37 research outputs found

    A preliminary census of engineering activities located in Sicily (Southern Italy) which may “potentially” induce seismicity

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    The seismic events caused by human engineering activities are commonly termed as “triggered” and “induced”. This class of earthquakes, though characterized by low-to-moderate magnitude, have significant social and eco- nomical implications since they occur close to the engineering activity responsible for triggering/inducing them and can be felt by the inhabitants living nearby, and may even produce damage. One of the first well-documented examples of induced seismicity was observed in 1932 in Algeria, when a shallow magnitude 3.0 earthquake occurred close to the Oued Fodda Dam. By the continuous global improvement of seismic monitoring networks, numerous other examples of human-induced earthquakes have been identified. Induced earthquakes occur at shallow depths and are related to a number of human activities, such as fluid injection under high pressure (e.g. waste-water disposal in deep wells, hydrofracturing activities in enhanced geothermal systems and oil recovery, shale-gas fracking, natural and CO2 gas storage), hydrocarbon exploitation, groundwater extraction, deep underground mining, large water impoundments and underground nuclear tests. In Italy, induced/triggered seismicity is suspected to have contributed to the disaster of the Vajont dam in 1963. Despite this suspected case and the presence in the Italian territory of a large amount of engineering activities “capable” of inducing seismicity, no extensive researches on this topic have been conducted to date. Hence, in order to improve knowledge and correctly assess the potential hazard at a specific location in the future, here we started a preliminary study on the entire range of engineering activities currently located in Sicily (Southern Italy) which may “potentially” induce seismicity. To this end, we performed: • a preliminary census of all engineering activities located in the study area by collecting all the useful information coming from available on-line catalogues; • a detailed compilation of instrumental and historical seismicity, focal mechanisms solutions, multidisciplinary stress indicators, GPS-based ground deformation field, mapped faults, etc by merging data from on-line catalogues with those reported in literature. Finally, for each individual site, we analysed: i) long-term statistic behaviour of instrumental seismicity (mag- nitude of completeness, seismic release above a threshold magnitude, depth distribution, focal plane solutions); ii) long-term statistic behaviour of historical seismicity (maximum magnitude estimation, recurrence time inter- val, etc); iii) properties and orientation of faults (length, estimated geological slip, kinematics, etc); iv) regional stress (from borehole, seismological and geological observations) and strain (from GPS-based observations) fields.UnpublishedVienna (Austria)6T. Sismicità indotta e caratterizzazione sismica dei sistemi naturaliope

    A preliminary census of engineering activities located in Sicily (Southern Italy) which may “potentially” induce seismicity

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    The seismic events caused by human engineering activities are commonly termed as “triggered” and “induced”. This class of earthquakes, though characterized by low-to-moderate magnitude, have significant social and eco- nomical implications since they occur close to the engineering activity responsible for triggering/inducing them and can be felt by the inhabitants living nearby, and may even produce damage. One of the first well-documented examples of induced seismicity was observed in 1932 in Algeria, when a shallow magnitude 3.0 earthquake occurred close to the Oued Fodda Dam. By the continuous global improvement of seismic monitoring networks, numerous other examples of human-induced earthquakes have been identified. Induced earthquakes occur at shallow depths and are related to a number of human activities, such as fluid injection under high pressure (e.g. waste-water disposal in deep wells, hydrofracturing activities in enhanced geothermal systems and oil recovery, shale-gas fracking, natural and CO2 gas storage), hydrocarbon exploitation, groundwater extraction, deep underground mining, large water impoundments and underground nuclear tests. In Italy, induced/triggered seismicity is suspected to have contributed to the disaster of the Vajont dam in 1963. Despite this suspected case and the presence in the Italian territory of a large amount of engineering activities “capable” of inducing seismicity, no extensive researches on this topic have been conducted to date. Hence, in order to improve knowledge and correctly assess the potential hazard at a specific location in the future, here we started a preliminary study on the entire range of engineering activities currently located in Sicily (Southern Italy) which may “potentially” induce seismicity. To this end, we performed: • a preliminary census of all engineering activities located in the study area by collecting all the useful information coming from available on-line catalogues; • a detailed compilation of instrumental and historical seismicity, focal mechanisms solutions, multidisciplinary stress indicators, GPS-based ground deformation field, mapped faults, etc by merging data from on-line catalogues with those reported in literature. Finally, for each individual site, we analysed: i) long-term statistic behaviour of instrumental seismicity (mag- nitude of completeness, seismic release above a threshold magnitude, depth distribution, focal plane solutions); ii) long-term statistic behaviour of historical seismicity (maximum magnitude estimation, recurrence time inter- val, etc); iii) properties and orientation of faults (length, estimated geological slip, kinematics, etc); iv) regional stress (from borehole, seismological and geological observations) and strain (from GPS-based observations) fields

    Cyclic vomiting syndrome in children: a nationwide survey of current practice on behalf of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) and Italian Society of Pediatric Neurology (SINP)

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    Background: Cyclic Vomiting Syndrome (CVS) is a rare functional gastrointestinal disorder, which has a considerable burden on quality of life of both children and their family. Aim of the study was to evaluate the diagnostic modalities and therapeutic approach to CVS among Italian tertiary care centers and the differences according to subspecialties, as well as to explore whether potential predictive factors associated with either a poor outcome or a response to a specific treatment. Methods: Cross-sectional multicenter web-based survey involving members of the Italian Society of Pediatric Gastroenterology, Hepatology and Nutrition (SIGENP) and Italian Society of Pediatric Neurology (SINP). Results: A total of 67 responses were received and analyzed. Most of the respondent units cared for less than 20 patients. More than half of the patients were referred after 3 to 5 episodes, and a quarter after 5 attacks. We report different diagnostic approaches among Italian clinicians, which was particularly evident when comparing gastroenterologists and neurologists. Moreover, our survey demonstrated a predilection of certain drugs during emetic phase according to specific clinic, which reflects the cultural background of physicians. Conclusion: In conclusion, our survey highlights poor consensus amongst clinicians in our country in the diagnosis and the management of children with CVS, raising the need for a national consensus guideline in order to standardize the practice

    Comprehensive investigation of fission yields by using spallation- and (p,2p)-induced fission reactions in inverse kinematics

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    In the last decades, measurements of spallation, fragmentation and Coulex induced fission reactions in inverse kinematics have provided valuable data to accurately investigate the fission dynamics and nuclear structure at large deformations of a large variety of stable and non-stable heavy nuclei. To go a step further, we propose now to induce fission by the use of quasi-free (p,2p) scattering reactions in inverse kinematics, which allows us to reconstruct the excitation energy of the compound fissioning system by using the four-momenta of the two outgoing protons. Therefore, this new approach might permit to correlate the excitation energy with the charge and mass distributions of the fission fragments and with the fission probabilities, given for the first time direct access to the simultaneous measurement of the fission yield dependence on temperature and fission barrier heights of exotic heavy nuclei, respectively. The first experiment based on this methodology was realized recently at the GSI/FAIR facility and a detailed description of the experimental setup is given here.Comment: 4 pages, 15th International Conference on Nuclear Data for Science and Technology (ND2022

    Quasi-free (p,2p) reactions in inverse kinematics for studying the fission yield dependence on temperature

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    Despite the recent experimental and theoretical progress in the investigation of the nuclear fission process, a complete description still represents a challenge in nuclear physics because it is a very complex dynamical process, whose description involves the coupling between intrinsic and collective degrees of freedom, as well as different quantum-mechanical phenomena. To improve on the existing data on nuclear fission,we produce fission reactions of heavy nuclei in inverse kinematics by using quasi-free (p,2p) scattering, which induce fission through particle-hole excitations that can range from few to ten\u27s of MeV. The measurement of the four-momenta of the two outgoing protons allows to reconstruct the excitation energy of the fissioning nucleus and therefore to study the evolution of the fission yields with temperature. The realization of this kind of experiment requires a complex experimental setup, providing full isotopic identification of both fission fragments and an accurate measurement of the momenta of the two outgoing protons. This was realized recently at the GSI/FAIR facility and here some preliminary results are presented

    Modeling ground deformation associated with the destructive earthquakes occurring on Mt. Etna’s southeastern flank in 1984

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    The Timpe Fault System is the source of very shallow but destructive earthquakes that affect several towns and villages on the eastern flank of Mt. Etna (Italy). In 1984, several seismic events, and specifically on 19 and 25 October, caused one fatality, 12 injuries and produced serious damage in the Zafferana and Acireale territories. This seismicity was mainly related to the activity of the Fiandaca Fault, one of the structures belonging to the Timpe Fault System. We inverted ground deformation data collected by a geodimeter trilateration network set up in 1977 at a low altitude along the eastern side of the volcano in order to define the Timpe Fault System faulting mechanisms linked to the seismicity in 1984. We have found that in the period May 1980–October 1984, the Fiandaca Fault was affected by a strike-slip and normal dip-slip of about 20.4 and 12.7 cm respectively. This result is kinematically consistent with field observations of the coseismic ground ruptures along the fault but it is notably large compared to displacements estimated by seismicity, then suggesting that most of the slip over the fault plane was aseismic. The results once again confirm how seismicity and its relation with ground ruptures and creep displacement represent a very high hazard to the several towns and villages situated along the Timpe Fault System.Published2443–24531V. Storia e struttura dei sistemi vulcaniciJCR Journalope

    Structural features of the 2001 and 2002-2003 eruptions of Mount Etna (Italy): evidence of different triggering mechanisms

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    Mount Etna (Italy) produced two important flank eruptions in 2001 and 2002-2003, which were peculiar for their high degrees of explosivity and for the simultaneous emission of two compositionally distinct magmas. From a strictly volcanological point of view, the 2001 and 2002-2003 eruptions showed many similarities. Both affected two sides of the volcano (the southern and northeastern flanks), and both were actually ¸Stwo-eruptions-in-one¡T, with a part of the activity being fed by the lateral draining of the central conduit system (central-lateral activity), while much of the activity was fed from a source independent of the central conduit system (eccentric activity). However, when placed in a wider geodynamic context, the two eruptions are fundamentally different. While the 2001 eruption was heralded by an intense seismic swarm and vigorous ground deformation, very few such premonitory signs preceded the 2002- 2003 eruption, which, however, was accompanied by a major slip of EtnaŠs unstable eastern to southeastern flank, and by widespread seismicity and ground rupturing in the moving sector. This suggests that the dynamics of magma ascent and eruption were anything but identical in the two eruptions. The deformation of the volcanic edifice during the 2001 eruption clearly indicates forceful dike intrusion, probably under N-S regional compression (tectonic triggering). During the first stage of this eruption, earthquakes began to cluster along the active faults traversing and delimiting the unstable sector on the eastern flank, marking the onset of accelerated spreading of that flank. For the 2002-2003 eruption, nearly all of the seismicity was concentrated along these faults, mostly on the eastern and southeastern flanks, but in September more vigorous flank slip began along the Pernicana Fault System on the northeastern flank of the volcano. Magma migration into the Northeast Rift began as a response to this event, and a second, much more significant slip event five weeks later, permitted the uprise of magma not only on the Northeast Rift, but also on the southern flank. The seismic and deformation data preclude any forceful intrusion of magma in thecase of the 2002-2003 eruption, which was mainly triggered by the large-scale slip of the unstable eastern flank of the volcano (slip triggering)

    Effects of the silica dust on the nasal mucosa of ceramic workers

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    Abstract: Background. Adverse health effects due to occupational exposures are a global public health concern and have been studied for many years. Ceramic workers are occupationally exposed to a wide range of toxic substances as they manage clay (silico-aluminous feldspar mixed with sodium, potassium salts and iron oxide). The objective of this study was to assess the presence of any inflammation or alteration of the nasal mucosa of ceramic workers by nasal cytology. Materials and methods. Twenty-eight ceramic workers from Caltagirone (Italy) were enrolled. Nasal symptoms, atopy, health habits and workplace features were assessed by a special questionnaire, and nasal mucosa health was evaluated by nasal cytology. Results. The cytological study of the nasal mucosa revealed the constant presence of abundant, thick and filamentous mucus, as well as a reorganization of the nasal cellularity with a prevalence of muciparous hyperplasia and metaplasia in the study group, and only in a lesser extent for the subjects with some protective environmental measures. Conclusions. The ceramic workers showed chronic inflammatory rhinitis on nasal cytology, with a remodelling of the nasal mucosa and thick mucus. Nasal cytology may be a helpful tool either for the health surveillance of the ceramic workers, or for the screening of any pathology of the upper airways

    Seismicita' entro un raggio di 40 km intorno a Vulcano nel trimestre aprile-giugno 1985

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    Consiglio Nazionale delle Ricerche, Biblioteca Centrale, P.le Aldo Moro, 7, ROMA (Italia) / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

    Sismicita' entro un raggio di 40 km. intorno a Vulcano nel trimestre ottobre-dicembre 1984

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    Consiglio Nazionale delle Ricerche, Biblioteca Centrale, P.le Aldo Moro, 7, ROMA (Italia) / CNR - Consiglio Nazionale delle RichercheSIGLEITItal
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