The Dynamic Earth

Question 1

Outer section of Earth (crust & upper mantle are called)

Answer 1

Lithosphere

Question 2

Average plate movement speed

Answer 2

5-10 cm per year

Question 3

Theory proposed by Alfred Wegener

Answer 3

Continental drift, all continents once together but drifted apart

Question 4

Evidence for continental drift

Answer 4

• Land masses fit together
• Similar fossil records across multiple continent
• Magnetic alignment of rocks

Question 5

How has Continental drift affected Fauna and Flora

Answer 5

If a continent is separated for a large period of time it allows for unique flora and fauna to evolve in unique conditions

Question 6

Define subduction

Answer 6

1 plate moves under another due to a convergent boundary.

Question 7

The mantle is apart of which inner section

Answer 7

Asthenosphere

Question 8

What causes convection currents

Answer 8

Hot less dense magma rises while cooler magma sinks and is heated by the earth’s core. This creates a current moving in a cyclical motion

Question 9

Oceanic or Continental:

Which is denser

Answer 9

Oceanic

Question 10

Oceanic or Continental:

Which is older

Answer 10

Continental

Question 11

Oceanic or Continental:

Which has a higher basalt content

Answer 11

Oceanic

Question 12

Oceanic or Continental:

Which is more likely to be subducted

Answer 12

Oceanic

Question 13

Divergent boundaries

Answer 13

Involves spreading, creates ridges, constructive and creates volcanic activity

Question 14

Convergent boundries

Answer 14

Involves subduction, creates trenches, destructive and creates volcanic activity

Question 15

Transform boundries

Answer 15

Involves lateral sliding, conservative and creates earthquakes

Question 16

Explain magnetic stripping

Answer 16

Magnetic striping is produced from the generation of magma at mid-ocean ridges during alternating periods of the Earth’s magnetic field

Question 17

Explain sea floor spreading

Answer 17

As new sea floor is created from divergent boundary the older rock is pushed away.

Question 18

Why do convergent boundaries create more explosive volcanoes than divergent boundaries

Answer 18

Convergent boundaries push more rock downwards creating greater pressure and greater force from the volcanoes.

Question 19

Describe the process of folding

Answer 19

The forces on the layers are so large that layers of rocks bend and crumple without breaking and instead fold in on itself

Question 20

Difference between anticline and syncline

Answer 20

Anticlines go upwards while synclines bend downwards

Question 21

How are horsts formed

Answer 21

A block of land is pushed upwards by the forces below

Question 22

Describe transform faults

Answer 22

A small crack caused by two plates sliding past each other

Question 23

Describe reverse faults

Answer 23

Rocks have been forced upwards due to the subducting plates pushing both sides together

Question 24

Describe normal faults

Answer 24

Rocks slip downwards due to the rocks being stretched out