hazards

Question 1

Assess the extent to which people’s perception of hazards is likely to affect their responses to them

Answer 1

1. outline perceptions of hazards
2. outline responses as a result of perceptions
3. assess the extent so other characteristics that affect response e.g. wealth/age/education/religion

Question 2

Discuss the structure of the earth

Answer 2

1. earth constructed of core/mantle/crus
2. core has solid inner/out liquid made of iron n nickel
3. mantle semi molten upper and rigid lower
4. crust oceanic and continental

Question 3

what is meant by gravitational sliding

Answer 3

1. occurs at constructive boundaries/also known as ridge push
2. magma rises to the surface to create new crust
3. heats surrounding rocks causing them to expand and rise forming a slope
4. new crust cools and becomes denser so it moves downslope
5. this puts pressure on the plates causing them to move apart

Question 4

Assess the importance of the plate tectonic theory in helping to understand the nature and causes of seismic and volcanic activity

Answer 4

1 define ptt and Alfred Wegner
2. sea floor spreading/paleomagnitism (involved study of underwater rocks) validated existence of plates
3 ideas showed role of convenction/slab pull and ridge push in causing plate movement
4. types of margins

Question 5

Outline the plate tectonic theory

Answer 5

define ptt and Alfred Wegner
2. sea floor spreading/paleomagnitism (involved study of underwater rocks) validated existence of plates
3 ideas showed role of convenction/slab pull and ridge push in causing plate movement
4. types of margins

Question 6

Outline the causes of a storm surge 3 points

Answer 6

1. storm surge is an increase in sea levels
2. caused by extreme low pressure and high wind speeds
3. occurs as a tropical storm makes landfall

Question 7

Analyse the extent to which the impacts of volcanic hazards depend upon the nature of the vulcanicity

Answer 7

1. vulcanicity differs at different plate margins
2. constructive - shield volcanoes
   -basaltic lava, runny, hot , flows quickly
   hazards inc lava flows, volcanic gases, fissures
   these cause less damage as they are slow and people can evacuate
3. destructive boundary: andesitic and rhyolitic lava which is cooler but more vicious
   compositie volcanoe
   pyrocrastic flows/volcanic gases
   fast/destrcutvie cause more damage

Question 8

Describe and explain the formation and impact of magma plumes

Answer 8

1. radioactive decay in earths core creates high temps and heats mantle
2. when the radioactive decay concentrates it creates local thermal currents
3. these causes plumes of magma to rise and burn through the earths lithosphere
4. this creates volcanic activity and forms volcanoes
5. these hotspots remain stationary as the plate moves creating island arcs like the Hawaiian islands

Question 9

he Disaster Response Curve (The Park Model) has contributed to improved understanding and therefore management of the impact of hazards

Answer 9

1. define park model ( indicates quality life against time after a disaster occurs)
2. visualually effective BUT can’t show qualitiative data
3. stage 5 effective at showing recovery and reconstruction BUT doesn’t take in to account temporal variations ( things done to mitigate before event)
4. versalitiy of model (any event) BUT lacks spatial variation as can’t be applied to more than one event and assumes all places recover at once

Question 10

what is meant by slab pull

Answer 10

1. occurs at destructive plate boundaries
2. denser crust is forced under less dense crust (subduction)
3. the sinking of the plate pulls the rest of the plate towards the boundary
4. the more crust subjected the quicker the plate movement

(like a necklace sliding off table)