Earthquakes; Rock Cycle Flashcards
1
Q
scale of a earthquake
A
log factor 10
2
Q
how can we tell how much energy is generated in an earthquake?
A
- fractures
- how it moves
3
Q
What is the Mercalli scale?
A
- not about the magnitude of energy released
- not good
4
Q
What are P-waves
A
- compressional waves (like sound)
- faster
- primary
5
Q
What are S-waves
A
- transverse waves
- up and down
- do not go through fluids
- shear stress
- secondary
6
Q
what is a surface wave?
A
- motion does not depend upon distance from surface
- the same everywhere
- circular wave
- motion decreases as you go down (wave base)
- ocean
7
Q
What is wave base?
A
8
Q
A
the bigger they are the less they are
9
Q
where do earthquakes occur?
A
- plate boundaries
- mid-ocean ridge
10
Q
how do earthquakes feel at mid-ocean ridges?
A
shallow
11
Q
what is liquid faction?
A
- things turned to liquid when shaken
- sedimentary basements
- stiff at first
12
Q
what happens when an earthquake is in the ocean?
A
- water cannot support shear stress
- water displaced with surface waves (one plate goes up and the other down)
- wavelength decreases when wave base touches the floor
13
Q
when do waves break
A
1:7 ratio
14
Q
isostemic
A
bounds of weight
15
Q
A
- ocean crust getting older and denser
