Search results for "etna"
showing 10 items of 193 documents
Understanding the SO 2 degassing budget of Mt Etna’s paroxysms: First clues from the december 2015 sequence
2019
The persistent open-vent activity of basaltic volcanoes is periodically interrupted by spectacular but hazardous paroxysmal explosions. The rapid transition from quiescence to explosive eruption poses a significant challenge for volcanic hazard assessment and mitigation, and improving our understanding of the processes that trigger these paroxysmal events is critical. Although magmatic gas is unquestionably the driver, direct measurements of a paroxysm’s gas flux budget have remained challenging, to date. A particularly violent paroxysmal sequence took place on Etna on December 2015, intermittently involving all summit craters, especially the Voragine (VOR) that had previously displayed no…
Melt inclusions track melt evolution and degassing of Etnean magmas in the last 15 ka
2019
We present major elements compositions and volatiles contents of olivine-hosted melt inclusions from Etna volcano (Italy), which extend the existing database with the aim of interpreting the chemical variability of Etnean magmas over the last 15 ka. Olivine phenocrysts were selected from the most primitive Fall Stratified (FS) eruptive products of picritic composition (Mg# = 67–70, Fo 89–91 ), the Mt. Spagnolo eccentric lavas (Mg# = 52–64, Fo 82–88 ) and among the more recent 2002–2013 eruptive products (Mg# = 33–53, Fo 68–83 ). Crystal fractionation and degassing processes were modeled at temperatures of 1050–1300 °C, pressures <500 MPa, and oxygen fugacity between 1 and 2 log units abo…
Changes in SO2 Flux Regime at Mt. Etna Captured by Automatically Processed Ultraviolet Camera Data
2019
We used a one-year long SO2 flux record, which was obtained using a novel algorithm for real-time automatic processing of ultraviolet (UV) camera data, to characterize changes in degassing dynamics at the Mt. Etna volcano in 2016. These SO2 flux records, when combined with independent thermal and seismic evidence, allowed for capturing switches in activity from paroxysmal explosive eruptions to quiescent degassing. We found SO2 fluxes 1.5−2 times higher than the 2016 average (1588 tons/day) during the Etna’s May 16−25 eruptive paroxysmal activity, and mild but detectable SO2 flux increases more than one month before its onset. The SO2 flux typically peaked during a lava fo…
Active tectonics along the south east offshore margin of Mt. Etna: New insights from high-resolution seismic profiles
2018
The offshore margin of Mt. Etna has been shaped by Middle Pleistocene to Holocene shortening and extension and, more recently, by gravity-related sliding of the volcanic edifice. These processes have acted contemporaneously although the gravitational component largely prevails over the tectonic one. In order to investigate this issue, we focused on the main role of active tectonics along the south-eastern offshore of Mt. Etna by means of marine high-resolution seismic data. Seismic profiles revealed post-220 ka sedimentary deposits unconformably overlaying the Lower-Middle Pleistocene Etnean clayey substratum and volcanics of the Basal Tholeiitic phase and the Timpe phase. Offshore Aci Trez…
Chlorine Partitioning Between a Basaltic Melt and H2O-CO2 Fluids at Mount Etna
2009
Partitioning experiments between a basaltic melt from Mt. Etna and a low-density hydrous fluid or vapor containing H(2)O or H(2)O-CO(2) were performed at 1200-1260 degrees C, at pressures between 1 and 200 MPa, either near the nickel-nickel oxide (NNO) buffer or at two log units above it (NNO + 2), and with different chloride concentrations. Most of the experiments were done at chloride-brine-undersaturated conditions, although at the highest Cl concentrations explored brine saturation might have been reached. The average partition coefficients (D(Cl)(fluid/melt)) over the range of Cl concentrations were derived on a weight basis by plotting the calculated concentrations of Cl in the fluid …
Effect of weak magnetic fields on the in vitro propagation of Genista aetnensis (Raf. Ex Biv.) Dc.
2017
Over the years, many studies have emphasized the importance of the magnetic fields (MF), used as a safe alternative choice to improve agricultural production. The induction effect of different magnetic fields varies depending on the species, explants typology, intensity of magnetic field and period of exposure. The aim of the present study was to investigate the application of a continuous magnetic field induction, at different exposure times, as a production enhancement for in vitro culture of Genista aetnensis, an endemic shrub commonly named 'Mount Etna broom'. An in vitro protocol has been settled for the conservation of the species. Plantlets cultured onto a solified Murashige and Skoo…
The value of by-catch data: how species-specific surveys can serve non-target species
2019
Camera trapping has a wide range of research application, but, while research designs are often focused on the study of a single focal species, cameras can also record other non-target species. Occupancy modeling using by-catch data can be a valuable resource to gain information on these species maximizing the scientific effort and efficiency of wildlife surveys. In this study, we used by-catch data from a European wildcat (Felis silvestris silvestris) survey in Southern Italy to assess the habitat covariates determinant for the occupancy of the crested porcupine (Hystrix cristata). We recorded 33 detections at 17 out of 51 cameras (naive occupancy = 0.33). The best models fitted the data w…
Technical Rules for Connecting PV Systems to the Distribution Grid: A Critical Comparison of the Italian and Vietnamese Frameworks
2018
In the last two decades, starting from the Kyoto protocol, decarbonization has promoted worldwide the rise of distributed generation from renewable energy sources. Currently, Vietnam is still showing a strong dependence on fossil fuels but with a great interest in investing in renewable, especially in photovoltaic (PV) systems. In this paper, the current Vietnamese technical and administrative framework for the connection of PV systems to the power grid is presented and critically compared to the Italian one, in order to define the bases for future cooperation in distributed generation and renewable sectors.
The marine activities performed within the TOMO-ETNA experiment
2016
<p>The TOMO-ETNA experiment was planned in order to obtain a detailed geological and structural model of the continental and oceanic crust beneath Mt. Etna volcano and northeastern Sicily up to the Aeolian Islands (southern Italy), by integrating data from active and passive refraction and reflection seismic methodologies, magnetic and gravity surveys. This paper focuses on the marine activities performed within the experiment, which have been carried out in the Ionian and Tyrrhenian Seas, during three multidisciplinary oceanographic cruises, involving three research vessels (“Sarmiento de Gamboa”, “Galatea” and “Aegaeo”) belonging to different countries and institutions. During the o…
Different Languages - Different Sentence Types? On Exclamative Sentences
2016
It is not equally easy for all languages to establish an exclamative sentence type. It seems the easiest for those languages that feature a morphological marking for an exclamative sentence type like Turkish or Vietnamese. English on the other hand is a language that does not mark exclamative clauses with an easily identifiable marker but uses certain preferred constructions, which allow us to separate a class of ‘exclamative sentences’ from other sentence types. However, there is another class of languages for which it is even harder to determine if ‘exclamative sentences’ exist as a sentence type. In those languages, these sentences share a striking amount of formal properties with senten…