Tectonic Hazards - 1.2.3 Plate Margins & Volcanoes

Question 1

Tell me about constructive plate margins.

Answer 1

Plates move apart (diverge).
Convection currents diverge and create a gap between the plates.
Magma rises to fill the gap.

Question 1

Tell me about destructive plate margins.

Answer 1

Oceanic plate slide underneath contintential plate.
Plate surfaces are not smooth so pressure builds -> plates can’t take the pressure and causes them to slip. Earthquakes occur.

Question 1

Tell me about conservative plate margins.

Answer 1

Plates are sliding past eachother.
Plates are not smooth so pressure builds up, plates can’t take the pressure and so suddenly slide past causing earthquakes.

Question 2

What are the three different types of plate margins?

Answer 2

Conservative
Constructive
Destructive

Question 3

Which plate margin do volcanoes form?

Answer 3

Volcanoes form at constructive and destructive plate margin where there is a gap in the Earth’s crust and the magma rises to fill the gap.

Question 4

What are hot spots?

Answer 4

Hot spots happens when the hottest part of the mantle finds a crust’s weakness and weakens the crust until the magma reaches the surface.

Question 5

Characteristics of volcanoes at destructive plate margins.

Answer 5

Highly explosive
Produce a lot of gas
Produce a lot of lava

Question 6

What are pyroclastic flows?

Answer 6

Currents of hot ash that can move downhill at speeds up to 500Km/h during an eruption.
They can reach up to 1000°C and cover 30km from the volcano.