Flashcards
Tectonic Plates
Flashcards do conjunto (13)
- 1Continental crust is...... thicker and less dense
- 2Oceanic crust is...... thinner and more dense
- 3Why do tectonic plates shift?Because the rock in the mantle underneath them is moving
- 4What are 'boundaries' or 'plate margins'?Locations where plates meet
- 5Name the three types of plate margins.1) Destructive margins
2) Constructive margins
3) Conservative margins - 6What is a Destructive margin and give an example.Destructive margins are where two plates are moving towards each other, e.g along the east coast of Japan
- 7What happens when a Destructive oceanic plate meets a continental plate?The denser oceanic plate is forced down into the mantle and destroyed.
- 8What is created by a Destructive oceanic plate meeting a continental plate?Volcanoes and oceanic trenches
- 9What happens when two Destructive continental plates meet?They smash together, but no crust is destroyed
- 10What is a Constructive margin and give an example.Where two plates are moving away from each other, e.g at the mid-Atlantic ridge
- 11What happens when Constructive margins move away from each other?Magma rises from the mantle and it fills the gap, cooling to form new crust
- 12What is a Conservative margin and and give an example.Where two plates are moving sideways past each other, or moving in the same direction but at different speeds, e.g the west coast of the USA
- 13What does a Conservative margin do the the crust?Nothing, crust isn't created or destroyed