Tectonic Plates

Question 1

What are the four layers of the Earth?

Answer 1

Crust
Mantle
Outer Core
Inner Core

Question 2

What is the inner core?

Answer 2

Inner most part of the Earth, it’s a ball of solid iron and nickel that is 5000 degrees c

Question 3

What is the outer core?

Answer 3

At the centre of the Earth, the outer core is 3000 degrees c and has liquid properties, made from iron and nickel

Question 4

What’s the mantle?

Answer 4

Middle layer of the Earth which is made from semi-molten rock (magma), it’s up to 2800km thick

Question 5

What is the crust?

Answer 5

Outer layer of the Earth that ranges from about 0-60km thick

Question 6

What is the crust divided up into?

Answer 6

Tectonic plates

Question 7

What are the two types of crust?

Answer 7

Oceanic

Continental

Question 8

What’s the difference between oceanic and continental crust?

Answer 8

Oceanic Continental
Rock: Basalt Granite
Location: Under Oceans Land
Age: 1500 million + -200 million
Depth: 6-10km Up to 70km
Renewable: Yes No
Destroyed: Yes No

Question 9

What are the 4 plate boundaries?

Answer 9

Destructive
Constructive
Conservative
Collision

Question 10

What is a destructive plate margin? What forms?

Answer 10

An oceanic plate and a continental plate move towards eachother, causing the denser oceanic plate to sink into the mantle- destroying it
Volcanoes, Ocean Trenches

Question 11

What is a constructive plate margin? What forms?

Answer 11

Two plates move away from eachother, causing magma to rise from the mantle and fill the gap as it cools to make new crust
Volcanoes, Mid-Atlantic Ridge

Question 12

What’s a conservative plate margin? What forms?

Answer 12

Two plates move sideways past eachother, they can stick causing pressure to build up, when the pressure is suddenly released earthquakes occur
Earthquakes

Question 13

What’s a collision plate margin?

Answer 13

Two continental plates move towards eachother, and because they can’t be destroyed they ‘buckle’ upwards creating fold mountains
Fold mountains

Question 14

What are convection currents?

Answer 14

Movements within the Earth’s mantle caused by the heat of the core

Question 15

How do convection currents work?

Answer 15

Heat source in the form of radioactive decay in the Earth’s core heats the semi molten rock in the mantle
This causes it to rise as it is less dense
When it reaches the top of the mantle, it spreads out which moves the plate above it
The rock then cools, becomes denser and sinks back down
The process is constantly repeated

Question 16

What evidence is there for continental drift?

Answer 16

Fossils of the same species found all over the world
Jigsaw- N and S America fit into Africa
Same rock types can be found across the world

Question 17

What did the Earth look like 250 million years ago? Why did it change?

Answer 17

A supercontinent, Pangaea

Continental drift