The knowledge of the dynamic of the Campi Flegrei calderic system is a primary goal to mitigate the volcanic risk in one of the most densely populated volcanic areas in the world. From 1950 to 1990 ...Campi Flegrei suffered three bradyseismic crises with a total uplift of 4.3 m. After 20 years of subsidence, the uplift started again in 2005 accompained by a low increment of the seismicity rate. In 2012 an increment in the seismic energy release and a variation in the gas composition of the fumaroles of Solfatara (in the central area of the caldera) were recorded. Since then, a slow and progressive increase in phenomena continued until today. We analyze the INGV - Osservatorio Vesuviano seismic catalogue of Campi Flegrei from 2000 to 2020 in order to look for any variation in the seismic parameters and compare them with geochemical monitored ones. A remarkable correlation between independent variables of earthquake cumulative number, CO/CO
values and vertical ground deformation reveals a likely common origin. Moreover the correlation between all the variables here analysed enlightens that the same origin can cause the temporal behavior of all these variables. We interpret the seismological, geochemical and geodetic observable in terms of the injection of magmatic fluids into the hydrothermal system or its pressurization.
Volcanoes in Italy and the role of muon radiography D'Alessandro, Raffaello; Ambrosino, F; Baccani, G ...
Philosophical transactions - Royal Society. Mathematical, Physical and engineering sciences/Philosophical transactions - Royal Society. Mathematical, physical and engineering sciences,
12/2018, Letnik:
377, Številka:
2137
Journal Article
Recenzirano
Odprti dostop
Cosmic-ray muon radiography (muography), an imaging technique that can provide measurements of rock densities within the top few 100 m of a volcanic cone, has now achieved a spatial resolution of the ...order of 10 m in optimal detection conditions. Muography provides images of the top region of a volcano edifice with a resolution that is considerably better than that typically achieved with other conventional methods (i.e. gravimetric). We expect such precise measurements, to provide us with information on anomalies in the rock density distribution, which can be affected by dense lava conduits, low-density magma supply paths or the compression with the depth of the overlying soil. The MUon RAdiography of VESuvius (MURAVES) project is now in its final phase of construction and deployment. Up to four muon hodoscopes, each with a surface of roughly 1 m
, will be installed on the slope of Vesuvius and take data for at least 12 months. We will use the muographic profiles, combined with data from gravimetric and seismic measurement campaigns, to determine the stratigraphy of the lava plug at the bottom of the Vesuvius crater, in order to infer potential eruption pathways. While the MURAVES project unfolds, others are using emulsion detectors on Stromboli to study the lava conduits at the top of the volcano. These measurements are ongoing: they have completed two measurement campaigns and are now performing the first data analysis.This article is part of the Theo Murphy meeting issue 'Cosmic-ray muography'.
Within a general volcanic unrest in the densely urbanized area of Campi Flegrei caldera (Italy) an increase in the activity of Pisciarelli hydrothermal area is occurring. The seismic amplitude of ...Pisciarelli fumarolic tremor is a proxy for the fluid emission rate of the entire Solfatara‐Pisciarelli hydrothermal system. The long‐term analysis indicates a significant increase, by a factor of ~3 of the fumarolic tremor amplitude since May 2017. This increment matches with the trend of geochemical and seismic parameters observed in Campi Flegrei, therefore highlighting that Pisciarelli is a key site to monitor the volcanic unrest underway in this high‐risk caldera. The analysis of data from three closely spaced seismic stations provided new clues about the source mechanism of the tremor. Analyzing the fumarolic tremor amplitude we could also identify an episode of enlargement of the emission area close to the main fumarole of Pisciarelli. We propose a monitoring system based on the fumarolic tremor analysis, which provides real‐time information on the Pisciarelli hydrothermal activity and therefore on the current unrest in Campi Flegrei caldera.
Key Points
Fumarolic tremor indicates a new increase of the Pisciarelli hydrothermal activity linked to the current large‐scale unrest at Campi Flegrei
The fumarolic tremor analysis allowed us to identify an episode of enlargement of Pisciarelli mud emissions
We propose a method for monitoring the hydrothermal system based on proximal measurements of fumarolic tremor
The purpose of the MU-RAY project is to develop an innovative approach to the study of volcanoes and their monitoring based on a particle physics approach. The test site is Vesuvio: one of the higher ...risk volcanoes in the world. In this context, muon radiography is an innovative method of enormous impact. This is an imaging technique which relies on the measurement, by means of a cosmic ray telescope, of the absorption in the volcano of muons with near-horizontal trajectories, produced by the interactions of cosmic rays with the atmosphere. Since 2003 this technique has been successfully used on volcanoes in Japan, providing pictures of their vertices with resolutions much better than those obtained with the traditional techniques based on gravimeters. Researchers from Naples and Florence are currently involved in the construction and testing of a prototype telescope based on the use of bars of plastic scintillator with a triangular section whose scintillation light is collected by special fibres (wave length shifters) and transported to SiPM (Silicon photomultipliers). A complete prototype telescope, consisting of three xy scintillation planes and 1m2 active area has been assembled and is now under test.
The MU-RAY detector for muon radiography of volcanoes Anastasio, A.; Ambrosino, F.; Basta, D. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
12/2013, Letnik:
732
Journal Article, Conference Proceeding
Recenzirano
The MU-RAY detector has been designed to perform muon radiography of volcanoes. The possible use on the field introduces several constraints. First the electric power consumption must be reduced to ...the minimum, so that the detector can be solar-powered. Moreover it must be robust and transportable, for what concerns the front-end electronics and data acquisition. A 1m2 prototype has been constructed and is taking data at Mt. Vesuvius. The detector consists of modules of 32 scintillator bars with wave length shifting fibers and silicon photomultiplier read-out. A dedicated front-end electronics has been developed, based on the SPIROC ASIC. An introduction to muon radiography principles, the MU-RAY detector description and results obtained in laboratory will be presented.
Muon Radiography or muography is based on the measurement of the absorption or scattering of cosmic muons, as they pass through the interior of large scale bodies, In particular, absorption muography ...has been applied to investigate the presence of hidden cavities inside the pyramids or underground, as well as the interior of volcanoes’ edifices. The MURAVES project has the challenging aim of investigating the density distribution inside the summit of Mt. Vesuvius. The information, together with that coming from gravimetric measurements, is useful as input to models, to predict how an eruption may develop. The MURAVES apparatus is a robust and low power consumption muon telescope consisting of an array of three identical and independent muon trackers, which provide in a modular way a total sensitive area of three square meters. Each tracker consists of four doublets of planes of plastic scintillator bars with orthogonal orientation, optically coupled to Silicon photomultipliers for the readout of the signal. The muon telescope has been installed on the slope of the volcano and has collected a first set of data, which are being analyzed.
The MU-RAY project: Volcano radiography with cosmic-ray muons Ambrosi, G.; Ambrosino, F.; Battiston, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2011, Letnik:
628, Številka:
1
Journal Article
Recenzirano
Cosmic-ray muon radiography is a technique for imaging the variation of density inside the top few 100
m of a volcanic cone. With resolutions up to 10s of meters in optimal detection conditions, muon ...radiography can provide images of the top region of a volcano edifice with a resolution that is considerably better than that typically achieved with conventional methods. Such precise measurements are expected to provide us with information on anomalies in the rock density distribution, like those expected from dense lava conduits, low density magma supply paths or the compression with depth of the overlying soil. The MU-RAY project aims at the construction of muon telescopes and the development of new analysis tools for muon radiography. The telescopes are required to be able to work in harsh environment and to have low power consumption, good angular and time resolutions, large active area and modularity. The telescope consists of two
X–
Y planes of 2×2 square meters area made by plastic scintillator strips of triangular shape. Each strip is read by a fast WLS fiber coupled to a silicon photomultiplier. The readout electronics is based on the SPIROC chip.
Sixteen polycyclic aromatic hydrocarbons (PAHs) proposed by the US EPA as priority were analyzed in air and soil samples in the Southwest of Buenos Aires, Argentina, in order to study the levels, ...distribution, sources and fugacity ratios of PAHs, evaluating the relationship between them. For this, 10 passive air samplers (XAD-2® resin) were deployed along the area and replaced three-monthly from January to December 2015. PAHs were analyzed through gas chromatography −mass spectrometry (GC-MS). Results obtained showed that total PAHs levels (∑16) ranged from 27.97 to 1052.99 ng m−3 and from 52.40 to 2118.34 ng. g−1 d.w. for air and soil samples, respectively. The highest air- PAHs levels were registered in Bahía Blanca city (1052.99 ng. m−3, d.w.) an urban-industrial site, while the highest soil-PAHs levels were found in La Vitícola (2118.34 ng. g−1, d.w.), a rural location closed to a high traffic national route. For all sites the highest levels were observed during the winter; however, both spatial and temporal variations were only statistically significant for certain specific PAHs. Diagnostic ratios + PCA, determined dominance of pyrolytic sources. Further, data showed that source of PAHs could be attributed to vehicular and industrial emissions (observed in all periods), biomass combustion (linked mainly to warm period) and domestic emissions (linked mainly to cold period). Finally, fugacity ratios resulted <1, indicating that soil and air samples were not in equilibrium for the majority of PAHs determining a net tendency of air PAHs towards deposition while soil acted principally as a sink.
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•First characterization of air- PAHs using PAS-XAD-2® in SWB, Argentina.•Average Σ 16 PAHs were 199.78 ng m−3 (air) and 348.57 ng. g−1 d.w (soil).•Identification of potential sources showed dominance of pyrolytic origin.•Fugacity ratios revealed a net tendency towards deposition for PAHs in soil.
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