Brainscape's Knowledge GenomeTM

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


See full index

Science > Earthquakes > Flashcards

Earthquakes Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

Layers of the earth…

A
  1. The atmosphere
  2. The crust
  3. The mantle
  4. The core
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How thick is the atmosphere and what is it made up of?

A

145km thick, contains mainly nitrogen and oxygen gases.

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

What are the five layers of the atmosphere?

A
  1. Exosphere
  2. Thermosphere
  3. Mesosphere
  4. Stratosphere
  5. Troposphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is the atmosphere held close to the earth?

A

by gravity

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

What is the ozone layer?

A

Is a band of ozone gases in the Earth’s atmosphere

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

the geological rock cycle describes how rocks:

A

are changed from one form to another.

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

what is the deepest known point on the Earth’s crust is approximately how many kilometres below sea level?

A

11km

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

the Earth’s mantle is thought to be 2900km thick. The temperature increases with depth. What effect would this geothermal gradient have on rocks within the mantle?

A

The rocks would be plastic and pliable (bendy, soft putty)

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

the temperature at the centre of the Earth is thought to be between…

A

5000-7000 degrees Celsius

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

how is the Earth’s magnetic field generated?

A

Liquid iron and nickel move within convection currents, along with the spinning of the Earth.

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

What are convection currents caused by?

A

Energy in the form of heat moving towards cooler regions.

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

The principle of superposition in geology refers to…

A

layers of rock, where the top layer will be younger than the lower layers.

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

What are fossils?

A

mineralised remains of plants, animals and micro-organisms.

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

What is the most frequent event that changes the planet?

A

Volcanism

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

what is the approximate age of the Earth?

A

4.6 billion years old.

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

What does the theory of plate tectonics say?

A

The Earth’s surface is covered by a series of crustal plates

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

subduction zones are where…

A

plates are converging, with one plate being pushed down into the mantle.

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

Liquefaction occurs when…

A

violent shaking of the ground causes ground water to move up to the surface.

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

What force of nature is acting to change the surface of the planet?

A

Gravity

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

Heavy atomic nuclei are split by slow-moving neutrons. This process is called:

A

nuclear fission

21
Q

Density can be described as:

A

the amount of matter in a unit of volume

22
Q

Tectonic plates are:

A

large parts of the Earth’s crust that float on the mantle.

23
Q

The Pacific Rim has a large number of volcanoes because:

A

Tectonic plates are being subducted along the boundary.

24
Q

The Earth’s magnetic field is thought to be generated by the:

A

Spinning of the outer core, which is predominately liquid nickel and iron.

25
Q

what are stromatolites formed by?

A

cyanobacteria colonies that trap sediment with their sticky surface coatings. The trapped sediment reacts with calcium carbonate in the water to form limestone.

26
Q

Besides earthquakes, what natural phenomenon changes the surface of the Earth more than any other event?

A

Volcanism

27
Q

Approximately how many years has the human species, Homo Sapiens, been present on the Earth?

A

6 million

28
Q

What observations would make you want to question whether or not the continents are moving?

A

The jigsaw shapes of the continents, similar fossils found on different continents and seismic activity.

29
Q

Explain what cyanobacteria are, when they first appeared on the planet and what the connection is between cyanobacteria and stromatolites. (short answer)

A

Cyanobacteria is blue-green algae or bacteria. Cyanobacteria cells have been discovered in the north-west of Australia, dating back to 3.4-3.7 billion years. Stromatolites are solid structures produced by cyanobacteria when sediment is trapped on the bacteria’s sticky surface- eventually solidifying. The trapped sediment reacts with calcium carbonate in the water to form limestone.

30
Q

What are ‘magnetic stripes’ in rocks, and how did their discovery help geologists explain plate tectonics?

A

While molten rocks cool and solidify, the magnetic elements of the rock align themselves with the local magnetic field and point north. Magnetic stripes in rocks indicate new seabed rock is being formed along the mid-ocean ridges. This helps to explain plate tectonics because different kind of rocks have been found in a variety of places.

31
Q

How would you explain evidence of past glacial activity in countries that now have hot climates?

A

A simple explanation of hot climate countries having evidence of past glacial activity is that the continent of Pangaea did exist. If the continents were arranged as one large continent located near the South Pole, then it provides a more logical picture of why glacial evidence exists where it does today. These glacial continents drifted to warmer climates. Changing climate means that glacier melted.

32
Q

List and briefly explain what evidence scientists have to support their view that the internal structure of the Earth consists of layers.

A

Scientists have based their ideas about the internal structure of the Earth on indirect and secondary measurements, usually seismic data and laboratory experiments on rocks and minerals. i.e. they use P and S waves and the time they take to travel around the planet. Also the composition of rocks-chemical and physical properties.

33
Q

Expand on the idea that where we build will help reduce damage and loss of life.

A

Build away from the coast or on higher ground to avoid tsunamis. build on solid ground to avoid liquefaction or subsidence. Build away or downwind from volcanoes to avoid ash.

34
Q

What is seismology? (3)

A
  • is the study of earthquakes and seismic waves.
  • Seismic waves are disturbances that travel through or around Earth.
  • The disturbance occurs when energy is released due to rocks breaking/exploding.
35
Q

About plate tectonics… (4)

A
  • subduction zone- a plate is pushed down by another
  • A huge amount of heat is generated
  • Turns rock into molten lava
  • sea floor spreading
36
Q

Plate boundaries…(4)

A

4 types of plate boundaries:

  • divergent boundaries- new crust forms and plates pull away from each other.
  • Convergent boundaries- crust is destroyed and plate dives under another.
  • Transform boundaries- plates slide horizontally past each other.
  • Plate boundary zones- plate interaction is unclear because boundaries are not well defined.
37
Q

How do earthquakes occur?

A

Earthquakes occur when tectonic plates move quickly past each other. The sudden movement of the tectonic plates produces shockwaves.

38
Q

What are the three types od shockwaves?

A
  1. P waves (primary waves)
  2. S waves (secondary waves)
  3. Surface waves
39
Q

About P-waves…

A

Move through solid and liquids by compressing the particles within matter together in the direction of the wave. P waves are the fastest waves and are the first waves recorded on a seismometer.

40
Q

About S-waves…

A

Move through solids only, they move particles of matter at right angles (i.e. up and down) to the direction of the wave.

41
Q

About surface waves…

A

They run across the surface of the Earth. they travel like sea waves but also vibrate and are very destructive. Also known as long waves, love waves and Rayleigh waves.

42
Q

Recording Earthquakes…(3)

A

seismologist- a person who studies earthquakes
seismograph or seismometer- detects and records seismic waves
seismogram- shockwaves recorded as a graph on paper.

43
Q

The Richter scale…

A

A Richter scale measures the size of earthquakes or magnitude using material recoded on a seismogram.

44
Q

What makes a building or structure fall in earthquakes?

A

Side-to-side waves. Heavier buildings have more chance of collapsing.

45
Q

The Mercalli scale… (3)

A
  • Indications from buildings
  • The Mercalli scale is a scale for measuring earthquake size based on how destructive the earthquake is.
  • The Mercalli Scale ranges from 1 to 10 in roman numerals.
46
Q

Effect on small buildings during earthquakes:

A

More affected, or shaken, by high frequency waves (short and frequent)

47
Q

Affect on tall building during earthquakes:

A

large structures or high rise buildings are more affected by long period, or slow shaking.

48
Q

Factors which matter during an earthquake (4):

A
  • strength of shaking
  • length of shaking
  • Type of soil
  • type of building

Science (9 decks)

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