Volcanoes - Physical features

Question 1

Why is magma viscosity relevant?

Answer 1

The more viscous the lava, the greater the potential for explosive eruptions, which represent the greatest potential hazards

Question 2

Viscosity of magma at Nyiragongo

Answer 2

Fluid (low silica content)

Question 3

Viscosity of magma at Pinatubo

Answer 3

Fluid (gas-charged)

Question 4

Viscosity of magma at Eyjafjallajokull

Answer 4

Relatively viscous

Question 5

Tectonics of Nyiragongo

Answer 5

East African Rift Valley - constructive and a hotspot (BBC)

Question 6

Tectonics of Pinatubo and what effects this has

Answer 6

Destructive plate boundary (Eurasian and Philippines plates) - as one plate subducts, there’s a huge build up of pressure, resulting in very violent and dangerous eruptions

Question 7

Tectonics of Eyjafjallajokull and what effects this has

Answer 7

Constructive plate boundary (North American and Eurasian plates) - volcanoes at these boundaries erupt frequently, but usually not violently and are associated with lava flows and ash

Question 8

Explosiveness of Nyiragongo

Answer 8

1 - gentle

Question 9

Explosiveness of Pintaubo

Answer 9

6 - colossal

Question 10

Explosiveness of Eyjafjallajokull

Answer 10

4 - cataclysmic

Question 11

Materials ejected by Nyiragongo

Answer 11

Lava flows, ash cloud

Question 12

Materials ejected by Pinatubo

Answer 12

Lava flows, ash cloud, pyroclastic flows, sulphur dioxide

Question 13

Materials ejected by Eyjafjallajokull

Answer 13

Lava flows, ash cloud