Publication Date:
2017-04-04
Description:
In 2009, Mt. Etna (Italy) activity was characterised by the
end of a long-lasting flank eruption started on 13 May
2008 and by the opening of a new summit degassing
vent on the E flank of the South-East crater on 6 November.
This was preceded by a sequence of significant
anomalies in volcanic degassing, detected by periodic
measurements of soil CO2 efflux on the east flank of the
volcano, continuous measurements of SO2 flux from five
fixed monitoring stations, and periodic FTIR measurements
of the SO2/HCl and SO2/HF molar ratios in the
volcanic plume. Since April 2009, soil and crater emissions
showed a progressive increase marked at least by
two major steps, in April-May and September-October.
Increases were not observed simultaneously; in fact,
they were detected first in soil CO2 emissions and then,
a few days/weeks later, in crater SO2 flux. Only minor
increases of HCl and HF crater fluxes were observed
between November and December. The highest SO2
and halogens fluxes were recorded in coincidence with
the opening of the November 6 vent. The degassing behaviour
of the volcano in 2009 is consistent with the differential release of magmatic gas species, according
to their different solubilities, from a magma body rising
from ~5 km depth to the surface. Our results suggest
the start of a new phase in Etna’s activity, in which the
new vent might reflect improved efficiency in the release
of magmatic gas through the main feeding system, supplied
by a magma body stored at depths between 4 and
2 km. If degassing at the new vent will remain steadystate,
thus forming a stable feeding system, then its
opening might represent the eastward migration of the
South-East crater activity with the likely formation of a
new stable summit cone.
Description:
Published
Description:
Puerto de la Cruz, Tenerife, Canary Islands, Spain
Description:
1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
Description:
open
Keywords:
Mt. Etna
;
crater degassing
;
soil gases
;
volcanic activity
;
04. Solid Earth::04.08. Volcanology::04.08.01. Gases
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Oral presentation
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