MONTSERRAT casestudy - volcanic event example

Question 1

location of Montserrat volcano

Answer 1

• Caribbean
• northern part of the Lesser Antilles
• island arc formed where the Atlantic tectonic plate subducts beneath the Caribbean plate
• most of islands are composite volcanoes formed as a result of violent eruptions

Question 2

details of Montserrat (e.g size / lava (history))

Answer 2

• only 16km and 10km wide
• built almost entirely of volcanic rock
• lava domes were created as a result of andestic (thick sticky) lava building up at the top of the volcano
• lava becomes too heavy, thus dome collapses, resulting in andesiic lava and pyroclastic flows
• lava flows have left rich volcanic soil supporting an abundance of tropical vegetation and cash crops

Question 3

when was the volcano called that erupted in Montserrat?

Answer 3

Chances Peak

Question 4

eruption of the Chances Peak volcano (Montserrat)?

Answer 4

• 18th July 1985 - south of the island - erupting ash / dush - WAS PREVIOUSLY THOUGHT TO BE EXTINCT - scientists began monitoring gases/microquakes and discovered it was only dormant

Question 5

one month after the eruption (Montserrat)

Answer 5

• evacuation of the South Island - residents were moved to churches/halls in the north of the island

Question 6

April 1996 (Montserrat)

Answer 6

• entire population was forced to leave the capital city of Plymouth

Question 7

second eruption of the Chances Peak volcano

Answer 7

• 25th June 1997
• dome of the volcano collapsed - sending 5 million cubic metres of hot rock and gases down the sides of the Soufrièfe Hills
• South of the island was covered by these pyroclastic flows of hot ash/mud/rock

Question 8

impacts of the Montserrat eruptions

Answer 8

• 19 people killed in fires associated with the pyroclastic flows
• several burn / inhalation injuries
• 2/3 of all houses buried by ash or flattened by rocks
• 3/4 of infrastructure was destroyed
• more than half of the 11,000 population was evacuated to Antigua / USA / UK

Question 9

most recent eruption of the Chances Peak Volcano?

Answer 9

• 11th Feb 2010 - ejected 25km of ash - 10% of lava dome collapses - pyroclastic flows and ash fall

Question 10

Immediate response to the first eruption

Answer 10

• in 1995 the Montserrat Volcano Observatory was set up to closely monitor changes (eruption on 25th July 1997 was successfully predicted)
• Red Cross set up temporary schools / provided medical support and food
• warning systems set up to alert inhabitants e.g. Sirens / speaker systems / via media
• troops from USA and British Navy helped evacuate inhabitants
• UK sent £17 million in emergency aid; to help with temporary buildings and water purification systems

Question 11

Long term responses of the Montserrat volcano eruptions?

Answer 11

• a 3 year redevelopment programme for houses/schools/medical services/infrastructure/agriculture - funded by UK
• a top-heavy population pyramid was created as young people didn’t see an economic future on the island
• by 2005, many people had moved back, but the south of the island (e.g Plymouth) remains an exclusion zone
• fertile soil will mean that land can again be used for crops and farming (re-growing as the ash and lava break down)
• potential for rebuilding tourism; the volcano becoming an attraction; in 2010 National Geographic listed Montserrat as one of the “Top 25 New Trips of 2010”; there’s been a new airport, hotel, and dive shop