Restless earth

Question 1

Conservative plate margin

Answer 1

2 plate margins sliding against each other at a different speed and angle. This causes earthquakes
E.g San Andreas fault

Question 2

Constructive plate margin

Answer 2

2 plates moving away from each other. This causes cracks and holes where there is a high chance of the magma to come out

Question 3

Destructive plate margins

Answer 3

Collision: 2 continental plates moving against each other on a head on buckle
Subduction: 2 (oceanic and continental) plates moving against each other with one of them (oceanic) being subduct under the continental plate (volcano)

Question 4

Structure of the earth

Answer 4

Core - Heats up mantle
Mantle - convection currents
Crust - tectonic plates

Question 5

Oceanic crust

Answer 5

Newer (less than 200 million years old)
Denser
Can sink
Can be renewed or destroyed

Question 6

Continental crust

Answer 6

Older (over 1500 million years old)
Less dense
Cannot sink
Cannot be renewed or destroyed

Question 7

Fold mountains and formation

Answer 7

Large mountain ranges formed with rock layers crumpled together

• forms when plates move against each other. If occurs in the same area with ocean trenches, it is subduction
• if formed by itself, collision has taken place

Question 8

Ocean trenches and formation

Answer 8

Deep sections of the ocean

• formed when plates move against each other
• if occur in the same area with fold mountains, it is due to subduction
• if by itself, it is collision

Question 9

Composite volcanoes and characteristics

Answer 9

Volcano made up of lava and ash
Infrequent, violent eruptions
Steep slopes and narrow base
Layers if thick lava and ash

Question 10

Shield volcano and characteristics

Answer 10

Volcano made of mostly lava
Frequent, non violent eruptions
Wide base and gentle slopes
Layers of runny lava and little ash

Question 11

Supervolcano and and characteristics

Answer 11

• a big volcano that erupts 1000 km squared of material
  Bigger than normal volcanoes
  Found in large depressions called calderas
  Emits 1000 km squared of material

Question 12

Formation of a supervolcano

Answer 12

Rising magma cannot escape through crust, this causes a large bulge to appear on the surface
Cracks appear in the surface making gas and ash escaping through
Magma chamber collapses, forming a caldera

Question 13

Difference between focus and epicenter

Answer 13

Epicenter is on the surface

Focus is below the surface

Question 14

Strength of Earthquakes at Different plate margins

Answer 14

Destructive: pressure from sinking plates can cause strong earthquakes
Constructive: friction and pressure from moving apart plates causes less severe earthquakes
Conservative: pressure released from stucked plates will cause a great and severe earthquakes

Question 15

How to measure earthquakes

Answer 15

Using seismographs to record extent of the earthquake
The Richter scale
The mercalli scale

Question 16

The three P’s

Answer 16

Prediction - forecast an event of where and when
Protection - construct modern buildings so they are immune to the effects of an earthquake
Preparation - organizing drills so civilians are aware of safe areas and points

Question 17

Tsunami and formation

Answer 17

A large wave of water moving towards shores triggered by an earthquake
Formed when crust is shifting and driven by the wave