Restless Earth Flashcards Preview

Geography physical and human > Restless Earth > Flashcards

Flashcards in Restless Earth Deck (24):
1

The four structures of the earth

Inner core
Outer core
Mantle
Crust

2

Three type of plate margins

Destructive margins
Constructive margins
Conservative margins

3

Destructive margin formation

Oceanic plate meets a continental plate
Denser plate is forced down and destroyed
Creates volcanos and ocean trenches

4

Constructive margin formation

Where two plates are moving away from each other
Magma rises from the mantle to fill gap and cools

5

Conservative margin formation

Where two plates are moving sides ways past each other
OR
Moving in the same direction but different speeds
Crust isn't created or destroyed

6

Formation of a fold mountain

Where tectonic plates collide the sedimentary rocks that have built up between them are folded and forced upwards
Happen at destructive plate margins

7

Uses of fold mountains

Farming- lower slopes are used to grow crops and steep slopes for terraced to make growing crops easier
HEP- steep sided mountains and ohh lakes make fold mountains ideal for generating hydroelectric power
Mining- these mountains contain metal ores and zig zag roads have been put in place in the sides to get to them
Tourism- used for skiing and snowboarding etc in winter and walkers come for the scenery in summer

8

Fold mountain case study

The Alps
12 million people
Collision of Africa and European plate

9

How people have adapted to the conditions in the Alps

Steep relief- goats are farmed to live in steep mountains and well adapted
Poor soils- animals graze in most high areas as the soil isn't good for growing crops
Limited communications- roads have been built over passes and tunnels for when roads are blocked by snow

10

Where are volcanos found?

Destructive plate margins where the oceanic plate goes under he continental plate as it is more dense
OR
Constructive margins where magma rises up into the gap created by plates moving a part foaming a volcano

11

What are the different types of volcanos ?

Composite volcanoes
Shield volcanoes

12

The features of a composite volcano

Steep sided
Layers of ash
Layers of lava
Vent

13

The features of a shield volcano

Low and flat
Runny lava
Layers of lava

14

How do scientists try to predict volcanic eruptions in advance?

Tiny earthquakes
Escaping gas
Changes in the shape of the volcano (bulges)

15

Volcanic eruption case study

Montserrat
1997
19 killed
Above a destructive plate margin where the Atlantic plate is being forced under the Caribbean plate

16

Primary and secondary impacts of Montserrat

Primary- large areas covered with volcanic material, pyroclastic flows ruining homes,vegetation destroyed and 19 people died
Secondary impacts- fires destined buildings, population declined, volcanic ash improved soil fertility

17

Immediate and long term responses of Montserrat

Immediate- people were evacuated to safe areas, shelters were built, temporary infrastructure built (roads)
Long wrk responses- a risk map to key people know where the exclusion zone is, the UK provided £41 billion, an observatory has been set up to try predict

18

What are supervolcanoes?

Much bigger than the standard volcano which develop at destructive plate margins or over the mantle (Yellowstone National Park)

19

Characteristics of a supervolcano

Flat
Cover a large area
Have a caldera

20

Consequences of a supervolcano

Thousands of cubic kilometres of rock and ash and laver
A thick cloud of super hated gas and ash which kills people, burns etc
A blackout from has
The ash burning fields and buildings

21

Where do earthquakes occur?

Destructive margins
Constructive margins
Conservative margins

22

How can earthquakes be measured?

The Richter scale- measures the amount of energy released by a seismometer
The Mercalli scale- measures effects of an earthquake by asking eyewitnesses

23

What are the primary and secondary effects of an earthquake?

Primary- deaths, injuries, damaged or destroyed buildings
Secondly- landslides, blocked roads, diseases spread from lack of clean water, aftershocks, fires, broken pipes

24

What is the case study for tsunamis?

Japan
2011