Restless Earth - Tectonics

Question 1

What happens at a constructive plate boundary

Answer 1

Plates move apart due to convection currents (this allows magma to rise through the gaps and cool to form shield volcanoes)
volcanic islands (e.g. Surtsey, Iceland) are formed.
Shield volcanoes and earthquakes occur here

Question 2

What happens at a destructive plate boundary?

Answer 2

Composite (Cone) Volcanoes (E.g. Mount St. Helens) and Earthquakes occur here
Tectonic plates move together
Oceanic crust sinks under continental crust and melts in the subduction zone
Energy may be released as an earthquake
Molten magma may rise up to cause a volcanic eruption
Continental crust is crumpled to form fold mountains

Question 3

What happens at a conservative plate boundary?

Answer 3

The plates slide past each other
Pressure builds up between the two plates until the jerk past each other
The two plates jerking past each other causes an earthquake

Question 4

What happens at a collisional plate boundary?

Answer 4

Two plates of similar densities move together (continental + continental) (oceanic + oceanic)
This causes the rock to be forced upwards to form fold mountains (e.g. The Alps)

Question 5

How many plate boundary types are there?

Answer 5

4.

Constructive, Destructive, Conservative, Collisional