Plate tectonics

Question 1

Lithosphere

Answer 1

• Crust and upper mantle, where tectonic plates are formed

Question 2

Crust

Answer 2

Two types;

• Oceanic
• Continental

Question 3

Oceanic

Answer 3

• Broken layer of basaltic rocks = SIMA
• Made from SILICA and MAGNESIUM
• Thinner
• Younger
• Heavy/denser

Question 4

Continental

Answer 4

• Mainly granitic rock = SIAL
• Made from SILICA and ALUMINIUM
• Thicker
• Older
• Light/ less dense

Question 5

Upper mantle

Answer 5

Rocks here are solid and sit on the asthenosphere

Question 6

SIMA

Answer 6

• Lower layer of the Earth’s crust

- Found beneath oceans

Question 7

SIAL

Answer 7

• Upper layer of the Earth’s crust
• Forms continental land masses
• Thicker and less dense as SIMA

Question 8

Asthenosphere

Answer 8

• Layer of soft, plastic-like rock
• Moves very slowly
• Carrying the lithosphere on top

Question 9

Mantle

Answer 9

• Widest section of the earth = 2900km thick
• Great heat and pressure
• Silicate rocks are in thick, liquid state = denser with depth

Question 10

Outer core

Answer 10

• Mainly made up of iron

- Semi-liquid

Question 11

Inner core

Answer 11

• Mainly made up of an iron-nickel alloy
• Soild
• Hottest part = 5000 degrees
• 4 times as dense as crust