Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Geography > Tectonics > Flashcards

Tectonics Flashcards

1
Q

Crust

A

Thinnest layer of Earth

Between 5 and 70km thick

Solid rock broken up into pieces called tectonic plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Mantle

A

Thickest layer 2900km

Moves slow big circles caused by convection currents

1000 degrees near crust
3700 degrees near outer core

Semi-molten (semi-liquid rock)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Outer core

A

Semi liquid iron

3700 - 5000 degrees

2300km thick

Iron here is liquid and magnetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Inner core

A

1250km thick

Hottest part of earth

5000 degrees

Made up or iron and nickel under pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Wegener’s theory

A

Jigsaw fit

All the countries of the world were once joined together and then had been moved apart

Called Pangea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Evidence for Continental Drift

A

Fossil evidence

Fossils found in countries so far away it would be impossible for the animal to get there unless all the countries of the World were connected

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Convection currents

A

movements of volcanic rock in mantle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Palaeomagnetism

A

the study of the Earth’s magnetic field preserved in rocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the tectonic plate

A

Pacific plate
North American plate
South American plate
Eurasion plate
Cocos plate
African plate
Nazca plate
Indo-australian plate
Juan de Fuca playe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Subduction zone

A

where one plate is forced downwards below another plate and grinds past it causing huge amounts of friction and heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Destructive plate boundary

A

where two plates are moving towards each other

continental crust | oceanic crust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Fold mountains

A

large mountain ranges formed by the collision and ‘folding’ of two plates as they plates continually push into one another.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Ocean trench

A

a particularly deep point of the ocean bed where the oceanic and continental crust have dragged each other downwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Plate boundary

A

where two very large crustal plates meet on the earth’s surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Oceanic crust

A

plate that is made up of more dense rock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Composite volcano

A

A very steep volcano formed at a destructive boundary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Why earthquakes are often found at plate boundaries

A

Most earthquakes occur due to the movement and interaction of tectonic plates

Tectonic plates constantly shift and collide with one another creating eargtquakes at their boundaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How are volcanoes found at divergent plate boundaries

A

Divergent boundaries - occurs when 2 tectonic plates moving away from each other

As they separate magma from the mantle can rise to fill the gap creating new crust and forming volcanic ridge

19
Q

How are volcanoes formed at convergent boundaries

A

Occur when 2 tectonic plates are moving towards each other

If 1 plate is denser than the other it can sink beneath the other in a process called subduction

This subduction can cause sinking plate to melt leading to the formation of a volcanic arc

20
Q

Why are volcanoes rarely formed at transform boundaries

A

There is little or no magma available at the plate boundary

21
Q

Why are convection currents important

Weather

A

Convection currents in the Earth’s atmosphere are responsible for creating weather patterns such as thunderstorms, tornados and hurricanes

Understanding these currents are important for predicting weather and preparing for severe weather events

22
Q

What forms at convergent collision boundaries

A

Fold mountains

Volcanoes

Tsunamis

Composite volcano

Earthquakes

23
Q

What forms at conservative boundary

A

Earthquakes

24
Q

What is formed at divergent plate boundary

A

Shield volcano

Can cause tsunamis

Yes but frequent and small earthquakes

25
Q

What happens at conservative plate boundaries

A

fault lines will be formed

These are plate boundaries where two plate are either slipping past each other in opposite directions or at different rates in the same direction

26
Q

What happens at divergent plate boundary

A

the plates move apart from one another

When this happens the magma from the mantle rises up to make new crust

27
Q

Causes of Montserrat volcanic eruption

A

on a destructive plate margin

The 2 plates converge due to convection currents

As the two plates merge the oceanic plate is sub-ducted under the continental plate

As its forced down pressure increases which triggers earthquakes

heat produced by friction melts the descending crust to form molten magma

28
Q

Impacts of Montserrat volcanic eruption

A

2/3 of the island became covered in ash

Ash polluted air increasing breathing difficulties

50% population evacuated north of the island into temporary shelters

Forest fires and tsunamis were caused by the pyroclastic flows

The only airport was closed

29
Q

Causes of Haiti earthquake

A
30
Q

Impacts of Haiti earthquake

A

Haiti debt $4.5Bn

50% population in debt earn less than $1 a day

70% population unemployed

For every 1 person Haiti’s government has $450 of debt

31
Q

Conservative fault

A

Plates slip past each other

32
Q

Causes of Haiti earthquake

A

Happened on the caribbean tectonic plate where earthquakes often occur

The conservative fault caused friction between the North American Plate and the Caribbean Plate which lead to the earthquake

33
Q

Why were the impacts of Haiti earthquake so bad

A

Poorly built buildings fell on people and trapped them

High magnitude

Haiti was near the epicentre

34
Q

Causes of a tsunami in example location

2004 indonesia

A

9.1 magnitude earthquake off the coast of country

Caused as epicentre was located in the Indian Ocean on the ocean floor which is where tsunamis are most powerful

35
Q

Impacts of Indian Ocean Tsunami of 2004

A

Killed 230,000 people

1.7 million people homeless

Just under $10 billion in debt

179,000 buildings and homes destroyed

170,000 people died 20-30 minutes after tsunami came

36
Q

Constructive

A

Divergent

37
Q

Destructive

A

Convergent

38
Q

Conservative

A

Transform

39
Q

Epicentre

A

The point directly above the centre of the earthquake on the earth’s surface

40
Q

Focus

A

Where the pressure is released underground

41
Q

2 major categories tectonic plates

A

Continental

Oceanic

42
Q

What subducts in a convergent plate boundary

A

Oceanic crust subducts under land crust

Because oceanic crust is denser

43
Q

What subducts at transfom plate boundary

A

No subduction when they meet

Geography (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions