Hotspot

Question 1

Volcano distribution

Answer 1

Most occur along plate boundaries - destructive and constructive

Some occur at hotspots

Question 2

Example of Hawaii hotspots

Answer 2

Islands are entirely of volcanic origin.
Formed in Pacific Ocean.
3,200km away from nearest Pb.
Stationary hotspots generate convection currents within asthenosphere.
Causes magma to rise towards crust and spread before cooking and sinking.
Causing volcano.
As convection currents in mantle move plates away from heatsource - volcano to become extinct.
New crust at hotspot with form volcano.
Process continues until long chain of volcanic islands form.

Question 3

Convection currents and plate movements

Answer 3

Magma rises up through asthenosphere towards crust.
It spreads. Cools. Sinks.
Causing crust plates to move as they “float” on denser material of asthenosphere.
New crust formed at constructive Pb.
Older crust destroyed at destructive Pb.
No creation/ destruction at conservative

Question 4

What type of volcanoes at in Hawaii?

Answer 4

Basaltic shield volcanoes.

Build up over time to form island.

Question 5

Older/ newest volcanoes in Hawaii

Answer 5

Newest ones are nearest hotspot - most volcanically active.

Oldest ones further away from hotspot - move 10cm annually.

These will have become eroded by wages to form flat tip sea mounts - guyots