Monserrat Soufriere Hills

• Background info

  - Sits on a subduction zone where the North atlantic plate is sinking beneath the caribbean plate

  - 80% of the island's infrastructure is laid on the south of the soufriere hills

  - Part of the lesser antilles chain island arc

  - Soufriere hills showed seismic activity in 1930s and 60s so could of predicted the 90s eruption

  - Plymouth is the capital city

  - Hadn't shown any activity for the past 370 years

  - LIC

  - British oversea territory
• Impacts

  - 19 people died

  - 10000 people was threatened

  - First pyroclastic flow fired down the east side of the slope heading for the coast so no one was hurt

  -Total loss of value of people's homes and investment were estimated to be about $1 billion

  - 14 million cubic feet of lava was ejected down the volcano

  - heat from the volcano caused a gas station to ignite and explode

  - 3rd eruption catapulted a column of ash 45000 feet into the air

  - Plymouth and everything west of the Soufriere hills was buried under 12m of mud and ash

  - tourism increased as many people wanted to see the volcano
• Lava dome


  - Rock and ash were growing on the summit of the volcano forming a lava dome

  - Unstable bulbous mass formed by successive deposits of thick, viscous lava

  - 5 months after the eruptions the growth slowed down so the islanders returned

  - Just prior to the eruption the lava dome expanded massively and swelling over the north rim of the crater increased

  -between 12:40 and 12:50 the volcano deflated rapidly and destabilising the outer layer of the dome

  - 12:57 the dome collapsed and created the first pyroclastic flow.

  - Farmers fields were engulfed by the pyroclastic flows

  - after the first and second pyroclastic flow, the valley quickly filed with debris which changed the topography

  - 3rd pyroclastic flow reached 400c and traveled over 80mph. The direction was unpredictable as it did not flow in the same direction as the other flows
• Responses


  - UK gave $17 million in emergency aid

  - UK provided $41 million of long term aid to develop the north-new docks, airports and houses

  - Scientist set up a temporary observatory to monitor the activity and installed 9 seismometers which recorded hybrid earthquakes every 50 seconds

  - The Montserration goverment and the British military evacuated 6000 people to shelters in the north. Many people tried to move back south which created tension and anger. North was underdeveloped and caused chaos. People were granted access to the south to mange their farms

  - exclusion zone set up in the south and west of airport was restricted. Roads was not restricted so people can still go to the south to work

  - scientists installed tilt meters on the slopes to monitor the swelling and contraction of the domes

  - The dangers was broadcasted to the islanders by the local radios

  - helicopters went to rescue the stranded people
• Professor Geoff and Michal Isaac's


  - 10 years earlier they predicted a similar event

  - Sent by the UN to access the risk pose by the volcano

  - There research was designed to help the government make contingency plans in the event of an eruption

  - They advised that they should move the infrastructure to the north as the volcano was still considered active as it displayed seismic activity but the government did not act upon their advice