0000000000364949
AUTHOR
Alessandro La Spina
Crater Gas Emissions and the Magma Feeding System of Stromboli Volcano
Quiescent and explosive magma degassing at Stromboli volcano sustains high-temperature crater gas venting and a permanent volcanic plume which constitute key sources of information on the magma supply and dynamics, the physical processes controlling the explosive activity and, more broadly, the volcano feeding system. The chemical composition and the mass output of these crater emissions (gases, trace metals, radioactive isotopes) were measured using different methodologies: within-plume airborne measurements, ground-based plume filtering, and/or in situ analysis, remote UV and open-path Fourier transform infrared absorption spectroscopy. The results obtained, summarized in this paper, demo…
Magmatic Gas Composition Reveals the Source Depth of Slug-Driven Strombolian Explosive Activity
Strombolian-type eruptive activity, common at many volcanoes, consists of regular explosions driven by the bursting of gas slugs that rise faster than surrounding magma. Explosion quakes associated with this activity are usually localized at shallow depth; however, where and how slugs actually form remain poorly constrained. We used spectroscopic measurements performed during both quiescent degassing and explosions on Stromboli volcano (Italy) to demonstrate that gas slugs originate from as deep as the volcano-crust interface (approximately 3 kilometers), where both structural discontinuities and differential bubble-rise speed can promote slug coalescence. The observed decoupling between de…
SEW – Save the Etna World
At more than 3,330 m high and ~40 km wide, Mount Etna in Sicily, Italy, is the highestvolcano in Europe and one of the most active in the world. Etna stands majesticwherever you look at it, showing a distinctive skyline from each side. More than 200,000people live around its mid-slopes, while another 300,000 are in the biggest city, Catania,located at its southern lower slope. The volcano is so imposing that there are manydifferent landscapes and habitats, often highly dissimilar. Ente Parco dell’Etna (EtnaPark) is the institution, started in 1987, covering the core of the volcano, protecting itsbiodiversity, ecosystems and landscapes, and lastly promoting the sustainabledevelopment of loca…
Ground-Based measurements of the 2014-2015 holuhraun volcanic cloud (Iceland)
he 2014–2015 Bárðarbunga fissure eruption at Holuhraun in central Iceland was distinguished by the high emission of gases, in total 9.6 Mt SO2, with almost no tephra. This work collates all ground-based measurements of this extraordinary eruption cloud made under particularly challenging conditions: remote location, optically dense cloud with high SO2 column amounts, low UV intensity, frequent clouds and precipitation, an extensive and hot lava field, developing ramparts, and high-latitude winter conditions. Semi-continuous measurements of SO2 flux with three scanning DOAS instruments were augmented by car traverses along the ring-road and along the lava. The ratios of other gases/SO2 were …