Publication Date:
2017-04-04
Description:
From October 2008 to November 2009, soil CO2 and Rn
surveys have been performed, in order to get insights
upon active tectonic structures in a densely populated
sector of the South-Eastern flank of Mt Etna, which
seems to be involved in the flank dynamics, as highlighted
by satellite data (INSAR). The investigated area
extends about 150 km2, in an area, where INSAR data
detected several lineaments not known from geological
surveys. The method adopted to perform the 345
soil CO2 measurements is the “dynamic concentration”
method (Gurrieri and Valenza, 1988; Camarda et
al., 2006), which provides a proxy for soil CO2 fluxes.
The gas measurements have been performed along
transects roughly orthogonal to the lineaments, with
measurement points spaced about 100m. The method
appeared more efficient than a regular grid, which
would have requested much more measurements and
a time-consuming field work. CO2 data show the highest
values, along each transect, very close to the lineaments
evidenced by INSAR observations. Anomalous
values also occur in correspondence of eruptive fractures.
In some portions of the investigated area, rather
broad anomalies are observed, and this would imply
that, instead of a single well-defined lineament, a wider
fault zone probably exists. A set of both CO2 and Rn
measurements, performed at about 900m of altitude,
are worth of note, because they allow identifying the
lengthening of detected lineaments at higher elevation,
where the INSAR data are poorly informative. Finally, at
the base of the volcanic edifice, the soil gas anomalies
strikingly define the active structures until almost
the coastline through the northern periphery of Catania
town. The coupling of the two methods thus revealed as
a powerful tool to detect buried active structures, which
conversely do not show significant field evidences.
Description:
Published
Description:
Puerto de la Cruz, Tenerife, Canary Islands, Spain
Description:
1.5. TTC - Sorveglianza dell'attività eruttiva dei vulcani
Description:
open
Keywords:
Mt. Etna
;
soil gases
;
gravitational spreading
;
INSAR
;
04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Poster session
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