Types Of Plate Margin

Question 1

Constructive plate margins

Answer 1

Occurs when two plates are moving apart (diverging)
1 - the mantle is under pressure and when plates move apart the pressure is released at the margin
2 - this causes mantle to melt, producing magma
3 - the magma is less dense than the plates above so it rises and can erupt to form a volcano
4 - build up of pressure causes plates to crack and form a fault line causing an earthquake

Question 2

Landforms created at a constructive plate margin

Answer 2

Ocean Ridge - where diverging plates are underwater, an ocean ridge forms . Underwater volcanoes erupt along mid ocean ridges and they can build up to be above sea level

Rift Valley - where plates diverge beneath land, rising magma causes the continental crust to fracture causing fault lines. As the plates keep moving apart the crust between two faults drops down to form a rift valley

Question 3

Destructive plate margins - OCEANIC VS CONTINENTAL

Answer 3

Plates are moving towards each other
The more dense oceanic crust is forced under the less dense continental crust (subduction)
The oceanic crust is heated by friction and contact with the upper mantle that melts it into magma
The magma is less dense than the continental crust above and will rise back to the surface to form volcanoes
As one plates moves under the other it can get stuck causing pressure to build and when released this causes earthquake

FORMS DEAP SEA TRENCH AND FOLD MOUNTAIN

Question 4

Destructive Plate margin - OCEANIC V OCEANIC

Answer 4

Denser of the two plates will be subducted forming a deep sea trench and triggering earthquakes and volcanic eruptions

VOLCANIC ERUPTIONS UNDERWATER CAN FORM ISLAND ARCS (cluster of islands on a curved line)

Question 5

Destructive plate margins - CONTINENTAL VS CONTINENTAL

Answer 5

Neither plate is subducted so no volcanoes are formed but pressure builds that can cause earthquakes

FOLD MOUNTAINS form when continental crusts converge

Question 6

Conservative Plate Margin

Answer 6

Two plates are moving past each other
Two plates get locked together in places and pressure builds causing plate to crack and form fault lines releasing energy as an earthquake

NO VOLCANOES

Question 7

Magma Plumes

Answer 7

A magma plume is a vertical column of extra hot magma that rises from the mantle that causes intense volcanic activity that is not near plate margins. The ground above is called a hot spot and volcanoes can form above the magma plume
The chain of islands that makes up Hawaii was formed by a magma plume