Search results for "Stromboli"

Dynamics of mild strombolian activity on Mt. Etna

2015

Abstract Here we report the first measurements of gas masses released during a rare period of strombolian activity at the Bocca Nuova crater, Mt. Etna, Sicily. UV camera data acquired for 195 events over an ≈ 27 minute period (27th July 2012) indicate erupted SO2 masses ranging from ≈ 0.1 to ≈ 14 kg per event, with corresponding total gas masses of ≈ 0.1 to 74 kg. Thus, the activity was characterised by more frequent and smaller events than typically associated with strombolian activity on volcanoes such as Stromboli. Events releasing larger measured gas masses were followed by relatively long repose periods before the following burst, a feature not previously reported on from gas measureme…

2017

Strombolian volcanism is a ubiquitous form of activity, driven by the ascent and bursting of bubbles of slug morphology. Whilst considerable attention has been devoted to understanding the behaviour of individual slugs in this regime, relatively little is known about how inter-slug interactions modify flow conditions. Recently, we reported on high temporal frequency strombolian activity on Etna, in which the larger erupted slug masses were followed by longer intervals before the following explosion than the smaller bursts (Pering et al., 2015). We hypothesised that this behaviour arose from the coalescence of ascending slugs causing a prolonged lag before arrival of the next distinct bubble…

The 2007 eruption of Stromboli volcano: Insights from real-time measurement of the volcanic gas plume CO2/SO2 ratio

2009

Abstract The recent eruption of Stromboli in February–April 2007 offered a unique chance to test our current understanding of processes driving the transition from ordinary (persistent Strombolian) to effusive activity, and the ability of instrumental geophysical and geochemical networks to interpret and predict these events. Here, we report on the results of two years of in-situ sensing of the CO 2 /SO 2 ratio in Stromboli's volcanic gas plume, in the attempt to put constraints on the trigger mechanisms and dynamics of the eruption. We show that large variations of the plume CO 2 /SO 2 ratio (range, 0.9–26) preceded the onset of the eruption (since December 2007), interrupting a period of …

The 15 March 2007 explosive crisis at Stromboli Volcano, Italy: assessing physical parameters through a multidisciplinary approach

2011

Basaltic volcanoes are dominated by lava emission and mild explosive activity. Nevertheless, many basaltic systems exhibit, from time to time, poorly documented and little-understood violent explosions. A short-lived, multiblast explosive crisis (paroxysmal explosion) occurred on 15 March 2007 during an effusive eruptive crisis at Stromboli (Italy). The explosive crisis, which started at 20:38:14 UT, had a total duration of ∼5 min. The combined use of multiparametric data collected by the permanent instrumental networks (seismic, acoustic, and thermal records) and a field survey carried out immediately after the event enabled us to constrain the eruptive dynamics and quantify physical param…

Determination and comparison of acidic gas ratios at the Stromboli Volcano and Mount Etna obtained by various active alkaline traps

2013

BLAST WAVES AT YASUR VOLCANO

2013

Infrasonic and seismic waveforms were collected during violent strombolian activity at Yasur Volcano (Vanuatu). Averaging similar to 3000 seismic events showed stable waveforms, evidencing a low-frequency (0.1-0.3Hz) signal preceding similar to 5-6s the explosion. Infrasonic waveforms were mostly asymmetric with a sharp compressive (5-106Pa) onset, followed by a small long-lasting rarefaction phase. Regardless of the pressure amplitude, the ratio between the positive and negative phases was constant. These waveform characteristics closely resembled blast waves. Infrared imagery showed an apparent cold spherical front similar to 20 m thick, which moved between 342 and 405m/s before the explo…

Shallow magma dynamics at open-vent volcanoes tracked by coupled thermal and SO2 observations

2022

Open-vent volcanic activity is typically sustained by ascent and degassing of shallow magma, in which the rate of magma supply to the upper feeding system largely exceeds the rate of magma eruption. Such unbalance between supplied (input) and erupted (output) magma rates is thought to result from steady, degassing-driven, convective magma overturning in a shallow conduit/feeding dyke. Here, we characterize shallow magma circulation at Stromboli volcano by combining independent observations of heat (Volcanic Radiative Power; via satellite images) and gas (SO2, via UV camera) output in a temporal interval (from August 1, 2018 to April 30, 2020) encompassing the summer 2019 effusive eruption a…

Principles and method for H2 and CO2 monitoring in volcanic areas: preliminary results for Stromboli and Etna volcanoes

2011

CO2 output discharged from Stromboli Island (Italy)

2013

Abstract Total CO 2 output from soil gas and plume, discharged from the Stromboli Island, was estimated. The CO 2 emission of the plume emitted from the active crater was estimated on the basis of the SO 2 crater output and C/S ratio, while CO 2 discharged through diffuse soil emission was quantified on the basis of 419 measurements of CO 2 fluxes from the soil of the whole island, performed by using the accumulation chamber method. The results indicate an overall output of ≅ 416 t day − 1 of CO 2 from the island. The main contribution to the total CO 2 output comes from the summit area (396 t day − 1 ), with 370 t/day from the active crater and 26 t day − 1 from the Pizzo sopra La Fossa so…

Conduit dynamics and post explosion degassing on Stromboli: A combined UV camera and numerical modeling treatment.

2016

Abstract Recent gas flux measurements have shown that Strombolian explosions are often followed by periods of elevated flux, or “gas codas,” with durations of order a minute. Here we present UV camera data from 200 events recorded at Stromboli volcano to constrain the nature of these codas for the first time, providing estimates for combined explosion plus coda SO2 masses of ≈18–225 kg. Numerical simulations of gas slug ascent show that substantial proportions of the initial gas mass can be distributed into a train of “daughter bubbles” released from the base of the slug, which we suggest, generate the codas, on bursting at the surface. This process could also cause transitioning of slugs i…