Tectonic Plates

Question 1

What are convection currents?

Answer 1

A type of circular movement caused by heating and cooling

Question 2

How do convection currents work?

Answer 2

• the core is extremely hot and heated the magma above in the mantle

• the magma is heated up and rises to the surface, it then cools down when it hits the crust

• the magma will then either be pushed to the side or if the crust is thin enough it will break through the crust, causing a volcanic eruption

• while going to the side it gets cooler and cooler and eventually sinks back down

• if the convection currents are moving anti-clockwise direction the plate above will move to the left

• if the convection currents are moving in a clockwise direction the plate above will move to the right

Question 3

Five points about the oceanic crust

Answer 3

• sits under oceans

• thinner than continental crust

• denser than continental crust

• can be renewed and destroyed

Question 4

Four points about the continental crust

Answer 4

• sits under land

• thicker than oceanic crust

• less dense than oceanic crust

• cannot be renewed and destroyed

Question 5

What are plate boundaries?

Answer 5

Where two or more tectonic plates collide

Question 6

What are divergent (constructive) plate boundaries?

Answer 6

Where the plates move away from each other, causing magma to rise from beneath the ground and through the crack, this cools and creates new oceanic crust causing earthquakes.

Question 7

What are convergent (destructive) plate boundaries?

Answer 7

Where oceanic and continental plates move towards each other, the oceanic plate is sub-ducted (goes under) beneath the continental plate (because the oceanic plate is denser which means more full and heavy). This creates an oceanic trench. The plates cause friction by rubbing against each other which results in earthquakes, this friction and heat from the mantle melts the oceanic plate. The magma rises to create a volcano with a violent eruption

Question 8

What are conservative (transform) plate boundaries?

Answer 8

Where two plates try to slide past one another, they stick or get jammed together in the process causing huge amounts of pressure to build up. Eventually, as the plates are freed, the pressure is released causing violent earthquakes