Paper 1 - Hazards

Question 1

Definition - Aseismic buildings

Answer 1

Buildings designed to withstand or minimise destruction during an earthquake

Question 2

Definition - Asthenosphere

Answer 2

The upper mantle layer of the Earth. It is semi molten and approximately 2000km wide

Question 3

Definition - Ash

Answer 3

Fine particles and dust ejected during an eruption, which can remain airborne as clouds accumulate on the ground

Question 4

Definition - Continental Crust

Answer 4

Crust that forms the continents of the lithosphere, on average 35km thick

Question 5

Definition - Continental drift

Answer 5

The movement of tectonic plates, due to varying weights of crust. It was originally thought that convection currents caused the movement of the plates, but now slab pull is thought of as the primary driving force

Question 6

Definition - Convection currents

Answer 6

The circulation of magma within the mantle. Magma is heated by radioactive processes in the core and cools at the surface, and so circulates between the 2 places

Question 7

Definition - Degg’s model

Answer 7

This model shows that a hazard becomes a disaster if it affects a vulnerable population

Question 8

Definition - Epicentre

Answer 8

The point on the surface, directly above the earthquake’s origin

Question 9

Definition - Fatalism

Answer 9

The belief that hazards are uncontrollable, so any losses should be accepted and mitigation is unnecessary

Question 10

Definition - Focus

Answer 10

The place in the crust where the pressure / seismic activity is released

Question 11

Definition - Hazard Management Cycle

Answer 11

The sequence of governance of a natural hazard - preparedness, response, recovery and mitigation

Question 12

Definition - Hot spot

Answer 12

Volcanoes found away from the plate boundary, due to a magma plume closer to the surface

Question 13

Definition - Jokulhlaup

Answer 13

A sudden glacial flood caused by a glacier on top of or near a volcano melting due to the heat from the eruption

Question 14

Definition - Lahar

Answer 14

A flow of mud and debris

Question 15

Definition - Lithosphere

Answer 15

The upper crust of the Earth - average thickness is 100km

Question 16

Definition - Love waves

Answer 16

A surface earthquake wave with horizontal displacement

Question 17

Definition - Mid ocean ridge

Answer 17

Parting oceanic plates at a constructive plate boundary creates a ridge, with new land at the base of the oceanic valley

Question 18

Definition - Moment Magnitude Scale

Answer 18

A measure of an earthquake’s energy released, considered the most accurate measure

Question 19

Definition - Oceanic crust

Answer 19

Crust, usually thinner than continental crust, that forms the sea floor. It is on average 7km thick

Question 20

Definition - Paleomagnitism

Answer 20

The alternating polarisation of new land created. As magma cools, the magnetic elements within will align with the earth’s magnetic field, which can alternate over thousands of years

Question 21

Definition - Park’s model

Answer 21

A model describing the decline and recovery of a country over time, following a natural disaster

Question 22

Definition - Partial melting

Answer 22

Elements within the lithosphere have different melting points, and so rock is partially melted, partially solid

Question 23

Definition - Primary waves

Answer 23

An earthquake wave causing compressions within the body of rock

Question 24

Definition - Pyroclastic flow

Answer 24

A mixture of gases and rock fragments, at high temperatures travelling at rapid speeds

Question 25

Definition - Richter scale

Answer 25

A logarithmic measure of an earthquake’s intensity

Question 26

Definition - Secondary waves

Answer 26

An earthquake wave causing vertical displacement within the body of rock

Question 27

Definition - Seismic waves

Answer 27

The energy released during an earthquake, in the form of primary, secondary, love and Rayleigh waves

Question 28

Definition - Rayleigh waves

Answer 28

An earthquake wave causing compressions within the body of rock

Question 29

Definition - Slab pull

Answer 29

The force contributing to the movement of tectonic plates. Slab pull is due to the weight of the plate

Question 30

Definition - Subduction

Answer 30

Oceanic plate is forced below continental plate, due to the oceanic plate being more dense than the continental plate

Question 31

Definition - Tsunami

Answer 31

Initial vertical water displacement creates waves, with large destructive power

Question 32

Definition - Volcanic Explosivity Index

Answer 32

A measure of the magnitude of a volcano’s eruptions

Question 33

Definition - Volcanic Island Arc

Answer 33

A series of volcanoes that are formed consecutively, as a tectonic plate moves across a magma plume

Question 34

Example of a key Tsunami case study

Answer 34

Japan 2011 Tsunami

• 15,000 deaths
• 1 million buildings damaged with 300,000 destroyed
• $250 billion in damages

Question 35

Example of a key volcanic case study

Answer 35

Eyjafjallajokul, Iceland - 2010

• 0 deaths
• Local population evacuated

Question 36

Example of a key earthquake case study

Answer 36

Port au Prince, Haiti - 2010

• 3,500,000 people affected
• 220,000 deaths
• 300,000+ injured
• 200,000 houses damaged - 100,000 destroyed
• 1,500,000 people became homeless
• $8 billion in damages

Question 37

Definition - Liquefaction

Answer 37

When soil is saturated, the vibration of a earthquake cause it to act like a liquid and more likely to subside when large weight is put upon it

Question 38

Definition - Preparedness

Answer 38

Being ready for an event to occur (public awareness education, training)

Question 39

Definition - Response

Answer 39

Immediate action taken after an event (evacuation, medical assistance, rescue)

Question 40

Definition - Recovery

Answer 40

Long term responses (restoring services, reconstruction)

Question 41

Definition - Mitigation

Answer 41

Strategies to lessen effects of another hazard (barriers, warning signals developed, observatories)