Tectonic hazards

Question 1

When was the Japan earthquake and how strong was the magnitude

Answer 1

March 2011
9.0 magnitude on the Richter scale

Question 2

What were the primary effects of the Japan earthquake

Answer 2

• violent ground shaking for up to 5 minutes, causing many injuries and deaths as buildings collapsed
• shaking destroyed homes
• roads and railways were damaged
• electricity and water systems disrupted in tohoku
• over 4 million people in North-East Japan were left without electricity
• 1.5 million left without water
• In Fukushima, a dam burst

Question 3

What were the secondary effects of the Japan earthquake

Answer 3

• 10 metre high waves caused almost all of the 18,000 deaths and left 500,000 homeless
• About 560km squared of coastal land was inundated
• waves destroyed port facilities, infrastructure and homes
• many had to live in temporary structures for months
• Explosions at Fukushima powerplant lead to evacuation of 100,000 people

Question 4

Immediate responses to the Japan Earthquake

Answer 4

• 100,000 members of the Japanese self-defense force were sent to rescue
• 500,000 people were evacuated to higher ground before the tsunami
• roads and railways networks restored, improving access to region.
• power was soon restored but supply was intermitted due to explosion at the Fukushima nuclear power station

Question 5

Long term responses to Japan earthquake

Answer 5

• Reconstruction Design Council devised a long-term plan for the region
• By early 2015, most debris had been cleared and new housing constructed
• by 2020 almost all the temporary homes were replaced by public housing
• in 2013 an upgraded tsunami warming system was launched, providing faster and more accurate forecasts
• sea walls up to 12.5m high and embankments constructed

Question 6

When was the Nepal earthquake and how strong was the magnitude

Answer 6

April 2015
7.8 magnitude on the Richter scale

Question 7

Immediate responses to the Nepal earthquake

Answer 7

• international search and rescue teams saved 16 survivors
• water and medical support arrived from the UK, China and India
• 1.4 million people needed water food and shelter, World Vision International provided food kits for 8000 people and shelter materials for 20,000 people
• helicopters rescued people caught in avalanches on Mount Everest
• field hospitals were set up , Red Cross

Question 8

Long term responses to Nepal Earthquake

Answer 8

• Nepal adopted a new National Disaster Risk Reduction policy
• end of 2015 most access to roads had been repaired
• Trekking routes on Mount Everest restored and tourists returned
• UNESCO is working with the government to restore 700 damaged temples

Question 9

Why do some people live in hazardous areas

Answer 9

• Plate margins often coincide with very favourable areas for settlement, such as coastal areas where ports have developed
• volcanoes can bring benefits such as fertile soils, rocks for building, rich mineral deposits and hot water
• better building design can withstand earthquakes so people may feel less at risk
• more effective monitoring of volcanoes and tsunami waves enable many people to receive warnings and evacuate before events happen
• large earthquakes and volcanic eruptions don’t happen very often, most don’t see them as a great threat

Question 10

How are volcanoes formed at constructive plate boundries

Answer 10

• two tectonic plates are moving away from each other
• the rising magma pushes its way to the surface
• It escapes as lava forming a volcano
• the magma is very hot meaning it flows a while before cooling, this means they are normally broader with gently sloping sides
• Known as shield volcanoes (such as Eyajafjalla in Iceland)