General Flashcards

You may prefer our related Brainscape-certified flashcards:
0
Q

Wegener’s Evidence?

A

The fit of Africa and South America. - gaps due to erosion and overlaps due to deposition.
Glaciation: only makes sense if continents were together.
Measosauras fossils: found in Africa and South America. Gap to large to swim and no land bridges.

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

What is Alfred Wegener’s theory of continental drift?

A

All continents were joined together called Pangea.
Then split into 2 continents Laurasia, and Gondwanaland.
Split into many continents.

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

Palaeomagnetism?

A

Continental drift evidence.
Magnetic material in solidified rocks points north.
The earth magnetic field rotates, making the rocks point in opposite directions.
This is symmetrical on both sides which shows the plates are moving apart.

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

Hot spots

A

Intraplate
Surface manifestations of magma that rises to the surface.
Punches through the lithosphere.
Chain of volcano’s.
Lithosphere moves volcano of hotspot - extinct.
Example Hawaii
Eroded down into seamounts and guyots.

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

Horst and grabben

A

Tectonic plates diverge apart due to rising magma and convection currents.
Grabben subsides due to gravity.
Magma may rise up faults, leading to volcanic activity.
Shallow earthquakes.

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

Converging plate boundary

A

Subduction: less dense plate carried under another.

Convection currents carry plates towards one another.

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

Oceanic - continental

A

Subduction of oceanic plate as less dense.
Partial melting of oceanic plate.
Less dense magma rises, through weakness in the rock.
Forms volcano on surface.
Volcano explosive because high silica magma (andesitic)

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

Features of convergent plate boundaries?

A

Benioff zone: earthquakes (friction)
Deep ocean trench
Batholiths: magma cooled below surface.
Volcano

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

Primary waves

A

Travel the fastest.
Are compressional waves.
Can travel through solids and liquids.

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

Secondary waves

A

Body waves.
Transverse waves.
Arrive behind P waves.
Cannot travel through liquids.

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

Surface waves?

A

Love and reyleigh.
Long waves, more damaging, as closer to the surface.
(L) vibrate ground sideways.
(R) causes a ground rolling motion.

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

Focus and epicentre

A

Focus: point within the earth where the pressure was released/ earthquake occurred.
Epicentre: the point on the earths surface, directly above the focus.

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

Difference between richter and mercalli scale?

A

Richter: measures the magnitude of an earthquake.
Mercalli: measures the intensity of an earthquake.

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

Earthquake consequence: TSUNAMI

A

Earthquakes cause a large displacement of water. Which causes waves traveling high and fast.
Causes loss of lives, destroyed infrastructure, and spread of disease.

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

Earthquake consequences: LANDSLIDES

A

Vibrations from earthquakes cause sediment on hills to collapse.
Can lead to deaths, loss of possessions, and homes destroyed.

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

Earthquake consequences: LIQUEFRACTION

A

Vibrations cause sediments to act as liquids, and objects above will sink.

16
Q

Earthquake consequences: BUILDINGS DESTROYED.

A

Poorly built buildings can pancake which leads to death

Causes homelessness and loss of possessions.

17
Q

Earthquake consequences: pipelines destroyed

A

Could contain water, electricity and gas.

Could lead to a spread of disease, explosions and spread of fires.

18
Q

Earthquake consequences: INFRASTRUCTURE DESTROYED

A

Roadways destroyed prevents supplies getting into an effected area.
No medical supplies, services, food, and water can get into the area.