Brainscape's Knowledge GenomeTM

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


See full index

Physical Geography - Structures > Earth - Interior > Flashcards

Earth - Interior Flashcards

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

How does wave differ in materisl it is in?

A

Light waves travel fastest thoruhg vaccums, slower in air and slower in water, whilst sound waves do not travel in vaccums, travelling faster in water than it does in air.

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

Why are the properties of sound waves different to light?

A

Sound waves are variations in pressure, the more force taken to compress a material, the faster they travel.

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

What are the two types of wave?

A

Compressional
Shear

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

Comrpessional Waves

A

Waves where particle motion is same direction in which wave is propagating.

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

Shear Waves

A

These are waves changing the medium of which it travels, altering shape but not volume nor density.

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

Complication of measuring earth interior with waves…

A

Waves passing through more than one type of material exhibit seperate travel times and wave paths.

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

Seismic Wave Propogation

A

The passage of waves of compression/shear through rock and soil mediums.

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

How fast do seismic waves travel through Felsic, Mafic and Ultramafic rocks?

A

6, 7 and 8 km/s respectively.

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

Composotion of the contiental crust.

A

Low dense granite

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

Compositon of Ocean

A

Gabbro and Basalt

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

Mohorovivic Discontinuity

A

Boundary between the crust and the mantle

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

Composition of the Moho discontinuity…

A

Dense peridotite due to increased velocity of P waves.

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

Size of ocean, continent and orogenic mountain zone crusts…

A

7km, 33km and 70km.

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

Composition of upper mantle…

A

Ultramafic peridotite present, greater pressure and temperatures induce greater atomic compression.

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

Size of the lithosphere…

A

100km but varies geographically, maximising under continents and minimal near spreading centres where new crust forms.

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

Why does S-wave velocity decrease at base of lithosphere?

A

1% melting of peridotite minerals. (top of Astheno)

17
Q

Asthenosphere

A

The weak ductile layer the lithosphere plates slide.

18
Q

Why does s-wave velocity suddenly increase 400km below the crust?

A

Olvine mineral phase change

19
Q

Where is the second material phase change of olvine?

A

660km

20
Q

Transisiton Zone

A

410-660km where phase changes occur.

21
Q

Seismic Shadow Zone

A

This is an area of the Earth surface when direct P and/or S waves are detected.

22
Q

Rapid s-wave change at core-mantle boundary…

A

2890km where change from solid silicate rock to liquid iron alloy.

23
Q

Why does the core and mantle not mix?

A

Vast density differnece(greater than atmosphere-lithosphere difference)

24
Q

What is the core made of?

A

Iron and nickel and lighter elements

25
Q

What causes internal heat generation?

A

50% of heat is generated by radioactive decay.

26
Q

What drives heat flow and Earth cooling?

A

Conduction and Convection, both lithospheric and interior processes respectively.

27
Q

What is conduction a function of?

A

Atomic vibration and mechanical transfer of heat to surroundings, from hot regions to cool

28
Q

Passive Margins

A

Sites where continents have rifted apart becoming seperated by an ocean.

29
Q

What does conductive cooling cause?

A

Subduction of passive continental margins and thermal subsidence basins

30
Q

Convection of mantle/core…

A

Cyclic nature of heating/rising of a fluid, where its original position is displaced by colder temperatures.

31
Q

Why is convection quicker than conduction?

A

Heat is transported WITH the material.

32
Q

Dynamo Theory

A

This is the mechanism by which a celestial body generates in magnetic field.

33
Q

Nondipole Field

A

The part of the magnetic field contributed by internal geomagnetic processes.

Physical Geography - Structures (10 decks)

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