THE MOUNT ETNA is an active volcano on the East Coast of Sicily, Italy, in the metropolitan city of Catania. between the cities of Messina and Catania.
The name Etna originated from the Phoenician word "Attuna" meaning "furnace" or "chimney."
The Volcano lies above a convergent plate margin between the African Plate and the Eurasian Plate.
Etna is the tallest active volcano in Europe, currently 3,329m/10,922 ft high, though this varies with summit eruptions. It is also the highest peak in Italy South of the Alps.
Etna covers an area of 1,190km2 / 459sq mi with a basal circumference of 140km. This make Etna by far the largest of the 3 active volcanoes in Italy, being about 2 1/2 times the height of the next largest, Mount Vesuvius.
Only Mount Teide in Tenerife (owned by Spain) surpasses Mount Etna in the whole of the European-North African region. In Greek Mythology, the deadly monster Typhon was trapped under Mount Teide in Tenerife by Zeus, the god of the sky and thunder and king of gods, and the forges of Hephaestus were said to also be located underneath it.
Mount Edna is one of the most active volcanoes in the World and is in an almost constant activity. The fertile volcanic soils supports extensive agriculture, with vineyards and orchards spread across the lower slopes of the Mountain and the broad Plain of Catania to the South.
Volcanic activity first took place at Etna 500,000 years ago, with eruptions occurring beneath the sea off the ancient coastline of Sicily. About 300,000 years ago, eruptions began occurring to the South West of the summit then, before activity moved towards the present centre 170,000 years ago. Eruptions at this time built up the first major volcanic edifice, forming the volcano in alternating explosive and effusive eruptions. The growth of the mountain was occasionally interrupted by major eruptions, leading to the collapse of the summit forming a large cauldron-like (cooking pot) depression.
Etna experienced some highly explosive eruptions, generating a large and fast-moving current of hot gas and volcanic matter up to 700km/h (450mph), which left extensive ash deposits composed of glass shards and crystal fragments. The ash was found as far away as South of Rome's border, 800km/497mi to the North.
The Eastern flank of Etna experienced a catastrophic collapse, thousands of years ago, generating an enormous landslide that left an enormous depression in the side of the volcano, known as Valley of the Ox. Researchers suggest that this occurred around 8,000 years ago, now below sea level, was suddenly abandoned around that time.
Etna's most recent collapse event is thought to have occurred about 2,000 years ago, forming what is known as the Piano Cauldron (Caldera). This cauldron has been almost entirely filled by subsequent lava eruptions, but is still visible as a distinct break in the slope of the mountain near the base of the present-day summit cone.
Etna's eruptions follow a variety of patterns. Most occur at the summit, where there are currently 5 distinct craters. Others eruptions occur on the flanks, which have more than 300 vents ranging in size from small holes in the ground to large craters hundreds of meters across.
Summit eruptions can be highly explosive and spectacular, but rarely threaten the inhabited areas around the volcano. In contrast, flank eruptions can occur down to a few hundred meters altitude, close to or even well within the inhabited areas. Since the year 1600 CE, at least 60 flank eruptions and countless summit eruptions have occurred; nearly half of these have happened since the start of the 20th century. Since the year 2,000, Etna has had 4 flank eruptions.
The 1st known recorded Etna's eruption is that of Diodorus Siculus, a Greek historian, known for writing the Universal History (Bibliotheca Historica), much of which survives, between 60 and 30BC.
The first covers mythic history up to the destruction of Troy, arranged geographically, describing regions around the World from Egypt, India, and Arabia to Greece and Europe. The second covers the Trojan War to the death of Alexander the Great. The third covers the period to about 60 BC. He was born at Agyrium in Sicily (now called Agira). The city was ruled by the Tyrants, one of whom, Agyris, was the most powerful ruler in the centre of Sicily. He was a contemporary of Dyonysius the Elder, and with him successfully resisted the Carthaginian forces led by Mago when they invaded Agyrium in 392 BC. Agirium was not colonized by the Greeks until the Corinthian general Timoleon drove out the last Tyrant in 339BC, settled 10,000 Greeks and erected various splendid buildings. In 396BC, an eruption of Etna thwarted the Carthaginians in their attempt to advance on Syracuse during the Second Sicilian War. Diodorus Siculus credits Heracles with the foundation of pieces of land marked off from common uses and dedicated to sacred cults, such as of Iolaus (Heracles'nephew and lover, through his daughter Leipephilene, he was considered to have fathered the mythic and historic line of the kings of Corinth) and of Geryon (a giant who dwelt on the island Erytheia, and often described as a monster with human faces). The Geryon of Dante's 14th century epic, has become the Monster of Fraud, a beast with enormous dragon-like wings with the paws of a lion, a reptilian body and a scorpion's poisonous sting at the tip of his tail, but with the face of an "honest man." Then Agyrium passed through many hands and in about 1400 it became state property of Sicily. Over the years the town has been influenced by Spanish and Jews arrivals, both leaving their architectural mark, the latter a synagogue.
A particularly violent explosive summit eruption occurred in 122BC, and caused heavy fragments falls to the South East, including the Town of Catania, where many roofs collapsed. To help with the reconstruction after the devastating effects of Etna, the Roman government exempted the population of Catania from paying taxes for 10 years.
Etna's most destructive eruption since 122BC started on March 11, 1669 and produced lava flows that destroyed at least 10 Villages on its Southern flank before reaching the city walls of Catania Town five weeks later, on April 15. The lava was largely diverted by these walls into the sea to the South of the city, filling its harbor. A small portion of lava eventually broke through a fragile section of the city walls on the Western side and destroyed a few buildings, without reaching the centre of the Town. There were not a great number of casualties, however, a strong earthquake 22 years later devastated South East Sicily, including Catania, leaving a great number of casualties.
A large lava flow from an eruption in 1928 led to the destruction of a population centre since the 1669 eruption. The eruption started high on Etna's North East flank on November 2. Then new eruptive fissures opened at decreasing elevations down the flank. The 3rd and most vigorous of these fissures opened late on November 4 at an unusually low elevation, approximately 1,200m/3,937ft above sea-level. The event was used by Benito Mussolini's fascist regime for propaganda purposes, with the evacuation, aid, and rebuilding operations being presented as a models of fascist planning.
Other major eruptions occurred in 1949, 1971, 1981, 1983, and 1991-1993. The eruptions have been remarkable similar. In the 1991-1993 eruption, lava flow was successfully diverted saving the Town of Zafferana from being destroyed by it. Initially, such efforts consisted of the construction of earth barriers built perpendicularly to the flow direction; it was hoped that the eruption would stop before the artificial basins created behind the barriers would be completely filled. Instead the eruption continued, and lava surmounted the barriers, heading directly towards the town. Engineers then decided to use explosives near the source of the lava flow, to disrupt a very efficient lava tube system through which the lava travelled for up to 7km/4mi without essentially losing heat and fluidity. The main explosion destroyed the tube and forced the lava into a new artificial channel, far from the town, and it would have taken months to re-establish a long lava tube. Shortly after the blasting, the rate of lava emission dropped, and during the remainder of the eruption the lava never advanced close to the town again.
In July- August 2001, following 6 years of unusually intense activity at the summit, Etna produced again a flank eruption, involving activity from 7 distinct eruptive fissures mostly on the South slope of the mountain. It was a mass-media eruption, because it occurred at the height of the tourist season and numerous reporters and journalists were already in Italy to cover the G8 summit in Genoa. It was a rather modest-size event by Etna standards.
In 2002-2003, a much larger eruption threw up a huge column of ash that could easily be seen from space and fell as far as Libya, 600km/370mi South across the Mediterranean. The activity caused the Eastern flanks to slip by up to 2 meters.
On September 4, 2007 a spectacular episode of lava fountain occurred from the new vent on the East side of the South East Crater, also producing a plume of ash which fell over the East flank. A lava flow travelled about 4.5km/2.8mi into the Valley of Ox. It was visible far into the Plains of Sicily.
On May 13, 2008 an eruption immediately to the East of Etna's summit was accompanied by a swarm of more than 200 earthquakes and significant ground deformation in the summit area. It continued at a slowly diminishing rate for 417 days, until July 6, 2009 making this the longest flank eruption since the 1991-1993 eruption that lasted 473 days. Previous eruptions had lasted 3 weeks , 3 months, and 6 months, respectively. Lava flows advanced 6.5km during the first few days of this eruption but thereafter stagnated at much minor distances from the vents; during the last months of the eruption lava rarely advanced more than 1km down the slope.
On December 3, 2015 an eruption in the Voragine Crater exibited a lava fountain which reached 1km / 3,300ft in height, with an ash plume which reached 3km/9,800ft in height. The activity continued in the following days, with an ash plume that reached 7km/23,000ft in height that forced Catania airport to shut down for a few hours.
On March 16, 2017 an eruption injured 10 people, including a BBC News television crew, after magma exploded upon contact with snow.
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