Etna

 

Highest european volcano

 


The Etna also called Mongibello (3340 mt.), it is one of the greater active volcanos of the earth, biggest and the most elevated of Europe, it is an imposing conic relief that gets up isolated in shore to the Ionio sea, almost at the half of the Oriental Sicily's coast.

At around 2900 mt. the cone is truncate, in a more remarkable way from the side west, from a vast highland, ancient crater elliptical, on which rises stately the terminal cone, in which opens the actual principal crater.

The ray of visibility of the mountain is of around 150 miles; in the very clear days also 200 miles, so it constitutes an obligatory call for the look until from big distance, practically from all the edges of the Island from the point of the Calabria'speninsula and from the sea, beyond that from the Eolie islands.

Wonderful is the picture that offers, especially in winter and spring, when the superior part of the cone is candid of snow, while the inferior part is blacked of lava or dressed again of luxuriant vegetation, between which inhabited centers and houses isolated rise. The show from the top to the rise of the Sun is fascinating, when the shade of the Volcano pushes beyond the center of the Island.

 


For the terminal withered cone the meridian from central Europe, told also of Etna to 1 hour from Greenwich (15° E). Etna has an area of around 1570 Kmq; the base has a perimeter almost circular, of 212 Km, delimited to east from the sea, to north from the Alcàntara. to west and to south from the Simeto river.

The myth set the forge of Efesto or Volcano on Etna and of the Ciclopi and under of him the giant Encelado or Tìfeo, that writhes and made tremble the ground and puffing caused the eruptions and the issues of smoke.

The philosopher Empedocle (V century b.C.) would have thrown itself in the crater, that would have then thrown again in an explosion his sandal of bronze.


 

 


Contrary to common belief, Etna is not a simple shield or strato volcano. Its shape and structure are extremely asymmetric and complex, and a classification of the mountain on a morphological basis is nearly impossible. The reason for this complexity is that Etna did not grow as one single large cone, but as a succession of volcanic edifices most of which suffered partial collapse at least once during their lifetimes, and whose centers shifted from one place to another.

Several calderas can still be discerned morphologically, the most impressive being the huge Valle del Bove (Valley of the oxen) on the eastern side of the volcano whose latest collapse episodes occurred only a few thousand years ago. Etna's morphology is further complicated by the presence of areas with more frequent eruptive activity, like the Northeast Rift which forms a distinct ridge dotted with eruptive cones and cut by numerous gaping fissures. Hundreds of minor pyroclastic cones are scattered all over the flanks of the mountain, some of which appear to be small volcanoes on their own, with edifice heights of several hundred meters, while many others are much smaller, with heights of only a few tens of meters. These were produced by flank eruptions, the most dangerous, and probably the best documented, type of activity at Etna in recent times.


Etna from Lipari Island


At the summit of the volcano stands a complex of large cones which actually host the four summit craters. This peculiar family of craters, which are somehow connected but show a surprising degree of independence from each other, is a relatively recent feature. One hundred years ago, until 1911, there was one single large cone at the summit of Etna, that was truncated by the 500 m-diameter Central Crater. Two new craters, the Northeast and Southeast Craters, formed in 1911 and 1971, respectively, and have since built their own cones which rival the old central summit cone in size and height. In recent years the Southeast Crater has been particularly active and its growing cone now forms a prominent landmark at the summit of Etna. Viewed from south and southeast it actually seems higher than the central summit cone, but this is an effect of perspective; actually the summit of the Southeast Crater cone is still about 20 m lower than the highest point of the volcano.

 



 
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