Earthquakes

Question 1

how are earthquakes measured

Answer 1

using MMS

Question 2

how are earthquakes caused at a destructive plate boundary

Answer 2

front of plate is moving slower as it hits the other one
this means that the back of the plate pushes into the front part causing a pressure build up.
the plate then slips and jolts forward releasing seisemic energy

Question 3

how are earthquakes caused at a colliosion plate boundary

Answer 3

front of plate is moving slower as it hits the other one
this means that the back of the plate pushes into the front part causing a pressure build up.
the plate then slips and jolts forward releasing seisemic energy

Question 4

how are earthquakes caused at a conservative plate boundary

Answer 4

the plates snag when moving past each other.
part of the plate is then moving slower as it hits the other one
this means that the back of the plate pushes into the front part causing a pressure build up.
the plates then slip and jolt forward releasing seisemic energy

Question 5

how are earthquakes caused at a divergant plate boundary

Answer 5

lithosphere is rifting which releases very small amounts of seizemic energy.

Question 6

whats the focus

Answer 6

where the energy is released from in the earth -physical

Question 7

whats the epicentre

Answer 7

the place directly above the focus on earth -human

Question 8

three things that effect the magnitude of an earthquake

Answer 8

-depth
-pressure
-geology (rocks)

Question 9

how does depth effect an earthquakes magnitude

Answer 9

shallow = strong but focused
deep = weaker but larger area effected.

Question 10

how does pressure effect an earthquakes magnitude

Answer 10

how long its been building up
how much energy is released
how much energy the plated can create

Question 11

how does geology effect an earthquakes magnitude

Answer 11

type of rock
- harder = less dangerous
- softer = more dangerous

presance of water

Question 12

what are the four waves released in their subgroups

Answer 12

Body waves: (deep in the body of earth)
- primary waves
- secondary waves
Surface waves: (Near the surface)
- Love waves
- rayleigh waves

Question 13

describe the body waves

Answer 13

primary:
very fast 6km/s, non destructive, very deep, go through liquid
secondary:
very fast 4km/s, small rolling motion so small damage, deep, travel through liquid

Question 14

describe surface waves

Answer 14

love:
slow 1km/s, devastating, on the surface, perpendicular motion, dissipated in liquid
rayleigh:
slow 1km/s, devastating, reverse rolling like ocean waves, on the surface.