170 research outputs found

    Studi di tomografia locale per la definizione della struttura crostale e subcrostale del Friuli e del Veneto Orientale

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    English: CRUSTAL AND SUB-CRUSTAL STRUCTURE OF FRIULI AND VENETO REGIONS DERIVED FROM LOCAL EARTHQUAKE TOMOGRAPHY The Friuli region is one of the most hazardous area in Italy. Numerous earthquakes have shaken and damaged the region both in historical (1348, 1551) and recent times (1928, 1976). The most recent big earthquake, the M = 6.4 event in 1976, was the reason for starting an intensive study of the area from the geological and geophysical points of view but probably the main consequence of the earthquake was the establishment of a regional seismometric network to monitor the seismic activity in the Friuli enlarged area. West to Friuli is the Veneto region: it is characterized by a seismicity of lower energy but that still deserves a certain care, in particular in the Alpago and Cansiglio sectors where earthquakes of magnitude greater than 5.5 occurred in 1873 and 1936. With the aim to investigate the crustal (and possibly sub-crustal) structures of these regions, a local earthquake tomography has been carried out using data recorded in the period 1995-2002 by the Friuli - Venezia Giulia seismometric network. The obtained tomographic images add only a few details to the knowledge of the area, and resembles already published results, even if the current tomography is able to give images for deeper layers (down to 15 km). In practice, there is a good agreement between the surficial tomographic reconstruction and the shallow geology and it is confirmed the existence of a body with velocity 6.2-6.4 km/s deepening eastwards down to 12-15 km. Since this limit corresponds to the resolving power of the data, no interpretation can be done on whether this body has much deeper roots or not. One main evidence of the joint displaying of occurrence of events and velocity recostructions is that seismicity is strictly associated with, and probably dependent from, this body. Since it would be very important to extend the resolving power to deeper layers, a new tomography is planned for a larger area. In fact, deeper events may be considered when the studied area is larger and, since the rays of these events travel for longer distances, they consequently illuminate deeper layers. In this way some limits of the present tomographic runs could be overcome. Italian: Il Friuli è una delle zone a maggior pericolosità sismica del territorio nazionale. Numerosi terremoti hanno causato gravi distruzioni, infatti, nella regione sia in epoca storica (nel 1348 e nel 1511) sia recentemente (nel 1928 e nel 1976). Il terremoto del 1976, di magnitudo 6.4, ha dato l’avvio a tutta una serie di studi di carattere geologico e geofisico. Tra le iniziative più importanti va ricordata l’installazione delle rete sismometrica regionale. Contigua al Friuli si trova la regione del Veneto, di sismicità sicuramente minore di quella friulana, ma degna di attenzione specialmente nel suo settore orientale (Alpago, Cansiglio) in quanto nel 1873 e nel 1936 la violenza dei sismi superò la magnitudo 5,5. Allo scopo di indagare sulle strutture crostali (e possibilmente sub-crostali) è stata condotta una tomografia sismica con terremoti locali utilizzando un nutrito insieme di dati registrati dalla rete sismometrica regionale nel periodo 1995-2002 in un’area estesa intorno al confine tra Veneto e Friuli - Venezia Giulia, dove molti autori ipotizzano una struttura sismogenetica di svincolo trasversale alle strutture alpine contrapponendosi a quelli che invece propongono continuità nello stile tettonicosismogenetico. I risultati ottenuti aggiungono solo pochi dettagli alle immagini topografiche ottenute da altri lavori, ed in particolare essi sono relativi a profondità maggiori rispetto a quelle indagate nel passato. In pratica, viene confermata la buona coerenza tra immagini topografiche superficiali e le strutture geologiche e la presenza di un corpo con velocità dell’ordine di 6,2-6,4 km/s che, inclinato verso est, si estende fino a 12-15 km di profondità. Purtroppo questo valore coincide con il limite della risoluzione tomografica, e lascia aperta la questione sulla reale estensione in profondità della struttura individuata. Ciò che risulta particolarmente evidente è che la struttura, che è stata interpretata come un cuneo legato all’accorciamento crostale associato con le fasi alpine, è responsabile della sismicità dell’area, o comunque strettamente legata ad essa. Da un punto di vista strettamente metodologico, i risultati mostrano i limiti della inversione tomografica legati alla geometria degli eventi e soprattutto dalla scarsa profondità degli stessi. Malgrado non possa essere considerata soluzione definitiva al problema, la estensione della area da indagare potrebbe parzialmente migliorare le immagini topografiche inserendo terremoti più lontani (e quindi con raggi che si approfondiscono di più) avendo cura di definire la geometria ottimale di inversione

    Studi di tomografia locale per la definizione della struttura crostale e subcrostale del Friuli e del Veneto Orientale

    Get PDF
    English: CRUSTAL AND SUB-CRUSTAL STRUCTURE OF FRIULI AND VENETO REGIONS DERIVED FROM LOCAL EARTHQUAKE TOMOGRAPHY The Friuli region is one of the most hazardous area in Italy. Numerous earthquakes have shaken and damaged the region both in historical (1348, 1551) and recent times (1928, 1976). The most recent big earthquake, the M = 6.4 event in 1976, was the reason for starting an intensive study of the area from the geological and geophysical points of view but probably the main consequence of the earthquake was the establishment of a regional seismometric network to monitor the seismic activity in the Friuli enlarged area. West to Friuli is the Veneto region: it is characterized by a seismicity of lower energy but that still deserves a certain care, in particular in the Alpago and Cansiglio sectors where earthquakes of magnitude greater than 5.5 occurred in 1873 and 1936. With the aim to investigate the crustal (and possibly sub-crustal) structures of these regions, a local earthquake tomography has been carried out using data recorded in the period 1995-2002 by the Friuli - Venezia Giulia seismometric network. The obtained tomographic images add only a few details to the knowledge of the area, and resembles already published results, even if the current tomography is able to give images for deeper layers (down to 15 km). In practice, there is a good agreement between the surficial tomographic reconstruction and the shallow geology and it is confirmed the existence of a body with velocity 6.2-6.4 km/s deepening eastwards down to 12-15 km. Since this limit corresponds to the resolving power of the data, no interpretation can be done on whether this body has much deeper roots or not. One main evidence of the joint displaying of occurrence of events and velocity recostructions is that seismicity is strictly associated with, and probably dependent from, this body. Since it would be very important to extend the resolving power to deeper layers, a new tomography is planned for a larger area. In fact, deeper events may be considered when the studied area is larger and, since the rays of these events travel for longer distances, they consequently illuminate deeper layers. In this way some limits of the present tomographic runs could be overcome. Italian: Il Friuli è una delle zone a maggior pericolosità sismica del territorio nazionale. Numerosi terremoti hanno causato gravi distruzioni, infatti, nella regione sia in epoca storica (nel 1348 e nel 1511) sia recentemente (nel 1928 e nel 1976). Il terremoto del 1976, di magnitudo 6.4, ha dato l’avvio a tutta una serie di studi di carattere geologico e geofisico. Tra le iniziative più importanti va ricordata l’installazione delle rete sismometrica regionale. Contigua al Friuli si trova la regione del Veneto, di sismicità sicuramente minore di quella friulana, ma degna di attenzione specialmente nel suo settore orientale (Alpago, Cansiglio) in quanto nel 1873 e nel 1936 la violenza dei sismi superò la magnitudo 5,5. Allo scopo di indagare sulle strutture crostali (e possibilmente sub-crostali) è stata condotta una tomografia sismica con terremoti locali utilizzando un nutrito insieme di dati registrati dalla rete sismometrica regionale nel periodo 1995-2002 in un’area estesa intorno al confine tra Veneto e Friuli - Venezia Giulia, dove molti autori ipotizzano una struttura sismogenetica di svincolo trasversale alle strutture alpine contrapponendosi a quelli che invece propongono continuità nello stile tettonicosismogenetico. I risultati ottenuti aggiungono solo pochi dettagli alle immagini topografiche ottenute da altri lavori, ed in particolare essi sono relativi a profondità maggiori rispetto a quelle indagate nel passato. In pratica, viene confermata la buona coerenza tra immagini topografiche superficiali e le strutture geologiche e la presenza di un corpo con velocità dell’ordine di 6,2-6,4 km/s che, inclinato verso est, si estende fino a 12-15 km di profondità. Purtroppo questo valore coincide con il limite della risoluzione tomografica, e lascia aperta la questione sulla reale estensione in profondità della struttura individuata. Ciò che risulta particolarmente evidente è che la struttura, che è stata interpretata come un cuneo legato all’accorciamento crostale associato con le fasi alpine, è responsabile della sismicità dell’area, o comunque strettamente legata ad essa. Da un punto di vista strettamente metodologico, i risultati mostrano i limiti della inversione tomografica legati alla geometria degli eventi e soprattutto dalla scarsa profondità degli stessi. Malgrado non possa essere considerata soluzione definitiva al problema, la estensione della area da indagare potrebbe parzialmente migliorare le immagini topografiche inserendo terremoti più lontani (e quindi con raggi che si approfondiscono di più) avendo cura di definire la geometria ottimale di inversione

    Occurrence probability of moderate to large earthquakes in Italy based on new geophysical methods

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    We develop new approaches to calculating 30-year probabilities for occurrence of moderate-to-large earthquakes in Italy. Geodetic techniques and finite-element modelling, aimed to reproduce a large amount of neotectonic data using thin-shell finite element, are used to separately calculate the expected seismicity rates inside seismogenic areas (polygons containing mapped faults and/or suspected or modelled faults). Thirty-year earthquake probabilities obtained from the two approaches show similarities in most of Italy: the largest probabilities are found in the southern Apennines, where they reach values between 10% and 20% for earthquakes of M W ≥ 6.0, and lower than 10% for events with an M W ≥ 6.5

    Recent Advances on assessing seismic hazard and earthquake probabilities in Italy

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    Recent advances on assessing seismic hazard and earthquake probabilities in Ital

    Seismic hazard for the Trans Adriatic Pipeline (TAP). Part 2: broadband scenarios at the Fier Compressor Station (Albania)

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    AbstractTo ensure environmental and public safety, critical facilities require rigorous seismic hazard analysis to define seismic input for their design. We consider the case of the Trans Adriatic Pipeline (TAP), which is a pipeline that transports natural gas from the Caspian Sea to southern Italy, crossing active faults and areas characterized by high seismicity levels. For this pipeline, we develop a Probabilistic Seismic Hazard Assessment (PSHA) for the broader area, and, for the selected critical sites, we perform deterministic seismic hazard assessment (DSHA), by calculating shaking scenarios that account for the physics of the source, propagation, and site effects. This paper presents a DSHA for a compressor station located at Fier, along the Albanian coastal region. Considering the location of the most hazardous faults in the study site, revealed by the PSHA disaggregation, we model the ground motion for two different scenarios to simulate the worst-case scenario for this compressor station. We compute broadband waveforms for receivers on soft soils by applying specific transfer functions estimated from the available geotechnical data for the Fier area. The simulations reproduce the variability observed in the ground motion recorded in the near-earthquake source. The vertical ground motion is strong for receivers placed above the rupture areas and should not be ignored in seismic designs; furthermore, our vertical simulations reproduce the displacement and the static offset of the ground motion highlighted in recent studies. This observation confirms the importance of the DSHA analysis in defining the expected pipeline damage functions and permanent soil deformations

    Earthquake rupture forecasts for the mps19 seismic hazard model of Italy

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    In recent years, new approaches for developing earthquake rupture forecasts (ERFs) have been proposed to be used as an input for probabilistic seismic hazard assessment (PSHA). Zone-based approaches with seismicity rates derived from earthquake catalogs are commonly used in many countries as the standard for national seismic hazard models. In Italy, a single zone-based ERF is currently the basis for the official seismic hazard model. In this contribution, we present eleven new ERFs, including five zone-based, two smoothed seismicity-based, two fault-based, and two geodetic-based, used for a new PSH model in Italy. The ERFs were tested against observed seismicity and were subject to an elicitation procedure by a panel of PSHA experts to verify the scientific robustness and consistency of the forecasts with respect to the observations. Tests and elicitation were finalized to weight the ERFs. The results show a good response to the new inputs to observed seismicity in the last few centuries. The entire approach was a first attempt to build a community-based set of ERFs for an Italian PSHA model. The project involved a large number of seismic hazard practitioners, with their knowledge and experience, and the development of different models to capture and explore a large range of epistemic uncertainties in building ERFs, and represents an important step forward for the new national seismic hazard model

    Clinical Effectiveness of Budesonide/Formoterol Fumarate Easyhaler(A (R)) for Patients with Poorly Controlled Obstructive Airway Disease: a Real-World Study of Patient-Reported Outcomes

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    The effectiveness of inhaled therapies can be influenced by many factors, including the type of inhaler, which may have clinical implications. We report a real-world, multicenter, open-label, non-randomized, non-interventional study conducted by 200 pulmonologists across 200 centers in Hungary. The effectiveness of budesonide/formoterol inhalation therapy in daily clinical practice, delivered via the Bufomix Easyhaler(A (R)), was evaluated in patients with asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap (ACO). Effectiveness was assessed after 12 weeks of treatment by spirometry, the Asthma Control Test, mini-Asthma Quality of Life Questionnaire, COPD Assessment Test and modified Medical Research Council dyspnea scale. Patient satisfaction with the Bufomix Easyhaler(A (R)) and physicians' assessments (ease of use and time taken to learn the technique) were also assessed. A total of 1498 patients with obstructive airway disease were evaluated (asthma: n = 621; COPD: n = 778; ACO: n = 99), of whom 455 (30.4%) were newly diagnosed inhaler-na 0.002) were reported after 12 weeks of Bufomix Easyhaler(A (R)) use. Improvements were observed in both inhaler-na 90.0% of physicians described the Bufomix Easyhaler(A (R)) as easy to teach; 73.8% and 98.9% of patients learned the technique within 5 and 10 min of teaching, respectively. Twelve weeks' treatment with the Bufomix Easyhaler(A (R)) resulted in significant improvements in disease control and quality of life. The Bufomix Easyhaler(A (R)) was considered easy to use, and most patients were satisfied with the inhaler. Results confirm the real-world effectiveness of the Bufomix Easyhaler(A (R)) in the treatment of adult outpatients with obstructive airway disease. Orion Corp., Orion Pharma
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