Publication Date:
2017-04-04
Description:
Mount Etna in Sicily (973 km2), the most active European
volcano, is known as one of the largest contributors
of magmatic CO2 released to the atmosphere. A
significant part of this gas is released in diffuse form
through the volcano’s flanks, along faults and fractured
zones, particularly around its summit (about 3350 m).
Etna is also characterized by significant and often dramatic
slope failure of its eastern flank, which is thought
to trigger summit collapses and some lateral eruptions.
In order to map the faulted areas near Etna’s summit
and to study possible weak zones, a diffuse CO2 efflux
survey was carried out at Mt. Etna in October, 2008.
A total of 1442 sites were surveyed for soil CO2 efflux
and soil temperature over an area of about 9 km2 that
included most of the summit part of Mt. Etna above
2600 m a.s.l. The results show the presence of several
degassing faults in all of the surveyed area except its
west part, which seems to be structurally stable. Most
of the degassing faults start from the summit craters
and run parallel to the borders of the eastward collapsing
sector of the volcano. Many of them are related to
the development of the South-East Crater, but others
seem to be related to a large buried crater rim, probably
a remnant of the 1669 collapse crater formed during the
largest eruption in the last 2000 years. Some degassing
faults are not accompanied by thermal anomalies, thus
suggesting that the gas source is too deep and/or the
ground permeability is too low to allow high-enthalpy
fluids to reach the surface before their condensation.
These “cold” faults bound the anomalous degassing areas to the west, therefore they would be relatively new
and shallow, suggesting a progressive westward shift of
slope failure.
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
;
soil CO2 effluxes
;
hidden faults
;
soil temperature
;
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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