10) Structure Of The Earth

Question 1

Name the 5 layers of the earth (5)

Answer 1

• outer Crust
• inner mantle
• outer mantle
• liquid outer core
• solid inner core

Question 2

Try your best to give the depth of the layers (7)

Answer 2

• crust 0-35
• mantle 0-2 890 km
  • uppermost 35-60 km
  • upper 210-270 km
  • lower 660-2 890 km
  -liquid outer core 2 890- 5 150 km
• solid outer core 5 150 - 6 360 km

Question 3

How do we get our understanding of the earths structure (4)

Answer 3

• observations of the topography
• observations of rock formations
• experiements done by scientists
• samples brought to the surface but volcanoes/activity

Question 4

Which layer is the crust (1)

Answer 4

The outer layer

Question 5

Discuss the continental crust (3)

Answer 5

• the thick continental crust
• it’s not continuous around the earth
• it’s made up of silicate rock e.g. granite

Question 6

Discuss the oceanic floor (3)

Answer 6

• the thin layer of the crust
• a continues layer around the earth
• its made uo of hard indigenous rovk e.g. basalt

Question 7

Give another word for continental + oceanic crust (2)

Answer 7

• sial

- sima

Question 8

When was the crust made(2)

Answer 8

• most rocks are + 100 mil years ago
• the oldest minerals found are 4.4 bil years ago
• indicating the crust is at least 4.4 bil years old

Question 9

Which layer is the thickest (1)

Answer 9

The mantle

Question 10

What is the mantle divide into (2)

Answer 10

• into the upper mantle and lower mantle

Question 11

What is the transition zone (1)

Answer 11

The seperated area between the 2 mantles

Question 12

What is the mantle made up of (3)

Answer 12

• of silicate rock
  • iron
  • magnesium

Question 13

Why is the mantle thick flowing lava (2)

Answer 13

• the high temperatures cause thick flowing magma

- the movement of the magma can be seen in the movement of plates

Question 14

Explain the mantle’s density (2)

Answer 14

• there is an intense increase of pressure the deeper into the mantle you go
• lower mantle is denser than the upper mantle

Question 15

What is the core divided into (2)

Answer 15

• liquid inner core

- solid outer core

Question 16

What is the radius of the inner core (1)

Answer 16

3 400 km

Question 17

What is the inner core mainly made of (5)

Answer 17

• iron
• gold
• nickle
• traces of minerals and platinum

Question 18

Why is the core seperated (3)

Answer 18

• It is believed in the early stagevof the earths development, melting caused denser substances to sink to the center
• while the less denser substances move to the crust
• 4.5 mil years ago

Question 19

What is the outer core made of (2)

Answer 19

A compound of iron, mixed with nickle and ligter elements

Question 20

Explain the movement of the crust:
•collide
•move apart
•one up + one down
• slide

Answer 20

Collide:

• pressure forces the plates upwards
• they fold, and firm mountains

Move Apart:

• magma rises through the cracks
• magma forms new rock when it solidifys
• this is how volcanoes are formed

One up + one down:

• one plate is forced below the under
• so one is up and one is down
• they form block mountains + rift valleys

Slide:

• the plates slide against eachother
• causes earthquakes