Case study of a Volcanic Eruption

1. Now watch the following video and look at the images after before completing the tableInspired by Iceland

8. Case study of a Volcanic Eruption Here is what the syllabus says you need to know about volcanoes: Different types of volcanoes; this means shield and ?? volcanoes A case study of a volcanic eruption; its cause(i.e. Plate movements), primary and secondary effects, positive and negative impacts; immediate and long term responses Monitoring and predicting volcanic eruptions.

9. You will know one thing about each of the causes, effects and responses to an eruption You will know several things about each of the causes, effects and responses to an eruption and be able to link most of them together Lesson Objectives on an eruption case study You will know several things about each of the causes, effects and responses to an eruption

10. We are going to look at the eruption of Eyjafjallajökull in Iceland as our case study Introduction to the eruption - including Location

11. Eyjafjalljokull

19. Eyja fjalla jökull Islands glacier mountain

20. EYJAFJALLAJÖKULL ‘A – yar – fi – at – lah – yok – ult’

21. Causes of the eruption • Iceland is situated on the mid Atlantic ridge. This is on the plate boundary between the north American plate and the Eurasian plate

22. Up to 19th March 2010 scientists monitoring tectonic activity detected small earthquakes caused by magma moving through fissures in the Earth’s crust. They predicted that an eruption was close. Fimmvörðuháls Eyjafjallajökull 3. As more magma is stored in the chamber, pressure builds up. Eventually, the pressure is strong enough to start an eruption. 1. Small cracks, or fissures, in the Earth’s crust allow molten magma to force its way towards the surface. 2. Magma chambers are formed close the surface. Magma collects in these. Diagram reference: Keilir - Atlantic Center of Excellence

23. 20th March Magma finds its way to the surface. Lava erupts through a 0.5km long volcanic fissure at Fimmvörðuháls. This is a rocky area between the Eyjafjallajökull and Mýrdalsjökull glaciers.

24. The eruption created spectacular lava flows. As the eruption was not below the ice, there was no danger of flooding. Many people flocked to see the eruption creating ice motorways over the ash covered glaciers.

25. The eruption was considered so safe that tourists, including some ladies in high heels, were helicoptered close to the eruption. Some called the eruption a ‘volcanic Disneyland.’

26. By the 31st March lava and basalt covered around one square kilometre and many thought that the eruption was over.

27. On the 12th April a second volcanic fissure opened and scientists measured a 3.2 magnitude earthquake. The earthquake was close to the surface which suggested that magma was once again on the move.On 13th April another earthquake measuring 2.5 magnitude was recorded beneath the Eyjafjallajökull ice cap.

28. At 1.15am on the 14th April Eyjafjallajökull burst open. The volcanic fissure cut though 200m of ice. Huge plumes of tephra and ash were ejected into the atmosphere and the ice melted.

29. By the 16th April the eruption had caused glacial floods, or  jökulhlaups. Ash had reached up to 8km high in the atmosphere and lava flows reached 3km from the volcanic fissure.

30. What were the main events of the eruption between 19th March and 16th April 2010? Map compiled by Páll Einarsson and Ásta Rut Hjartardóttir, The Geo-science Institute of the University of Iceland 12th April. A second volcanic fissure opened during an earthquake measuring 3.2 magnitude beneath Eyjafjallajökull and many smaller earthquakes were recorded 14-16th April. Over the next four days, ash was ejected up to 8 km high in the atmosphere and lava flowed up to 3 km from the main vent. 13thth April A series of shallow earthquakes were recorded Many thought that the eruption was over. 31st March. New basalt (the rock created by cooling lava) covered around 1 square kilometre This eruption produced a spectacular ‘volcanic Disneyland’ and tourists flocked to the site to see amazing lava flows. 20th March. At 11:30pm a volcanic fissure opened at Fimmvörðuháls, a rocky area between two glaciers 19th March. Scientists monitoring the area measured earthquakes caused by magma moving into fissures 1.15am 14th April. Eyjafjallajökull burst open once more and a fissure opened through 200m of ice covering the volcano. A huge cloud of tephra and ash started to come out of the volcanic vent. Start Here

31. Play video Birth of an Island So that is the introduction and causes done..... Remember the Lesson objectives?

32. You will know one thing about each of the causes, effects and responses to an eruption You will know several things about each of the causes, effects and responses to an eruption and be able to link most of them together Lesson Objectives on an eruption case study You will know several things about each of the causes, effects and responses to an eruption

33. Effects of Eyjafjallajökull primary and secondary effects, positive and negative impacts; immediate and long term responses Use lesson 4 local effects Use lesson 5 global effects