Publication Date:
2017-04-04
Description:
Mt. Etna is the highest volcano in Europe, up today it reaches about 3320 m a.s.l. It is
located in the eastern cost of Sicily (Southern Italy) which is characterized by intense
tectonic activity and magmatism (Hirn et al., 1997). The Mt. Etna has a very intense
degassing (Gerlach, 1991, Allard et al., 1991) which occurs both from top craters
and along its flanks, mainly along the active structures (D’alessandro et al. 1995, Giammanco
et al., 1998). In order to monitoring the volcanic activity, since 1989, several
soil CO2 flux measurements have been periodically carried out in some areas of the
volcano characterized by high CO2 emissions. In particular, the selected areas are located
in the SW zone around the Paternò village and in the eastern part of the volcano,
around the village of Zafferana Etnea. The measurements of CO2 flux in the areas
are performed in a regular grid of about 70 sites. In the past the highest values of
CO2 flux were recorded before the 1991-1993 eruption. This was the most important
eruption of the last three century as regard of amount of erupted magma volume (Barberi
et al., 1993). Generally till now the data about peripheral degassing have been
considered only in term of total mean flux leaving aside any consideration about the
spatial distribution in the single area. In the last two years, besides simply considered
the variations of mean flux, an analysis of spatial distributions variations has been
undertaken in order to better understand the relationships between volcano system
modifications and diffuse degassing. During the same period two anomalous episodes
were recorded one on May - September 2005 and the other, on May – July 2006.
These two periods showed on the whole different characteristics. The first anomaly
was more intense in the Zafferana area and was coupled with an intense seismic activity
recorded, nearby this area. Otherwise the second episodes showed the greatest
intensity in Paternò area and coincided with the occurrence of several earthquakes,
with hypocentre placed about 10 km depth, few kilometers north of the Paternò. Furthermore
both the episodes were associated with significantly modifications on spatial
distribution of soil CO2 with shapes and the extents quite different each other. The
two anomalies were due to movement and/or arrive of magma batches. The differences
being between them reflect inequality in the modality and/or type of the magma
rising process. Regarding the occurrence of the last eruptive period (July – December
06) should be noted, that unlike of the almost all previous eruptions, the flux remain
rather high in both the areas, also after the beginning of the eruptive event.
Description:
Published
Description:
Vienna, Austria
Description:
1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive
Description:
open
Keywords:
Soil CO2 flux
;
Mt. Etna
;
04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry
;
04. Solid Earth::04.08. Volcanology::04.08.99. General or miscellaneous
;
04. Solid Earth::04.08. Volcanology::04.08.01. Gases
;
04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Abstract
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