6.1 Earthquakes and volcanoes (impacts and stra)

Question 1

describe the structure of the Earth

Answer 1

crust,
mantle
(inner & outer) core

Question 1

crust

Answer 1

The outer layer of the Earth made up of solidified rocky plates.

Question 2

Mantle

Answer 2

The layer of molten rock on which the crust floats

Question 3

core

Answer 3

Outer core
made of very hot molten metal.

Inner core
made of solid metal

Question 4

Types of crust

Answer 4

1- The oceanic crust
2- Continental crust

Question 5

The oceanic crust (sial) features

Answer 5

➢ Very dense
➢ Younger
➢ Can sink and is constantly being destroyed and replaced

Question 6

2- Continental crust

Answer 6

➢ Light weight
➢ Old
➢ Cannot sink and cannot be destroyed

Question 7

Plate boundaries

Answer 7

where two or more plates meet.

Question 8

3 types of plate boundaries

Answer 8

constructive,
destructive
conservative

Question 9

Constructive/Divergent plate boundary

Answer 9

• when there are two plates moving apart from each other.
• They are called constructive plates because when they move apart a gap is created, magma rises up in the gap and forms lava and solidifies- this forms volcanoes.

Question 10

Destructive/convergent plate boundary

Answer 10

• This occurs when oceanic and continental plates move towards each other.
• The oceanic plate is forced under the lighter continental plate as it is denser.
• Forming a sebduction zone.
• Friction causes melting of the oceanic plate converting it to magma and may trigger earthquakes.
• Magma rises up through cracks and erupts due to pressure onto the surface and forms a destructive volcano

Question 11

Conservative/ transform plate boundary:

Answer 11

• Plates slide past each other in opposite directions, and gets stuck
• Friction takes place between the plates and pressure builds up,pressure is releases as plate move suddenly;
• This creats a seismic wave through the crust from the focus leading to earthquake

Question 12

What are Volcanoes

Answer 12

An opening in the earths crust through which magma from eithin the mantle is erupted onto the land

Question 13

Causes of valcanoes

Answer 13

Constructive plate boundary
Destructive plagte boundary

Question 14

Shield volcanoes

Answer 14

➢ Found on constructive plate boundaries
➢ low height and wider base
➢ gentle slope

Question 15

Composite volcanoes

Answer 15

• Found on a destructive plate boundary
• high height shorter base
• steep slope

Question 16

Distribution of volcano and earthquake

Answer 16

Both:
* Encircle the whole of the pacific ocean (ring of fire)
* Extend down the entire length of the mid-atlantic ocean
Earthquake-
* stretch across the southern Europe and Asia
Valcanoes-
* some in southern Europe, the Caribbean and east africa

Question 17

Earthquakes

Answer 17

The shaking and vibration of the Earth’s crust due to movement of the earth’s plates (plate tectonics)

Question 18

Causes of Earthquakes

Answer 18

Conservative plate boundary
sometimes destructive

Question 19

How are earthquakes measured?

Answer 19

The Richter Scale measures the magnitude of a tremor (how powerful it is) using an **instrument called a seismometer **

Question 20

Impacts of tectonic events (volcanoes and earthquakes)

Answer 20

1. damage to buildings and infrastructure,
2. fire,
3. tsunamis,
4. landslides,
5. loss of farmland and habitats, leading to starvation
6. water-related disease,
7. loss of life,
8. trauma,
9. financial losses

Question 21

Managing the impacts of tectonic events (earthquakes and volcanoes)

Answer 21

• monitoring and warning,
• land use zoning (not building on areas prone to hazard)
• structure of buildings (earthquake proof)
• disaster preparation (plans, drills, emergency supplies and emergency rescue teams),
• evacuation plans
• rebuilding of damaged areas,
• international aid
• food storage
• hazard zone map

Question 22

Opportunities presented by valconoes

Answer 22

• Tourist attraction
• provide income and employment
• fertile soils,
• Exraction of minerals,
• heat generated provide good source for geothermal energy resources

Question 23

why do more people die AFTER
earthquakes

Answer 23

● lack of medical help
● lack of clean water
● outbreak of water related diseases
● lack of food
● crime
● lack of shelter
● risk of aftershocks

Question 24

why do people continue to live in region with natural hazards

Answer 24

● nowhere else to move
● familial ties
● lack of money
● no employment
● Confidence in prediction, preparation and protection.