Chpt 1 Earth Structure And Plates

Question 1

What are the layers of the earth?

Answer 1

• The crust
• the mantle
• the outer core
• the inner core

Question 2

Describe the crust

Answer 2

Its solid rock that covers the surface of the earth. The continental crust is thicker than the oceanic crust. The crust is not all one piece - its divided into plates.

Question 3

Describe the mantle

Answer 3

Its under the crust. Its made of molten magma thats very hot and which flows in currents.

Question 4

Describe the core

Answer 4

Its the centre of the earth and is very hot- between 3,000 and 5,000 degrees. Mostly made of iron. Its solid int the centre. Its divided into inner and outer core.

Question 5

What is plate tectonics?

Answer 5

The study of plate movements and their effects- faulting, earthquakes, and volcanoes

Question 6

What are plate boundaries?

Answer 6

The edges where plates meet

Question 7

What is the small movements of the plates each year called?

Answer 7

Continental drift

Question 8

What happens when plates slide past each other?

Answer 8

Pressure builds up before plates move -> earthquakes

Question 9

What happens when plates separate?

Answer 9

Magma enters the cracks and forms volcanoes. Mid-ocean ridges are formed and new land is added. This forms islands- constructive plate boundary.

Question 10

What happens when plates collide?

Answer 10

The heavier plate sinks under the lighter plate. Pressure builds causing earthquakes, volcanoes and fold mountains - destructive plate boundary

Question 11

Give one example of plates sliding past each other

Answer 11

The pacific and north American plate

Question 12

Give five examples of plates separating

Answer 12

• north American and Eurasian plate
• Indo-Australian plate and the Antarctic plate
• south American plate and the African plate
• pacific and the nazca plate
• north American and the African plate

Question 13

Give our examples of plates colliding

Answer 13

• Eurasian and African plate
• Indian and Eurasian plate
• Eurasian and pacific plate
• nazca and south American plate

Question 14

What was the landmass that the plates were joined together in called?

Answer 14

Pangaea

Question 15

What causes the plates to move?

Answer 15

Convection currents in the mantle.

Question 16

Describe convection currents

Answer 16

As the magma is heated by the core, hot currents rise up in mantle and join or separate under the crust. Where the currents flow towards each other plates collide. Where the currents flow away from each other plates separate