Tecotnic

Question 1

What’s a constructive (divergent) plate margin

Answer 1

Plates move away

Question 2

What’s a destructive (convergent) plate margin

Answer 2

Plates move together and collide if both continental. Oceanic subduction if continental and oceanic vied on subduction if both oceanic

Question 3

Where are volcanoes found

Answer 3

Active volcanoes are found at constructive/destructive and at hotspots

Question 4

Volcanoes: What happens a constructive plate margin

Answer 4

Magma is less dense than plate so rises above it (similar to ridges)

Question 5

Volcanoes: what happens at a destructive plate margin

Answer 5

Subduction causes me,ting of oceanic plate, allowing magma to rise and form a volcano

Question 6

What does the shape of the volcano give?

Answer 6

It will determine its destructive ability (e.g composite cone are usually more destructive than shield)

Question 7

What do primary and secondary hazards include in a volcano?

Answer 7

Primary: include lava flows, phreatic (steam) eruptions and pyroclastic flow carry hot ash and rock

Secondary:
Involve water in form of Lahars and jokuhlaups

Question 8

What’s an earthquake

Answer 8

They are most powerful at conservative and destructive

Question 9

Earthquake: what happens at a constructive plate margin

Answer 9

Plates move at different speeds building, building up pressure until plates crack, causing fault lines and releasing seismic waves

Question 10

Earthquake: what happens at a conservative plate margin

Answer 10

Locked fault between plates building up pressure and suddenly releasing seismic waves

Question 11

What is a natural hazard caused by?

Answer 11

Either climatic (meteorological) or land (geophysical) processes

Question 12

What is a hazard

Answer 12

Potential threat to human life and property

Question 13

Where does a geophysical hazard happen

Answer 13

Near plate boundaries

Question 14

Where do earthquakes happen

Answer 14

Happen in the middle of plates (intra-plate) caused by pre existing weakness that reachuate and produce seismic waves

Question 15

Where are volcanic hotspots (e.g ring of fire) found?

Answer 15

Found in the middle of plates
Found on earths crust and upper mantle where’s there’s high temperature from upswelling and hot molten material from the core

Question 16

What is the role of development and governance on impacts

Answer 16

People remain vulnerable to disasters risks due to inequality such as education, health care and income

Urbanisation and population growth means that more people are vulnerable increasing the amount of poverty

In Japan they prepare for hazards

Having public infrastructure, housing, food supplies and health care can lower the impacts In a disaster

Poor governance means that the hazard is more likely to turn into a disaster

Governance is seen as the root cause and critical n the case of a hazard/disaster

Question 17

What is the Richter scale and what does it measure?

Answer 17

It measures magnitude and uses the arrival times of P and S waves

Question 18

What is the moment magnitude scale and what does it measure?

Answer 18

It uses the energy released and the movement produced by shock waves to calculate magnitude

Question 19

What can earthquake intensity be measured by?

Answer 19

The Mercalli scale- this takes into account the damage

Question 20

What are volcanic eruptions measured by

Answer 20

Volcanic explosivity index- uses the amount of energy released and the type of eruption to calculate a value

Question 21

Definition of disaster

Answer 21

When a hazard affects human weathering

Question 22

Definition of vulnerability

Answer 22

How susceptible a population is to damage caused by a hazard

-capacity to cope of how resilient the population is can affect how well it can recover

Question 23

Definition of risk

Answer 23

He livelihood of humans being affected by a hazard

This is calculated by the hazard risk equation

(Hazard x vulnerability divided by capacity to cope)

Question 24

Risks of disasters

Answer 24

It increases as the severity/frequency of the hazard increases as well as vulnerability.

However for a worse risk- capacity to cope will decrease along with everything else

Qatar- 0.1% has lowest risk
Phillipeans- 27.5% highest risk

Even if a country doesn’t have a major hazard- they can still be a risk because of their capacity to cope

Question 25

What is the pressure and release model

Answer 25

It’s made up of three key features: governance, dynamic pressures and unsafe conditions

Governance is seen as the main cause which affects the other two

Question 26

Example of governance (their limits to access and ideologies)

Answer 26

Limits to access:
Power
Resources
Infrastructure

Ideologies:
Political
Economy systems

Question 27

Examples of dynamic pressures (lack of and macro-forces)

Answer 27

Lack of:
Training
Local investment

Macro-forces:
Population change
Deforestation
Rapid urbanisation

Question 28

Examples of unsafe conditions

Answer 28

Environment

Local economy

Question 29

Examples of natural hazards

Answer 29

Earthquakes 
Flooding 
Landslides 
Volcanoes 
Winds
Drought