Anatomy of a Paroxysmal Lava Fountain at Etna Volcano: The ...
The volcano Etna
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Transcript of The volcano Etna
It is 3.322 metres (10.922 ft) high,
though the height varies with summit
eruptions.
Etna covers an area of
1,190 km² (460 sq mi) with
a basal circumference
of 140 km.
The Mediterranean area is a convergent boundary where the Eurasian and African plates move toward one another and
collide. These two plates form a subduction zone as the African plate dives under the Eurasian plate. As a result of pressure, friction, and plate material melting in the mantle,
earthquakes and volcanoes are common.
- in the north the Aeolian Islands’ volcanism provocated by the melting of continental crust of the African plate.- in the south Etna’s volcanism due to the magma that comes out from the mantle (30 km deepness) as the subduction of the African plate causes the crack of the continental crust.
The current structure of Mount Etna is the effect of a long and complex eruptive history. The growth of the mountain was occasionally interrupted by major eruptions, leading to the
collapse of the summit to form calderas. We can divide Etna’s evolution in 4 phases:
First phase: ”pre-Etnean”
Second phase: “Ancient Etna”
Third phase: “Trifoglietto II”
Fourth phase: “Mongibello”
Volcanic activity in the Etnean area began around 0.5 million years ago. Its products were mainly submarine lavas and volcaniclastics of
tholeiitic composition. The famous outcrops of Acicastello and nearby locations contain pillow lavasproduced by this early activity.
This phase of volcanism took place in a vast marine gulf, extending over part of the area occupied by the present Etna. The gulf was
filled by sediments intermixed with a regional tectonic uplift. Then the suaerial eruptions began .
The various eruptions created a stratovolcano. Today Etna is by far the largest of the three active volcanoes in Italy and one of the most active volcanoes in the world. It is still in an almost constant state of activity.
Etna’s vegetation is one of the most various in Sicily.
The volcanic eruptions makes fertile the territory and changes very often the landscape.
Under 2000 mt there are vineyards,brooms and hazelnut or oak woods.
Over about 2000 mt there are Beech and birch woods.
In the higher altitude of the mountain there isn’t any vegetation that can survives.
The Etna birch (Betula aetnensis) is very similar to the Northern
Europe one, but during the millennia has evolved so that many naturalists consider it an
endemic variety of Etna. A typical feature of the birch
is the color pinkish-white of the cortex, that tends to epidermal
desquamation in horizontal bands. The leaf has a bright green
color, small in size and serrated edges.
The branches are very thin and flexible.
Also has strong detoxifying properties and is used
against somechronic rheumatic diseases and against hair loss.
Logging and the pratice of hunting wild caused the extinction of wolfs,wild boars,deer and roe deer.Despite this,on the volcano,still live porcupines,foxes, wild cats, martens, rabbits, hares, and among the smaller animals,weasels, hedgehogs, dormice, dormouse.
Etna’s wildlife also includes snakes, as the viper or the green lizard, and a big variety of birds, for example the barn owl and the golden eagle.
Since ancient times the rich volcanic soils of Mount Etna has allowed people to live on agriculture and livestock. Surprising and varied agricultural landscapes are set among forests and lava flows, forming a mosaic environment of rare beauty. The presence of man on the volcano for thousands of years has left a deep imprint: monumental works of terracing, warehouses,wineries, dot the slopes of the "Mountain". The most common kinds of agriculture in Etna’s territory are vineyards and orchards of olives, hazelnuts, pistacchio and citrus, expecially oranges.
2001 eruption
2004 eruption
2006 eruption
2011 eruption
Made by:Dario Borrometi
Alessandro NicotraLuca Nicotra
