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Volcanic eruption case study (MEDC): Mount Etna
Background
Mount Etna is the highest (3,310m) and the most active volcano in Europe, with the
volcanic history stretching back over 5,000 years in Sicily, where since 2001 it has seen an
eruption every year
It is estimated that nearly 25% of Sicily’s population live on the slopes of Mt Etna, due to
it being a main source of income with agriculture and tourism, where it towers above the
city of Catania
Mt Etna has been classified as a Decade Volcano, due to its activity and nearby
population (being worthy of particular study in light of their history of large, destructive
eruptions and proximity to populated areas)
It has experienced a variety of eruption styles, including violent explosions and
voluminous flows

Causes
Mt Etna is on a destructive plate margin, where the denser Eurasian plate is subducted under
the lighter African plate, forming a subduction zone
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The magma rises through fissures in
the ground and a large swell occurs
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In 2002, a large eruption threw up columns of ask and an earthquake
occurred which was 3-4 on the Richter scale
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Aside from the main vent, fissures open up releasing lava flow from a variety of
locations and ‘hornitos’ (small parasitic cones) splatter lava from the side of the cone

Other hazards:
Seismic activity connecting with eruptive activity: potentially serious damage caused to
buildings and public infrastructure around the volcano

Gas plume emission, volcanic dust and ashfalls: high magnitude explosive events at
summit craters can lead to the formation of eruptive columns of ash, the fallout from
which presents significant problems to settlements and agriculture, and also risks for
road and air traffic
Flank collapse before or following: one of the most hazardous processes that can occur
at a volcano is a collapse of one of its flanks, leading to a huge avalanche of volcanic
debris
Phreatic eruptions: These are stream-driven explosions that occur when water beneath
the ground or on the surface is heated by magma or lava, generating an explosion of
steam, water, ash blocks and lava bombs

Impacts
Primary
Deaths: It is estimated that 77 confirmed deaths can be attributed to eruptions on
Mount Etna, where majority of deaths were caused when visitors strayed into
hazardous areas (SOCIAL)
Ash: A huge column of ash was thrown up that could be seen easily from space and
fell as far away from Libya which was 600km away, which meant there was an
enormous quantity of ash in the atmosphere (ENVIRONMENTAL & ECONOMICAL)
Structural damage: Violent eruptions caused the eastern flanks of the volcano to slip
by up to 2 metres and many of the houses on the flanks of the volcano experienced
structural damage (SOCIAL & ECONOMICAL)
Lava flows/Evacuation: Magma was thrown over 100m into the air and ran quickly
down the mountain
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g
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Local authorities
used holiday homes to rehouse these people (SOCIAL, ECONOMICAL,
ENVIRONMENTAL)
Earthquakes: On 30th October, an earthquake 3-4 on the Richter Scale seriously
damaged many villages in the eastern area of Etna (SOCIAL, ECONOMICAL,
ENVIRONMENTAL)
Secondary

Tourism: Eruption almost completely destroyed the tourist station Piano rovenzana on
the northeastern flank of the volcano part of the tourist station around the Rifugio
Sapienza
...
A
restaurant was destroyed and ski lifts were pushed over (SOCIAL & ECONOMICAL)
Agriculture: Hundreds of hectares of forest that covered the sloped of Mount Etna were
destroyed Farms were destroyed and covered in ash, with farmers losing the crop they
planted and so losing the money that they could have potentially earned
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This meant visitors stayed away due to safety
concerns (SOCIAL & ECONOMICAL)
Businesses: 300 family businesses were affected resulting in loss of earnings for many
people
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Bulldozers were also used to crack
tarmac for building barriers in a car park to try to create a channel to direct the lava away from
residential areas
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The army
also brought in heavy moving earth equipment to block flows
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Medicine: a ship with a medical help with nearby Catania if needed
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6 million was used as immediate financial assistance for
losses in tourism and agriculture
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Damaged
buildings have been rebuilt and scientists improved monitoring of the volcano
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They act fast to get all of the people out of the area and move them to
temporary accommodation
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Data recorded: Data continuously recorded by permanent stations are integrated with discrete
observations, surveys and laboratory analysis to evaluate in real time the activity level of the
volcano and to issue warnings
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