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Survey of 4-11-02
The day 4-11-02 has been performed an
inspection by helicopter and with the boat
of the Coastguard, on Panarea and in the
Lisca Bianca-Dattilo-Bottero. The 3-11-02 in
this area was observed a significant
increase of volcanic activity. Fishermen, in
the early hours of the morning, reported, in
the Lisca Bianca-Dattilo-Bottero,
boiling sea, dead fish on the surface and
intense smell of sulfur. The warning was
confirmed by an initial inspection of the
Civil Protection happened in the late
morning. In Day 4, between Lisca
Bianca and Lisca Nera, were visible three
areas, large few hundred meters, with color
of the sea greatly clearer. They had an
intense lifts clear of gas bubbles. The
first area was traditionally known by divers
for the presence of persistent fumarolic
activity. The second area, located
immediately west of Bottaro, was elongated
in the direction of SSE. On the surface was
visible only one point where the bubble size
metrics, are ascending with considerable
force. The third area, covering an area
significantly smaller than the previous ones,
and is placed instead in the previous SW.
During the inspection were made repeatedly
with the thermal camera, water sampling and
direct measures of temperature. The measures
of temperature and thermal images indicate
that there is an appreciable thermal anomaly.
Temperatures water (22-23 ° C) measured near
the degassing points are not significantly
different from those measured at the pier of
the island. The ph of water is approximately
5.6-5.7 significantly different from that of
seawater. During the inspection was also
visited the beach Calcara, to check any
changes in fumarolic. It does not observe
appreciable changes in the location of
fumaroles and the temperature. The maximum
temperature measured (100 ° C) did not
differ significantly from those reported in
the past. Finally were unfounded reports
received in the day 3 about the existence of
important phenomena of cracking land on the
island of Panarea.
The inspection of 5-11-02: investigations
thermal, structural and marine geology
The 5-11-02 we observed a significant
decrease in intersted area of the phenomena
and of the intensity of degassing. In
particular was especially evident in the
arrival area of bubbles in the immediate
area west of Bottaro. The investigation
thermal once again showing no significant
anomalies.
Framework geological and historical
information
Panarea is the smallest of the Aeolian
islands. It represents what remains of
one of the largest and most ancient
volcanoes in the archipelago, now only seat
of phenomena of late volcanism. It was
already active about 600,000 years ago and
its most recent eruptions are old almost
100,000 years. The building consists of a
truncated cone, for about 1,500 m from a
lobed, and which develops mostly in the east
of the island of Panarea. In this area, in
addition to the island of Basiluzzo, a
seabed between -5 and -10 m, the second
connects the cliffs of Lisca
nera, Bottaro, Lisca Bianca, Panarelli and
Dattilo. The seabed encompasses a vast
depression, deep in 30 m. This structure
probably crater is home to a wide range
fumarolico, high activity, which has a
striking provision precipitated sulfur
whitish. Other notable events fumaroliche
and / or hydrothermal are present in the
surrounding seabed to Basiluzzo, "secca dei
pesci", and on greater island, on Calcara.
The scientist Déodat de Dolomieu describes
these activities late volcanic in his famous
book "Voyage aux Iles Lipari" (Journey to
the Lipari Islands), in 1783. They were
already known and structured to thermal
buildings in Roman times but, without doubt,
go back very far more, because they have had
time to profoundly alter the rocks that
encircle the likely submerged crater
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