Earthquakes Flashcards
At what kind of plate boundary did the Sichuan earthquake occur?
Collision; where the Indian and Eurasian plates meet
When did the Sichuan earthquake occur?
12th May 2008
What was the effect of the Sichuan earthquake on the la d around it?
Moved 9m north
What magnitude was the Sichuan earthquake?
7.9
During the Sichuan earthquake, shockwaves could be felt in Beijing and Shanghai. How far away are these cities from the epicentre?
1500km and 1700km
Why was it difficult to get relief to Sichuan?
Routes blocked by landslides caused by the earthquake
In terms of GDP, Sichuan ranks ….. out of 31 Chinese provinces.
25th
Why did so many buildings in Sichuan collapse?
They were poorly built, despite building regulations; schools were particularly bad
How ,may classrooms collapsed in Sichuan?
7000, killing 19,000 children
How many people died in the Sichuan earthquake?
Around 90,000
How many people were evacuated from Sichuan?
15 million
How many people in Sichuan were displaced?
5 million
How many buildings in Sichuan were destroyed?
5 million, 21 million were damaged
What were the secondary impacts of the Sichuan earthquake?
700 people killed in landslide in Qingchuan, fracturing of nearly 2,500 dams, threat of flooding for 700,000 people
How might humans have caused the Sichuan earthquake?
The Zipingpu Dam, holding 315 million tonnes of water, was completed two years before the earthquake and is located 5km away from the epicentre
How many lakes were created by landslides in Sichuan?
34
How had China tried to modify the vulnerability of people in earthquake prone areas?
Provinces were identified as at different levels of risk, then each level had building regulations; any construction after 1976 in Sichuan should have been reinforced with steel
How many buildings in Japan were destroyed by the Sendai earthquake and tsunami?
112,000
How many people died or are missing after the Sendai earthquake and tsunami?
20,000
Why were people in towns such as Minami Sanriku vulnerable to the tsunami?
Their houses don’t have foundations, so they were swept away
Which buildings of importance were destroyed in the tsunami at Minami Sanriku?
The bottom four floors of the hospital were wiped out, the tsunami warning tower was destroyed causing the death of a woman who stayed to warn everyone over intercom
What sea defences did the Fukushima power plant have in place?
5.5m sea wall, tsunami waves were twice this height
What effect did the tsunami have on the Fukushima power plant?
Short circuited cooling system causing reactor to explode
Why is Japan so susceptible to earthquakes?
It lies in the Pacific Ring of Fire, where four plates (NA, Pacific, Philippine and Eurasian) are all moving towards each other
What magnitude was the Sendai earthquake?
9
What effect did the Sendai earthquake have on the land around it?
It moved 10m along a 400km fault
How did the tsunami travel?
In deep water waves were around 50cm tall with wavelengths of 100km rather than the normal 10s of m, little energy lost, 700km/h; in shallow water slowed, got taller (over 10m)
How long did it take the tsunami to hit after the earthquake?
30 minutes
How many people were made homeless by the Sendai earthquake and tsunami?
500,000
How many people had to live in temporary shelters in Japan?
150,000
What were the immediate responses to the Sendai earthquake and tsunami?
Search and rescue, exclusion zone set up around Fukushima power plant, homes evacuated
How were people in Japan warned of the earthquake and tsunami?
Automatic warnings sent to phones and TVs
Where was the hypo centre of the Sendai earthquake?
100km off the east coast of Japan
What proportion of the deaths in Japan were due to the tsunami?
90%
How long did it take to get rid of all the debris in Japan?
3 years
How much was the insurance bill after the Sendai earthquake and tsunami?
£20 billion
Japan experienced its first trade deficit in …… years.
30
In what way was Japan more prepared for an earthquake than Sichuan?
Building regulations had been adhered to and had proved effective
When did the Sendai earthquake occur?
11th March 2011
When did the Shinkansen begin operations again?
End of April
What effect has the Fukushima nuclear disaster had on people living near it?
20km radius evacuated, couldn’t return to homes as radiation levels are 15 times higher than before, water and food may be contaminated, fish can’t be eaten for 10 years
What is a soft storey?
The bottom storey of a building that is designed to collapse to minimise damage to the above storeys (car parks)
How are buildings in Japan protected from fire?
Fire-resistant, advanced firefighting facilities, smart meters that automatically shut off gas supplies in an earthquake
What do citizens of Tokyo all have?
Emergency earthquake supplies, knowledge of evacuation routes and shelters
What can be put into houses to minimise the damage of earthquakes?
L-shaped brackets secure bookshelves, cabinets etc to walls, strategic placement of beds (not near windows) and heavy items (not on shelves)
What is cross-bracing?
A form of earthquake proof architecture involving diagonal supports; during an earthquake one may be in tension and the other in slack, allowing movement
Why are moats used in skyscraper building?
Skyscrapers may be built to swing in an earthquake, so moats/buffer zones surround them to ensure buildings don’t collide
When was the Nepal earthquake?
25th April 2015
What was the magnitude of the Nepal earthquake?
7.8
What was the distance between Kathmandu and the earthquake epicentre?
81km
When was the major aftershock of the Nepal earthquake?
12th May; magnitude 7.3
How many people died in the Nepal earthquake?
Around 9,000 and 50,000 people were internally displaced
How much may the Nepal earthquake have cost?
$7 billion, a third of GDP
Why was access to remote villages in Nepal difficult?
Roads were blocked by landslides, collapsed buildings, tension cracks; helicopters couldn’t be flown into some areas due to fears of blowing roofs off houses
