Convection Currents Flashcards
How much do tectonic plates move every year
2.5cm (They move at the speed in which a fingernail grows)
What is the earths crust made of
Tectonic Plates
What do continetal plates make up
Continents
What do Oceanic plates make up
Ocean Floors
Which is more dense a continetal plate or an oceanic plate
Oceanic
A Continetal plate is
Lighter and more airy than an oceanic plate
What is Subduction
When the more dense Oceanic Plate gets pushed under the lighter continetal plate
What happens when a continetal and oceanic plate meet
Subduction
Where do Convection Currents exist
In the Mantle
What are convection currents
When rock in the mantle heats up from the core it rises to the crust and it cools and then falls back down; this is what pushes the plates apart.
Explain RIdge push
Magma rises as the plates move apart. The magma cools to form new plate material. As it cools It becomes denser and slides down away from the ridge. This causes other plates to move away from each other.
Slab pull
The denser plate sinks back into the mantle under the influence of gravity. It pulls the rest of the plate along behind it.
Name 2 Reasons why plates can move more than 2.5cm a year
Ridge Push and Slab Pull
