earthquakes

Question 1

where do earthquakes occur

Answer 1

at all 4 types of plate boundaries

Question 2

what are earthquakes caused by

Answer 2

tension that builds up at a plate boundary

Question 3

how do earthquakes form at a destructive plate boundary

Answer 3

tension builds up when a plate gets stuck

as its moving down past the other into the mantle

Question 4

how do earthquakes form at a constructive plate boundary

Answer 4

tension builds up along the cracks within the plates

as they move away from each other

Question 5

how do earthquakes form at a collision plate boundary

Answer 5

tension builds up as the plates are pushed together

Question 6

how do earthquakes form at a conservative plate boundary

Answer 6

tension builds up when the plates grinding past each other gets stuck

Question 7

where are the shock waves spread out from

Answer 7

the focus

Question 8

what is the focus

Answer 8

the point in the earth’s crust where the earthquake starts

Question 9

where are the shock waves stronger

Answer 9

near the focus and causes more damage

Question 10

what is the epicentre

Answer 10

the point on the earth’s surface directly above the focus

Question 11

what 2 ways are earthquakes measured

Answer 11

using the moment magnitude/Richter scale or the Mercalli scale

Question 12

what does the moment magnitude/Richter scale measure

Answer 12

the energy released by an earthquake

Question 13

what does the Mercalli scale measure

Answer 13

effect

Question 14

what is a shallow focus caused by and what is the focus of it

Answer 14

caused by tectonic plates moving at/near the surface. They have a focus between 0 - 70km below earth’s surface

Question 15

what is a deep focus caused by and what is the focus of it

Answer 15

caused by crust that’s been subducted into the mantle moving towards the centre of the earth, heating or decomposing

Question 16

what is the focus of a deep focus

Answer 16

70-700km below earth’s surface