The Challenge of Natural Hazards: Paper 1 Section A: Tectonic Hazards

Question 1

Two Types of Crust

Answer 1

Continental (Thicker+Less dense)
Oceanic (Thinner+More dense)

Question 2

Why do Plates Move

Answer 2

Convection Currents in the Mantle

Question 3

Destructive Margin

Answer 3

-Two plates moving towards each other
-Oceanic meeting continental the denser oceanic plate is subducted and destroyed creating gas-rich magma. Volcanoes and Ocean Trenches occur here.
-Continental meeting continental ground folds upwards creating fold mountains

Question 4

Constructive Margin

Answer 4

-Two plates moving away from each other
-Magma rises from the mantle to fill the gap and cools creating new crust

Question 5

Conservative Margin

Answer 5

-Two plates moving sideways past each other or in same direction
-At different speeds
-Crust isn’t created or destroyed
-Build of friction then snap past causing earthquakes

Question 6

Volcanoes Plate Margins

Answer 6

Destructive and Constructive

Question 7

Earthquakes Plate Margins

Answer 7

Destructive, Constructive and Conservative

Question 8

Moment Magnitude Scale

Answer 8

Measures the amount of energy released by an earthquake

Question 9

Chile Earthquake Stats of Chile

Answer 9

-27th Feb 2010
-3:34 am
-8.8 Richter Scale
-Destructive plate margin
-GDP per capita:
-Destructive Plate Margin
-Nazca Plate subducts under South American Plate

Question 10

Chile Earthquake Primary Effects

Answer 10

-Around 500 people died, and 12,000 people were injured. Over 800,000 people were affected
-Two hundred twenty thousand homes were destroyed, along with 4500 schools, 56 hospitals and 53 ports
-The cost of the earthquake is estimated to be US$30 billion
-The earthquake disrupted power, water supplies and communications across Chile

Question 11

Chile Earthquake Secondary Effects

Answer 11

-Tsunami waves devastated several coastal towns
-The tsunami struck several Pacific countries
-A fire at a Santiago chemical plant led to the local area being evacuated
-Landslides destroyed up to 1500 km of roads, cutting off remote communities for days

Question 12

Chile Earthquake Immediate Response

Answer 12

-Emergency services responded quickly
-International support provided field hospitals, satellite phones and floating bridges
-Within 24 hours, the north-south highway was temporarily repaired, allowing aid to be transported from Santiago to areas affected by the earthquake
-Within ten days, 90% of homes had had power and water restored
-US$60 million was raised after a national appeal, which funded 30,000 small emergency shelters

Question 13

Chile Earthquake Long-Term Responses

Answer 13

-Chile’s government launched a housing reconstruction plan just one month after the earthquake to help nearly affected 200,000 families
-Chile’s strong economy reduced the need for foreign aid to fund rebuilding
-The recovery took over four years
-Build Back Better

Question 14

Nepal Earthquake Stats of Nepal

Answer 14

-Kathmandu, Nepal
-25th April 2015
-11:26 am
-GDP per capita: US $690
-Destructive plate margin
-7.9 magnitude
-Indo-Asutralian Plate subducted under Eurasian Plate

Question 15

Nepal Earthquake Primary Effects

Answer 15

-Around 9000 died and more than 22000 were injured
-Estimated 800,000 buildings damaged or destroyed
-4 million left homeless
-Cost was US $5 billion
-Roads and bridges destroyed
-Water tanks and pipes destroyed, leaving 2 million without access to clean water and sanitation

Question 16

Nepal Earthquake Secondary Effects

Answer 16

-Earthquake triggered avalanches on Mount Everest killing 18 people
-Many mountain roads blocked by landslides preventing emergency aid reaching remote areas
-Lack of clean water caused outbreaks of typhus which killed atleats 13 people

Question 17

Nepal Earthquake Immediate Responses

Answer 17

-India and China sent teams to help residents rescue people trapped by debris but a lack of tool and machinery slowed down rescue efforts
-People tried to recover the dead and treat the injured but damaged roads made it hard for emergency workers and aid to get through
-Charities such as Oxfam provided medicine, food and temporary water supplies
-The Red Cross set up emergency shelters for 130,000 families who had lost homes

Question 18

Nepal Earthquake Long-Term Responses

Answer 18

-World Bank Group financed $500 mil worth of projects
-Road from Nepal to Tibet reopened 2 years after but many other routes remain damaged
-Many heritage sites were reopened in June 2015 to encourage tourists back
-Water supply being restored but 2 years after the event, many people had no access to clean water
-NGOs worked with residents to increase resilience to disasters