0000000000416218
AUTHOR
M. Bitetto
Changes in SO2 flux degassing regime prior to the 2014 Stromboli eruption
Volcanic eruptions are often accompanied by release of huge amounts of magmatic SO2. Capturing sizeable precursory SO2 flux variations prior to eruption has revealed far more challenging, instead, in spite of the recent progresses in instrumental gas monitoring. Here, we report on the SO2 fluxes variations we detected at Stromboli volcano prior to the effusive eruption started on the 6th August 2014. The SO2 fluxes were regularly quantified at high-rate (0.5 Hz) using two fully autonomous permanent SO2 camera devices installed - within the framework the ERC-FP7 project "Bridge"- at two sites located at 0.5 km (Roccette) and 1.75 km (Sciara del Fuoco rim) distance from the crater terrace. Th…
A novel and inexpensive method for measuring volcanic plume water fluxes at high temporal resolution
© 2017 by the authors.Water vapour (H2O) is the dominant species in volcanic gas plumes. Therefore,measurements of H2O fluxes could provide valuable constraints on subsurface degassing and magmatic processes. However, due to the large and variable concentration of this species in the background atmosphere, little attention has been devoted to monitoring the emission rates of this species from volcanoes. Instead, the focus has been placed on remote measurements of SO2, which is present in far lower abundances in plumes, and therefore provides poorer single flux proxies for overall degassing conditions. Here, we present a new technique for the measurement of H2O emissions at degassing volcano…
First gas flux measurements of conduit permeability decrease prior to Strombolian eruption at Stromboli volcano (Italy)
Strombolian eruptions can be described in terms of growth, coalescence, and rise of a gas pocket (aka slug) bursting at the surface of a vent. This model overlooks that the transition to explosive regimes is mostly controlled by the permeability in the upper part of a volcanic conduit. We report here on the first gas flux measurements of Strombolian explosions from a vent that exhibited a significant decrease of passive degassing tens of second prior to the onset of the explosion. This particular explosive activity took place during the July 2014 lava overflows, when the magma level inside the conduit rose up to the crater terrace. The amount of gas that accumulated before the eruption is i…
Spatially resolved SO2 flux emissions from Mt Etna
Abstract We report on a systematic record of SO2 flux emissions from individual vents of Etna volcano (Sicily), which we obtained using a permanent UV camera network. Observations were carried out in summer 2014, a period encompassing two eruptive episodes of the New South East Crater (NSEC) and a fissure‐fed eruption in the upper Valle del Bove. We demonstrate that our vent‐resolved SO2 flux time series allow capturing shifts in activity from one vent to another and contribute to our understanding of Etna's shallow plumbing system structure. We find that the fissure eruption contributed ~50,000 t of SO2 or ~30% of the SO2 emitted by the volcano during the 5 July to 10 August eruptive inter…