Brainscape's Knowledge GenomeTM

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


See full index

EAS 210 > Chapter 9 - Premidterm > Flashcards

Chapter 9 - Premidterm Flashcards

1
Q

Degree of destruction of earthquake is dreependent on:

A

Magnitude of quake
bedrock
type of structure

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

How does bedrock correlate with earthquake? How can u use bedrock to your advantage

A

If you build structures on strong bedrock, magnitude of earthquake wave is smaller
-softer material, clay, water, large magnitude. CAREFUL

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

Other factors making earthquakes dangerous

A

Fires due to rupture of gas lines

land slides

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

What is hypocenter or focus of earthquake

A

exact point where it is caused

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

What is epicentre of earthquake

A

Point on surface right above hypocenter

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

Where do earthquakes occur

A

Most earthquakes occur in seismic belt corresponding to plate boundaries converge, diverge, transform

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

Can you build a house with 100% earthquake safety?

A

No. You can make the percentage very high, but earthquakes can occur anywhere

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

What is elastic rebound theory. What does it say

A

Explains causes of earthquakes

-stress builds up between 2 different piece of lands, then it ruptures and moves apart, stress is released in shockwaves

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

What are 4 types of shockwaves

A

P waves
Secondary wave
Rayleigh wave (r) wave
Loe wave (L) wave

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

Describe P wave

A

Compressional wave

  • travels same direction as deformation
  • MOST DESTRUCTIVE, fastest waves
  • longitudinal waves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe secondary waves

A

Shear waves

  • slower than primary wave, less destructive
  • moves at a right angle with direction of wave / with direction of P wave
  • moves up and down
  • shear objects, since liquids and gas aren’t solid, there is no shear stress, and there is no Secondary waves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Rayleigh wave, describe!

A

Slower, behaves like water waves

-moves forward, while particles move in an elliptical path within a vertical plane

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

Love wave, describe

A

Like S waves, but particles move back and forth in horizontal plane perpendicular to direction of wave

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

CAN S WAVES TRAVEL THROUGH SOLIDS GASES, WHY

A

NO CUZ OF SHEAR STRESS, NO SHEAR STRESS IN LIQUIDS GASES

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

CAN P WAVES TRAVEL THRU SOLIDS GASES?

A

YES

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

What are body waves

A

P and S waves

17
Q

What are surface waves

A

L and R (love and Rayleigh waves)

18
Q

Intensity vs magnitude of earthquake?

A

intensity is subjective, depends on how much damage done

magnitude is amount of energy released

19
Q

What scale is intensity of earthquake?

A

Modified mercalli intensity scale

-dependent on distance, population, types of buildings, like how much destruction done, intensity is subjective

20
Q

What scale is magnitude of earthquake?

A

Richter scale

  • measured by largest amplitude of seismic wave
  • on a log scale so difference between 5 and mag is 10
21
Q

How do we determine where epicentre of earthquake is?

A

Distance between arrival of P and S waves.

-we know velocities of both waves, so we can use that to determine

22
Q

How many seismic graphs do we need to determine where epicentre is?

A

3 seismic graphs

23
Q

For an area that just got an earthquake, whats the likelihood of another earthquake in same area?

A

Stresses accumulate in bedrock

  • when earthquake happens, that rock breaks, releases all the stress
  • if it recently had an earthquake, not likely it will happen
24
Q

How did we figure out the outer core to mantle boundary? How do we figure out outer mantle is liquid?

A

S waves cannot penetrate liquids

  • when they hit liquid outer core, they get blocked off
  • SHADOW ZONE
25
Q

Whats at the 30km mark into earth. How was this discovered?

A

MOHO

-weird P and S wave reaction suddenly 30km in earth surface

26
Q

Average density of rocks?

A

2.7-3 g / cm^3

27
Q

Japan earthquake and tsunami, height, dead#, homeless#

A

10-23m

  • 15k-25k dead
  • 500k homeless
28
Q

HOW DO WE PRECICT EARTHQAKES?

A

Seismic gaps
-segment of active fault known to produce significant earthquakes, that has not slipped in a long time compared with other segments along same structure

29
Q

WHAT ARE SEISMIC GAPS? WHAT DO THEY DO?

A

Seismic gaps
-segment of active fault known to produce significant earthquakes, that has not slipped in a long time compared with other segments along same structure
THEY HELP PREDICT EARTHQUAKES

EAS 210 (24 decks)

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