Publication Date:
2021-12-23
Description:
The structure of an active volcano is highly dependent on the interplay between the
geodynamic context, the tectonic assessment as well as the magmatic processes in the
plumbing system. This complex scenario, widely explored at Etna during the last 40 years,
is nevertheless incomplete for the recent historical activity. In 1763 two eruptions occurred
along the west flank of the volcano. There, an eruption started on 6th February and formed
the scoria cone of Mt. Nuovo and a roughly 4-km-long lava flow field. Another small scoria
cone, known as Mt. Mezza Luna, is not dated in historical sources. It is located just 1 km
eastward of Mt. Nuovo and produced a 700mlong flow field. We focused on the activity of
Mts. Nuovo and Mezza Luna for several reasons. First, the old geological maps and
volcanological catalogues indicate that Mt. Mezza Luna and Mt. Nuovo cones were formed
during the same eruption, while historical sources described Mt. Nuovo’s activity as
producing a single scoria cone and do not give information about the formation of Mt.
Mezza Luna. Second, petrologic studies highlight that the products of Mt. Mezza Luna are
similar to the sub-aphyric Etna basalts; they preserve a composition relatively close to Etna
primitive magma which were also erupted in 1763, during La Montagnola flank eruption,
which took place along the South Rift of the volcano. Third, the two scoria cones built up
along the so-called West Rift of Etna, which represents one of the main magma-ascent
zones of the volcano. We applied a multidisciplinary approach that could prove useful for
other volcanoes whose past activity is still to be reconstructed. Critical reviews of historical
records, new field surveys, petrochemical analyses and petrologic modelling of the Mts.
Nuovo and Mezza Luna eruptions have been integrated with literature data. The results
allowed improving the stratigraphic record of historical eruptions reported in the Mount
Etna Geological map, modelling the sub-volcanic magmatic processes responsible for
magma differentiation, and evidencing recurrent mechanisms of magma transfer at Etna.
Indeed, the intrusion of a deep primitive magma along the South Rift is often associated
with the activation of other rift zones that erupt residual magma stored in the shallow
plumbing system.
Description:
This study has been funded by the EC FP7 Mediterranean Supersite Volcanoes project (ECGA 308665) of the European Commission
Description:
Published
Description:
774361
Description:
2V. Struttura e sistema di alimentazione dei vulcani
Description:
JCR Journal
Keywords:
Etna volcano, historical activity, historical geological maps, stratigraphic sequence, deep magma composition, volcano rift zones
;
04.08. Volcanology
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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