1.4 Volcanic Eruptions

Question 1

what made the 2010 iceland volcanic eruption so disastrous?

Answer 1

ash got into the jet stream which carried it over northern europe

Question 2

what were the impacts of the 2010 iceland eruption?
(2 points)

Answer 2

flights were grounded for 10 days costing the aviation industry 2.2 billion euros and affecting 10 million passengers
halted the production of the nissan cube

Question 3

what causes a volcanic eruption?

Answer 3

a fracture in the earth’s crust allowing magma and gasses to erupt through it

Question 4

what is an active volcano?

Answer 4

a volcano that is likely to erupt

Question 5

what is a dormant volcano?

Answer 5

a volcano that isn’t erupting now but it is likely to in the future

Question 6

what is an extinct volcano?

Answer 6

a volcano that is not likely to erupt

Question 7

what are primary hazards of a volcanic eruption?
(4 points)

Answer 7

lava flows
pyroclastic flows
ash and tephra fall
gas eruptions

Question 8

what is a lava flow?

Answer 8

lava flowing out of the volcano
usually slow moving so not a threat

Question 9

what is a pyroclastic flow?

Answer 9

fast-moving rock, ash and gas
very dangerous

Question 10

what is ash and tephra fall?

Answer 10

rock fragments and ash blasted out of the vents during the eruption which damage buildings/infrastructure, cause low visibility and injure/kill people

Question 11

what is a gas eruption?

Answer 11

water vapor, co2 and sulphur dioxide travel far distances and are dangerous to humans, animals and plants

Question 12

what are secondary hazards of a volcanic eruption?

Answer 12

lahars
jokulhlaups

Question 13

what is a lahar?

Answer 13

particles in the atmosphere trigger heavy rainfall which remobilises ash and loose rock causing it to flow down the hill slope very quickly

Question 14

what is a jokulhlaup?

Answer 14

a volcanic eruption melting snow and ice causing glacial outburst floods

Question 15

when was the montserrat volcanic eruption?

Answer 15

18th april 1995

Question 16

what erupted out of the volcano in montserrat?

Answer 16

ash and dust
NO LAVA

Question 17

what caused the most damage during the montserrat volcanic eruption?

Answer 17

pyroclastic flows

Question 18

what were the impacts of the montserrat volcanic eruption?
(6 points)

Answer 18

the capital was covered in 3m of ash and was abandoned
2/3 of houses were destroyed
3/4 of infrastructure was destroyed
the tourist industry collapsed
farmland was destroyed
young people emigrated to the UK leaving an ageing population

Question 19

how are volcanoes measured?

Answer 19

VEI
the volume of tephra, ash and pyroclastic flows
the height ash and tephra was ejected
the duration of the eruption
observations made

Question 20

how are volcanoes predicted?

Answer 20

seismometers detect ground tremors
volcanologists can see bulging, changing shape, tilting etc

Question 21

where do hot spots form?

Answer 21

the middle of a tectonic plate

Question 22

what causes a hot spot?

Answer 22

plumes of magma erupt on the ocean floor forming a volcano

Question 23

how does a hot spot make a chain of volcanic islands?

Answer 23

when the tectonic plates move, it carries the volcano with it allowing for the process to repeat and a new one to form