WARNING:
Access to the summit area is VERY
DANGEROUS. Violent eruptive episodes are occurring
every few days at the Southeast Crater, and heavy showers of
tephra (including clasts tens of centimeters in diameter) may
occur up to several kilometers away. Lava may also arrive rapidly
at up to 1.5 km of distance from the crater on the plain between
Torre del Filosofo, Monte Frumento Supino, and the summit crater
cones. The Torre del Filosofo area, which is familiar to many
excursionists, is presently not a safe place at all. Tourists
are presently not allowed to go beyond 2700 m elevation,
and they should make excursions only with the mountain guides.
Besides this, weather conditions are often unstable. Strong
wind, snow or rain and clouds are occuring frequently in the
summit area, even during the summer, and one can get easily
lost. The mountain guides can be contacted at the cable car
(near the Rifugio Sapienza) on the southern side of Etna, or
(during the summer) at the hotel "Le Betulle" at Piano
Provenzana, on the northern side.
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NEW:
PHOTOS OF THE 14 JUNE 2000 PAROXYSM
AT THE SE CRATER
NEW:
SOUNDS AND MOVIE CLIPS OF THE
24 JUNE 2000 PAROXYSM AT THE SE CRATER
31 July 2000 update.
During the past sixteen days, Etna has remained in a state of near
complete calm. The latest significant activity was a paroxysmal eruptive
episode on the late evening of 24 June at the SE Crater, the 64th
in five months. After that event, the summit craters of the volcano
have become progressively less active, and at this moment there is
nothing to indicate when and where eruptive activity will resume.
The levels of activity during July have been lower than any time since
the spectacular summit eruptions began five years ago.
Since Behncke's latest visit to the summit craters on 14 July, observations
of the craters have been made sporadically by Claude Grandpey and
Jean Pierre Kloster, both of the French Association Volcanologique
Européenne (L.A.V.E.). On 12 July, Kloster observed deep seated
explosive activity within the NW vent of the Bocca Nuova, with ejections
of glowing lava fragments which did not rise as high as the rim of
the vent. This was the most recent observation of any eruptive activity
at Etna; during the following days the intensity of degassing decreased
(Grandpey describes this as a diminution of the gas pressure). Gas
rings, which had been produced at the E vent of the Bocca Nuova every
few minutes for about five months, became less frequent, and the last
rings were observed on 16 July. When Grandpey visited the Bocca Nuova
on 24 and 26 July, the vent that had produced the gas rings was quiet,
and another vent nearby had noisy gas explosions every now and then.
The NW vent was a bottomless pit and did not show any signs of activity
except weak degassing. During Grandpey's visits, the Voragine was
fairly quiet as well, with relatively weak gas emissions from its
two vents. On 24 July the smaller of these vents, which had formed
sometime in May, was completely quiet, but had resumed degassing two
days later.
The NE Crater was inactive as well, although collapse of the walls
of its central pit occasionally generated dilute plumes of brownish
ash. Similar plumes were seen at the NW vent of the Bocca Nuova on
some days in late July. The SE Crater has remained almost totally
quiet, with some gas emission from fumaroles near its crater rim.
15 July 2000 update.
There has been no paroxysm at the SE Crater for three weeks, and it
is well possible that another amazing chapter in the fascinating story
of Etna's summit eruptions (which began almost five years ago, in
late July 1995) has come to a close.
Eruptive activity in the summit area has been at quite low levels
since the SE Crater last erupted on the late evening of 24 June. Most
visible activity has consisted of voluminous gas emissions from the
Bocca Nuova, the Voragine and the NE Crater. However, there may be
deep-seated magmatic activity in the NW vent of the Bocca Nuova -
there are unconfirmed reports about ejections of incandescent lava
fragments in that vent on 12 July, but those fragments did not reach
the rim of the vent.
On the afternoon of 14 July, Boris Behncke, his brother Jakob Behncke
with his fiancee Eva Maria Wiegershausen and David Bryant visited
the summit area during heavy storm and some weather cloud. Breaks
in the clouds permitted occasional observations of the activity at
the Voragine and in the NW vent of the Bocca Nuova. No visible eruptive
activity was seen (or heard) in the latter vent, but there was a vigorous
gas plume rising from the large central pit of the Voragine, which
was seen to be strongly pulsating after the weather clouds dissipated,
shortly before sunset. No ejections of solid material or glow were
observed after sunset. Nonetheless the gas plume was distinctly more
voluminous and active than during Behncke's and Bryant's previous
visits in the past few weeks.
From these very incomplete and preliminary observations it might be
concluded that there is a slight increase in gas emission from the
Voragine, whereas the occurrence of magmatic activity in the NW vent
of the Bocca Nuova has to await further confirmation. An increase
of the activity at these two craters would be no surprise; it is very
likely that magma continues to rise through the central conduit system
of Etna towards the summit craters, and renewed eruptive activity
in that area will likely occur within the near future.
9 July 2000 update.
The SE Crater has remained unusually quiet during the past two weeks.
This is the fifteenth consecutive day without any eruptive activity
at the crater which has produced 64 episodes of violent paroxysmal
activity in the 5 months following 26 January 2000. No repose interval
between paroxysms during that period were as long as the period of
inactivity since the latest of those paroxysms, which occurred on
the late evening of 24 June.
Little has changed at the other three summit craters of Etna. These
craters were visited by Behncke and Bryant on the afternoon of 29
June, and the only change since their previous visit 9 days earlier
was a slight enlargement of the new fuming pit in the SW part of the
Voragine. The NE Crater continued its vigorous degassing activity,
which takes place at a depth of hundreds of meters in its active pit.
Sometimes the resulting gas plume mixed with fine lithic ash. Deep-seated
explosive activity in the E vent of the Bocca Nuova produced gas rings,
adding to the many thousands of gas rings emitted from that vent during
the previous months.
Some who have observed the volcano during the dramatic period of paroxysms
at the SE Crater are now beginning to speculate that these peculiar
eruptive manifestations may be over. It has always been clear that
the SE Crater could not go on like that forever, and that something
else would happen at Etna after that. But what will happen, if that
series of paroxysms has really ended, and why did it end - if it really
has ended?
Maybe magma supply to the SE Crater has slowed. Maybe it becomes more
and more difficult for the magma to rise to the crater, whose cone
has grown higher and higher in the past six months, and thus the repose
interval between eruptive episodes becomes longer. But if magma continues
to be fed into the conduit below the crater, one day it will erupt
- either from the crater itself, or from fissures on its slopes or
at its base, like it did for 9 months in 1999.
On the other hand the SE Crater conduit may have become blocked, and
any fresh magma rising in the central conduit system of Etna may be
diverted towards one or more of the other summit craters. This would
eventually lead to renewed eruptive activity in one of those craters,
where the amount of gas emission appears to be higher since about
two months.
It cannot be excluded that a fresh batch of gas-rich magma rising
up within the volcano might cause the slopes of Etna to fracture,
leading to a flank eruption. In this moment there are few signs that
enable us to speculate about the future at Etna - the only thing that
is certain is that it will not remain quiet for long.
Several
other web pages covering the recent and ongoing eruptions of the Southeast
Crater are now available; these contain photos and movie clips of
some of the most spectacular moments of that period.
Etna
in 2000 - a list of all paroxysms at the SE Crater since 26 January
and photos (this site)
Extremely
spectacular video clips, taken by British cameraman and film maker
David Bryant on 15 February 2000
At
"Italy's Volcanoes" -
At Stromboli On-line
An
interview with Boris Behncke, made in late February 2000 by a BBC
team
and a video
clip (RealPlayer)
Photos
of the eruptive activity, 15-23 February 2000, by Tom Pfeiffer (University
of Arhus, Denmark)
Photos
of an eruptive episode on 13 February 2000, posted on the web site
of the Association Volcanologique Européenne, Paris, France
Photos
of the 15 February 2000 paroxysm of the SE Crater, by Thorsten Boeckel,
Germany
Photos
by Marco Fulle, 15-20 February 2000, at Stromboli On-line - very high
quality, as usual
Charles
Rivière's Etna home page, with many photos and video clips
(the most recent of the paroxysm of 5 May 2000), frequent updates,
and other, highly interesting items (in French and English)