuff cone of La Fossa, hosted in the middle of a 3- km-wide caldera struc-ture (La Fossa caldera), whose borders are visible on the southern and western sides of the island. Its last eruption occurred in 1888–1890. At present, Vulcano is charac-terized by weak shallow seismicity and intense fumarolic activity mainly concentrated within the crater of the La Fossa cone and along its rims during a recent unrest phase started in 2021, and measured with a multiparametric monitoring network.
    Beschreibung: Published
    Beschreibung: 471-487
    Beschreibung: OSV4: Preparazione alle crisi vulcaniche
    Beschreibung: JCR Journal
    Schlagwort(e): Aeolian Islands, Vulcano ; multihazard ; plumbing system ; unrest ; volcanic history ; stratigraphy ; tectonics ; 04.08. Volcanology
    Repository-Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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