Volcanic Hazards - Impacts and Responses Flashcards
Describe the location of Soufriere Hills volcano in Montserrat and what plate margin it is situated on?
The volcano is located on a small island in the Caribbean Sea. Montserrat is above a destructive plate margin, where the North American plate is being forced under the Caribbean plate.
When was the Soufriere Hills eruptions?
Between June and September 1997 there was a series of large eruptions
How much material was released in the largest eruption?
In the largest eruption, about 4-5 million metres cubed of material was released over a 20 minute period.
What were the economic impacts of the volcanic eruption?
- The total loss in value of people’s homes and investments was estimated to be about £1 billion.
- Over 20 villages and two thirds of homes on the island were destroyed by pyroclastic flows.
- Tourists stayed away, and businesses were destroyed, disrupting the economy. However, tourism on the island is now increasing as people come to see the volcano.
- Schools, hospitals, the airport and the port were destroyed.
What are the environmental impacts of the volcanic eruption?
- Large areas were covered with volcanic material-the capital city of Plymouth was buried under 12 m of mud and ash.
- Vegetation and farmland were destroyed
- Volcanic ash from the eruption has improved soil fertility.
What were the social impacts of the volcanic eruption?
- 19 people dies and seven were injured
- Hundreds of people lost their homes.
- Fires destroyed many buildings, e.g. local government offices, the police headquarters and petrol stations.
- The population has declined-8000 of the islands 12000 inhabitants left after the eruption, and many still haven’t returned.
What were the short term responses to the volcanic eruption?
People were evacuated from the south to safe areas in the north.
Shelters were built to house evacuees.
Temporary infrastructure was also built.
The UK provided 17 million emergency aid.
Local emergency services provided support units to search for and rescue survivors.
A risk map was created, and an exclusion zone is in place. The south of the island is off limits while the volcano is still intermittently active.
Warned government in advance to evacuate but this was ignored.
What were the long term responses to the volcanic eruption?
The UK has provided £41 million of long term aid to develop the north of the island- new docks, an airport and houses have been built with this. (Dependant on UK aid)
The Montserrat Volcano Observatory has been set up to try and predict future eruptions.
Describe the location of Mount Etna
Located in northern Sicily, Italy
Describe the formation of Etna
Etna is a stratovolcano (35,000 years
old) but built on a shield volcano
(500,000 years old).
Describe the plate tectonics of Etna?
On a continental-continental
subduction zone: African Plate
subducts beneath the Eurasian Plate
Describe the lava of Etna?
Both, viscous, basaltic and, less
viscous, rhyolitic/andesitic lava. It has two separate magma chambers.
When did the eruption occur?
27th October 2002/ 28th Jan 2003 eruptions.
What were the effects of the eruptions?
Forest fires and vegetation damage Schools closed Skiing areas of Piano Provenzana almost destroyed — tourism losses Fontanarossa Airport (Catania International) closed due to ash Malta: ash blackened cars Buildings destroyed by an earthquake on 29th October on southern flank Cleaning efforts cost 2 billion lire Scenic ruin: Piccolo Rifugio damaged in the lava flows 32 injured
What were the responses to the eruption?
Bulldozers worked to divert lava away from the town of Linguaglosa Volcanologists called in to advise on demolishing lava channels with explosives and building earth embankments: used at Rifugio Sapienza Flights diverted to Palermo, away from the ash cloud $8 million in tax breaks and financial assistance given to businesses.
