Brainscape's Knowledge GenomeTM

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


See full index

YEAR 9 - Geography > Plate Tectonics > Flashcards

Plate Tectonics Flashcards

You may prefer our related Brainscape-certified flashcards:
U.S. Geography flashcards World Geography flashcards
1
Q

Name the 4 basic features of the theory of plate tectonics?

A

Lithosphere is divided into plates like a jigsaw
The plates move in relation to each other
Plates are created from molten material (magma) coming to the surface and plates are destroyed elsewhere
Plates are made by different types of rock

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

What is the distance of the Lithosphere and the Asthenosphere from the surface?

A

1-100 km and 1-300 km

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

What was the distance in km from the surface from the mantle?

A

600-2900 km

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

What was the distance in km from the surface of the outer and inner core?

A

5100,6375

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

Describe the Core

A

Very dense, very hot, inner core solid, outer core liquid, source of geothermic heat

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

Describe the mantle

A

Solid, dense, heat from the core moved through it part of it (asthenosphere) is neither solid nor liquid plastic

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

Define the crust

A

Outermost layer, low density, easily folded+fractured,very variable in thickness

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

Define the lithosphere

A

Crust+upper part of mantle, low density, relatively brittle, separate plates, 2 types of lithosphere- oceanic and continental,plates can be one or both, very thin under the oceans, very thick under continents

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

Define the Asthenosphere

A

Part upper mantle,higher density than lithosphere, liquid plastic, it can move/deform has convection currents which drives the movements of plates. Where convections diverge lithosphere is created when converge it is destroyed

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

Name some features of the oceanic plate

A

Basalt rock, thin 1->10 km, dense, younger, more active, more flexible

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

Name the features of an continental plate

A

Granite rock, thicker 10->100km, less dense, older,less active, relatively flexible

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

What is converging ?

A

When somethings are moving together

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

What is diverging?

A

When some things are moving apart

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

What defines what happens at the plate boundaries?

A

The movements of the plates

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

What occurs at plate boundaries?

A

Earthquakes

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

Where are volcanoes in relation to the plates?

A

Mostly along boundaries, but not all. Most concentration around the Pacific Ocean called the “ring of fire”

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

Describe a constructive margin

A

Divergent plates: new lithosphere being created

- magma rising

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

Name an example of the plates in a constructive margin

A

North American + Eurasian plates

Atlantic Ocean

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Are earthquakes created at a constructive margin?

A

Yes- generally low magnitude frequent caused by magma rising

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are there volcanoes at constructive margins?

A

Yes-new crust created, effusive (non-explosive) produces lots of lava

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the earths crust officially called?

A

Lithosphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe a destructive subduction zone margin

A

Convergent plates: oceanic+continental crust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Give an example of a destructible subduction zone

A 
Nazca plate (o)+ S.American plate (c)
W.Coast of S.America
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Are here earthquakes at a destructive subduction zone?

A

Yes- high/v.high magnitude most of them highest recorded earthquakes,infrequent
(Chile 1960,9.5)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Are there volcanoes at destructive subduction zones?

A

Yes-v.explosive produces lots of ash,pyroclastics,gas etc.

Little lava ,often blows the top off mountain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe an destructive island arc

A

Convergent plates, involves 2 oceanic plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Give an example if an island arc boundary

A

Caribbean+N.America plates

Both oceanic in the Antilles (W.Indies)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the earthquakes and volcanoes at island arcs compared to subduction zones?

A

They are same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Describe a collision zone margin

A

Convergent plates: 2 continental plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Give an example of a collision zone plate margin

A

Indian+Eurasian plates

Both continental in N.Indian (Himalayas)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Are there earthquakes at collision zones?

A

Yes- any magnitude but the highest, higher the magnitude the less frequent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Are there volcanoes at collision zones?

A

Yes- not explosive,produces lava and fire fountains although very little activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Describe a constructive plate margin

A

Two plates sliding side by side- any type of plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Give an example of a constructive margin

A

N.American+Pacific plates

California (San Andreas Fault)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Are there earthquakes at constructive plate margins?

A

Yes-very frequent, but occasionally high magnitude such as 1906 San Francisco earthquake at 8.0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Are there any volcanoes at constructive plate margins?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Describe a oceanic hot spot

A

Plume of magma very close to the surface in the centre of an oceanic plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Give an example of an oceanic hot spot

A

Hawaiian Islands in the centre of the pacific plate

Oceanic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Are there earthquakes at oceanic hot spots?

A

Yes- due to rising magma but low magnitude and infrequent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Do volcanoes occur at oceanic hot spots?

A

Yes- produces very large volume of “running lava” continuous activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Describe a continental hot spot

A

Plume of magma very close to the surface in the centre of a continental plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Give an example of an continental hot spot

A

Yellowstone Park

Centre of the N.American plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Do earthquakes occur at continental hot spots?

A

Yes- infrequent and moderate magnitude (5-6.5)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Do volcanoes occur at continental plate boundaries?

A

Yes- very infrequent, but massive, super volcanoes producing different types of lava some runny some not

45
Q

Where are subduction zones found?

A

Constructive and destructive plate margins

E.g West coast of South America

46
Q

What does the oceanic plate do at a subduction zone?

A

As it is denser so it sinks beneath the continental plate this is called subduction

47
Q

What does the oceanic plate do to the seabed to form what?

A

Ocean trench

48
Q

What does the oceanic plate take down with it in a subduction zone and what does it do?

A

Sea water and it lowers the melting point of the subduction point

49
Q

Do the two plates in a subduction plate slide by each other easily and what happens?

A

They do not slide past easily and when it becomes too great there is a sudden jerk which causes an earthquake

50
Q

What is the place where the melting occurs?

A

Benioff Zone

51
Q

What happens to the continental plate in a subduction zone?

A

The continental plate is less dense and crumples forming fold mountains

52
Q

What happens when the oceanic plate sinks?

A

It causes the oceanic plate to melts

53
Q

What do the molten rocks form? And what are the properties of that thing?

A

Plutons, they rise through the continental plate

The new magma is very light and full of gas

54
Q

What do plutons create when they reach the surface? And what kind of them are they?

A

Volcanoes- they are very violent as there is so much gas

55
Q

What happens when a pluton solidifies?

A

They form huge masses of granite which may get exposed when the overlaying rocks are eroded away

56
Q

Name the first stage of a constructive plate margin

A

Convection currents in the asthenosphere

57
Q

Name the second stage of a constructive plate margin

A

Tension causes the lithosphere to stretch and thin magma pushes up and causes the lithosphere to bend upwards

58
Q

Name the third stage of a constructive plate margin

A

The lithosphere eventually fractures along two lines and part of it sinks creating a rift. Magma reaches the surface through the fractures

59
Q

Name the fourth stage of a constructive plate margin

A

The lithosphere is now wider. The magma stops rising and lava forms. The process is repeated many times and the ocean gets wider and wider

60
Q

What happens when the gap in the constructive plate margin widens?

A

Magma reaches the surface and forms new rock. Usually starts beneath land but eventually a ocean basin forms with the land moving away on either side

61
Q

Give an example of an ocean basin

A

Mid-Atlantic Ridge

62
Q

Where is the northernmost part of the Mid-Atlantic Ridge?

A

Iceland

63
Q

Does volcanic activity and earthquakes occur on the Mid-Atlantic Rift?

A

Yes- volcanoes: non explosive (effusive)

Yes-Earthquakes: low magnitude events

64
Q

What are the main features of a subduction plate margin?

A

Ocean trench,fold mountains,earthquakes (highest mag.)

Volcanoes: lava,pyroclastic flows,ash,Lahars

65
Q

What type of lava is produced at a volcano at a subduction zone?

A

Very thick (viscous), non-runny, travels only short distances

66
Q

What are volcanoes like at a subduction zone?

A

Very explosive,often destroy part of the mountain

67
Q

What are pyroclastic flows like at subduction zones?

A

Mass of gas,ash,large lumps of lava travelling at up to 200km/h at up to 200C

68
Q

What is ash?

A

Pulverised rock from the mountain, can be up to 20 km high

69
Q

What are Lahars?

A

Volcanic mudflows formed when ash mixes with water ( melting ice cap, or a rain storm) moving at up to 100km/h

70
Q

How is a island arc formed?

A

One oceanic plate sub ducts under another oceanic plate. The non-subducting plate doesn’t fold. Volcanoes occur forming a curving line of Islands e.g W.Indies

71
Q

How is a collision zone margin formed?

A

Starts as a subduction zone and slowly the ocean basin which is a oceanic lithosphere (ol) becomes narrower. Eventually there is no (ol) left and 2 (cl) collide and crumple forming fold mountains.

72
Q

Do earthquakes and volcanoes occur at collision zones?

A

A lot of activity when the subduction is occurring but as it stops far less volcanoes more earthquakes including v.high magnitude

73
Q

Give an example of a collision zone

A

Himalayas and the Tibetan plateau

74
Q

What can a collision margin create?

A

A depression. E.g Ganges depression

75
Q

What happens at a conservative plate margin?

A

Two plates slide past each other but there is no vertical moments

76
Q

Give an example of a conservative plate margin

A

San Andreas fault line

77
Q

What are the two plates at the San Andreas fault line and why is there friction?

A

N.American plate and the Pacific plate. They travel the same direction but the N.American plate travels slower and creates the illusion it is travelling in the opposite direction

78
Q

What magnitudes are earthquakes at hot spots?

A

Low magnitude

79
Q

How are volcanoes created at hot spots?

A

A magma plume is very close to the thin lithosphere

80
Q

What is volcanic activity like on the big island in Hawaii?

A

Continuos but not explosive, fire fountains (clumps of lava thrown into the air) and fast-flowing lava

81
Q

Does the Hawaiian hot spot move over time?

A

No- the Pacific plate moves NW, looks like it moves SE. Due to the location volcanic activity only occurs on the big island. The northern islands are smaller due to thermal contraction,erosion ams landslides

82
Q

What are the two main causes of earthquakes?

A

Movement of crust at fault lines e.g plate boundary (large mag.)
Movements of magma under lithosphere (smaller mag.)

83
Q

What are the 4 types of seismic waves?

A

P,S,L,R waves

84
Q

What do movements in plates cause?

A

Seismic waves

85
Q

What is the point where a earthquake occurs?

A

Focus

86
Q

What are earthquakes measured by?

A

Seismometer

87
Q

What is a seismometer connected to and what does it produce?

A

Seismograph and it produces a time-based trace of the movement.

88
Q

What is the trace from a seismograph called?

A

Seismogram

89
Q

What can be used to locate the epicentre of an earthquake?

A

P and S waves travel at different rates

90
Q

What is the formula to locate the distance from an earthquake?

A

Time in seconds between the arrival of the P and S waves x 8
= distance in km to the epicentre (approx.)

91
Q

What is the minimal amount of seismometers needed to pinpoint a epicentre?

A

3

92
Q

What are the two scales for earthquakes called?

A

Richter and Mercalli

93
Q

An increase of 1 on the Richter scale = how much more energy released ?

A

30x

94
Q

What is the Richter scale based on?

A

The amount of energy released

95
Q

Is the Richter scale finite or infinite?

A

Infinite

96
Q

What is the Mercalli scale based on?

A

Observation of damage that occurs

97
Q

Is the Mercalli scale finite or infinite?

A

Finite, 1 to 12

98
Q

Are the two scales for earthquakes related and if so to what use?

A

Yes- to asses possible impact which is valuable in formation for rescuers etc.

99
Q

What was the date of the Kobe Earthquake?

A

17th January 1995

100
Q

Why was the Kobe earthquake happening at 5:46 significant?

A

People are travelling in their cars (rush hour), more death as more people

101
Q

What was the magnitude and duration of the Kobe earthquake?

A

7.2 and it lasts for 20 seconds

102
Q

Name the primary impacts at the Kobe earthquake

A

200,000 buildings collapsed, many trains derailed

1km of Hanshin Expressway and 130km of bullet train bridges collapsed. 120 of 150 quays in main port destroyed

103
Q

What were the two plates involved in the Kobe Earthquake?

A

Philippine plate and Eurasian plate

104
Q

Secondary effects of the Kobe earthquake

A

Electricity/gas/water supplies disrupted, fires destroyed 7500 houses from electricity mains and broken gas pipes. Gridlock roads,delayed emergency services.230,000 made homeless
716 aftershocks, Mitsubishi and Panasonic closed

105
Q

What happened at the Kobe earthquake?

A

Philippine plate is forced down on contact with the Eurasian plate. This is issued a very big earthquake after a long time of friction etc.

106
Q

What were the long term effects of the Kobe earthquake?

A

Central areas and commercial rebuilt but worst affected had little rebuilding.
New buildings are made earthquake proof by concrete frames,reinforcing bars and steel frames
No buildings built on clay as liquefies causing collapse

107
Q

How are fold mountains formed?

A

Two continental plates collide with enough force to crumple the lithosphere

108
Q

How can a volcano help a person who lives close to them?

A

Farming as rich land from volcano
Minerals and rocks can be used or sold
Create jobs for the tourism created

109
Q

What type of place would be effected by a volcano?

A

Ski resort

YEAR 9 - Geography (6 decks)

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