Tectonics

Question 1

Describing the pattern volcanoes and earthquakes

Answer 1

1-Plate boundaries
2-Linear
3-Anomalies (hot spots) - found in the middle of a plate
4-(Often along the coast)

Question 2

Divergent Plate Boundary

Answer 2

1-Atlantic Ocean (Mid Atlantic Ridgeline)
2-North America and Eurasia moving away
3-Moving away
4-Creates a gap
5-Magma rises to fill the gap
6-Magma solidifies
7-Create volcanoes and new land (e.g. Iceland)

Question 3

Convergent Plate Boundary

Oceanic and Continental

Answer 3

1-Nazca plate (O) towards the South American plate (C)
2-Move towards each other
3-Oceanic is more dense - sub ducted
4-Continental is less dense
5-Creates friction and heat
6-Creates violent earthquakes - high magnitude
7-Heat melts the rock
8-Creates Magma
9-Magma rises
10-Violent euription on surface - volcano
11-Can create fold mountains

Question 4

Conservative Plate Boundaries (Passive)

Answer 4

1-San Andreas Fault line
2-North American plate - Pacific plate - move past
3-Jerking movement - rocks get stuck + locked in position
4-Build up of tension
5-Sudden release
6-Release of energy from focus = earthquake
7-Releases seismic waves

Question 5

Hot spots

Answer 5

1- Happens mid-plate - magma moves to the surface causing a magma plume
2- Magma is less dense then surrounding mantle
3- Causes the surface/crust to dome - when magma finds a weakness it erupts on the surface
4- Has to repeat before a volcano forms on the surface
5- Hawaii

Question 6

3 Reasons why people live near volcanoes

Answer 6

1- Ash turns in to fertile soil - soil = high level of nutrients - can be used to grow crops - Vesuvius (grow oranges)
2- Doesn’t happen often - if they have a good job they stay - Hawaii/Japan
3- Minerals - diamonds/tin - Chile

Question 7

3 Reasons why people live where there are earthquakes

Answer 7

1- California - houses are highly valued and the area is nice to live in
2- Houses are built with good foundations - people think its safe to stay - San Francisco + LA
3- LIC’s - people don’t have money to move - friends/family live there

Question 8

How to measure the magnitude of Earthquakes

Answer 8

1- Mercalli Scale - measures the damage/impact on people - less scientific
2- Richter Scale - measures the magnitude

Question 9

Focus

Answer 9

Where the rock gives way

Question 10

Epicentre

Answer 10

Point on the earths surface directly above the focus

Where the seismic waves are the strongest

Question 11

Predicting earthquakes

Answer 11

1-
2-
3-

Question 12

Predicting volcanoes

Answer 12

1-
2-
3-

Question 13

Building design earthquakes

Answer 13

1-

2-

Question 14

Prevention earthquakes

Answer 14

1-

2- Disaster prevention day - Japan - 1st September

Question 15

Preventing volcanoes

Answer 15

1- Detonating explosives - Hawaii
2- Earth walls + holes - Mt. Etna
3- Spraying sea water - Iceland