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SICILY - ETNA VULCANO
ACCOMMODATION
LEISURE
SHOPPING
EXCURSIONS
Mount Etna is Europe's largest volcano (its volume is at least 350 km3), and one of the most active (in the sense of "productive" and eruption frequency) volcanoes on Earth, with frequent periods of intermittent to persistent activity in the summit area and major eruptions from new vents on its flanks every 1-20 years. The main feature of Etnean activity is voluminous lava emission, but strong explosive activity occurs occasionally, mostly from its presently four summit craters. Some of the eruptions from its flanks also show high degrees of explosivity, such as those in 1669, 1879, and 2002-2003.
Etna lies near the eastern (Ionian) coast of Sicily and occupies a surface area of around 1200 km2 with a perimeter exceeding 135 km. Its summit height varies frequently in function of eruptive activity or minor collapse events at the summit craters: through the early 1980s it showed a net increase by nearly 100 m to an unprecedented 3350 m in 1981, but since then it has progressively decreased to 3315 m at the beginning of the new millennium. The cone of the youngest of the four summit craters, the Southeast Crater, which was born in 1971, underwent a period of dramatic growth between 1998 and 2001 but remained a few tens of meters lower than the highest point at the summit, the Northeast Crater, and has not erupted since July 2001.
The name Etna probably has its origin in a mixture of the Latin and Greek words for "to burn", although an alternative hypothesis is that it is actually derived from the Phoenician word "athana", which means "furnace". Both hypotheses appear quite plausible and show how early populations near the volcano were impressed by its frequent eruptions.
Many geographic maps of Etna show a second name
at the site of the volcano, Mongibello, a name derived from a mixture
of the Roman word mons and the Arabian word gibele, or jebel, both
of which mean "mountain". Etna has thus the privilege to
be "Mount Mountain" in the mentality of the people living
around it, and this is justified. In Sicily Etna is THE mountain,
'a muntagna in the local dialect. It is another noteworthy detail
of the consideration Etna enjoys in the hearts of the people dwelling
at its sides that the mountain is considered to be female which is
not a typical way of considering mountains in Europe. Etna is the
big Mamma (and when seeing it with its many little cones from flank
eruptions, this idea is quite understandable) who gives and takes,
and has created this particular place on Earth.
Etna is particular for a number of reasons. First, it has the longest record of historical eruptions (see Volcanoes of the World, 1994 edition) among all volcanoes on this planet, its first historically documented eruption occurring at about 1500 BC. The total number of eruptions is 209 (18 among them questionable) through late 1993 (Volcanoes of the World). To these, there have now to be added the spectacular and vigorous summit eruptions of 1995-2001, the flank eruption of July-August 2001, the modest summit eruptions of the summer of 2002, and the dramatic flank eruption that lasted from October 2002 until late January 2003. Certainly we will not have to wait long to add yet another eruption, either at the summit or somewhere on the flanks, to this impressive record.
Etna lies in an area that is still not well understood from a geological standpoint. While some scientists relate, in a broader sense, the Etnean volcanism to subduction of the Ionian oceanic seafloor beneath the Calabrian Arc (with volcanism on the Aeolian Islands as one consequence), others postulate a hot spot beneath Etna, thus explaining its high lava production and fluid mafic magmas. Still another hypothesis sees Etna in a complex rifting environment. Among the few things which are quite well understood is the fact that the volcano lies at the intersection of several major regional fault systems, and this probably facilitates the uprise of magma right in this place. It is evident that Etna lies in a very complex geodynamic environment hardly comparable to any other region on Earth. There is some evidence that Etna is but the most recent manifestation of volcanism fed from a very long-lived mantle source, having caused numerous earlier phases of mafic volcanism in the Monti Iblei, SE Sicily, from the late Triassic to the early Pleistocene.
Although it is generally considered a rather benign volcano, like Kilauea on Hawaii and Piton de la Fournaise on Réunion island in the Indian Ocean, in the sense that it does not produce devastating explosive eruptions, Etna's eruptions represent a significant threat to human property and dwellings in the vicinity. This is mainly due to the frequency of eruptions on the flanks, sometimes at low elevation and thus close to inhabited areas, and to the presence of numerous towns and villages on the volcano's flanks, especially on the southern and southeastern sides. On several occasions during history, population centers have been partially or totally destroyed by lava flows, most recently in 1669 and 1928, and much more often has cultivated land been buried by lava flows. Lava flows are in fact produced during all eruptions of Etna and represent by far the greatest hazard to human property. But although it generally does not produce powerful explosive eruptions like Mount St. Helens or Pinatubo, or some of its Italian companion volcanos such as Vesuvio and Vulcano, Etna's explosive potential has been underestimated until recently. The flank eruptions in 2001 and 2002-2003 have not only shown that Etna is well capable of significant explosive activity, but also that the society living next to the volcano has grown highly vulnerable, with ground and air traffic being most sensible to ash falls.
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