seismic & multi hazardous environment - TOHOKU

Question 1

how many EQ on average does japan have annually

Answer 1

1500
accounts for 1/3 of the worlds total

Question 2

order of events EQ and tsunami

Answer 2

1. moved the entire island of Honshu 2.4m closer to North America
2. shifted the Earth’s axis approx. 10cm
3. made earth days shorter by 1.8 microseconds
4. calved 125 km2 of iceberg from Antarctica’s coast
5. caused visible waves in Norwegian fjords

Question 3

time, date, location and size of EQ

Answer 3

2.46pm
Friday 11 March
mag. 9.0 EQ
occurred under the Pacific Ocean

Question 4

why did it happen

Answer 4

a segment of the North American plate that had been dragged down by the subducting Pacific Plate, slipped upwards between 5-10m.

Question 5

what did the EQ cause

Answer 5

this displaced water resulting in a tsunami at hundreds of km/h

Question 6

when and where did the first wave hit

Answer 6

1st wave hit the NE coast only 30 mins after the EQ

Question 7

how many waves were there

Answer 7

10

Question 8

how far apart were the waves

Answer 8

each 1km apart
as they reached shallower water, they slowed and piled up,
reaching 10m in height.

Question 9

what did the waves do to the tsunami defence walls

Answer 9

they overwhelmed tsunami defence walls and surged up to 10km inland.

Question 10

what impact did ground shaking have

Answer 10

buildings collapsed, some set ablaze by broken gas and petrol pipes

Question 11

when the tsunami swept inland what happened

Answer 11

caused devastation to boats, buildings, vehicles and trees
flooded an area of 500 square km

Question 12

what happened when the water receded

Answer 12

whole cities were in ruins
trains had vanished
ships and boats had been moved

Question 13

what happened in tokyo - skyscrapers

Answer 13

in Tokyo, skyscrapers started ‘shaking like trees’ = EQ proof design meant damage was limited

Question 14

sendai

Answer 14

areas near the sea were badly damaged, but the city centre was largely unaffected

Question 15

rikuzentakata

Answer 15

almost completely submerged and was almost totally destroyed

Question 16

minami-sanriku

Answer 16

half the population of 17,000 died
few buildings left standing

Question 17

how many dead/missing and why

Answer 17

18,000 + were dead/missing, mainly due to the tsunami, although the Japanese tsunami system saved many lives.

Question 18

how many made homeless

Answer 18

½ million people

Question 19

what social impact did it have

Answer 19

200,000 children now suffer from precancerous thyroid abnormalities, primary nodules and cysts.

Question 20

how many lived in shelters for weeks

Answer 20

150,000+

Question 21

how many homes left without running water

Answer 21

1 mill +

Question 22

how many homes left without electricity

Answer 22

6 million

Question 23

there were shortages of x, y, z

Answer 23

food, water, petrol and medical supplies

Question 24

what happened 2 weeks post EQ

Answer 24

there were more than 700 aftershocks, causing concerns and further damage.

Question 25

what happened to the fukushima daiichi power plant

Answer 25

explosions and radiation leaks at the Fukushima Daiichi nuclear power plant in the days after the EQ spread fear around the world.
EQ severed the power supply to the
cooling system.
tsunami then destroyed the backup generators.
workers struggled to prevent the meltdown.

Question 26

what conditions did survivors live in post disaster

Answer 26

in freezing temperatures, survivors huddled in shelters and hoarded supplies as rescue workers searched the coastline of submerged homes.

Question 27

how many soldiers helped and what did they help do

Answer 27

100,000 soldiers were mobilised to establish order, organised rescue work and distribute blankets,
bottled water, food and petrol.

Question 28

what did the uk send to aid the process

Answer 28

63 search and rescue specialists
two rescue dogs
a medical support team

Question 29

where was an exclusion zone set up

Answer 29

an exclusion zone was set up around the Fukushima Daiichi nuclear plant.
homes were evacuated and iodine tablets were distributed – to prevent radiation sickness.

Question 30

who coped well with the EQ

Answer 30

japan

Question 31

what was wrong with japans defence system

Answer 31

tsunami defences were inadequate against the height and force of the water.

Question 32

what will be done in the future to improve japans defence systems

Answer 32

future planning must consider whether
defences should be built to defend the coast against similar high magnitude, low frequency event.
special zones for reconstruction were designated with relaxed planning regulations to encourage
rapid rebuilding and tax incentives

Question 33

what did japan do in 2013

Answer 33

they unveiled a new upgraded tsunami warning system because many people had
underestimated their personal risk and/or assumed that the tsunami would be as small as others previously experienced.

Question 34

what happened after the chernobyll incident in 1986

Answer 34

thyroid cancer cases among children started to increase rapidly after four to five years had passed.
some are of the opinion that because of the Fukushima disaster, a similar increase in the incident of juvenile thyroid cancer
may occur.

Question 35

how much did the damage cost

Answer 35

estimated at $300 bill. making it the most
costly disaster in history

Question 36

tsunami

Answer 36

a major secondary consequence of the Tohoku earthquake

Question 37

magnitude of foreshock 2 days before the major earthquake

Answer 37

7.2

Question 38

how long did it take to repair a motorway damaged by the tsunami

Answer 38

6 days

Question 39

what plat boundary caused the EQ

Answer 39

destructive/convergent

Question 40

date of the earth quake

Answer 40

9 march 2011

Question 41

distance of the coast of japan from the epicentre

Answer 41

70km

Question 42

what powerplant was badly damaged and was releasing radiation

Answer 42

fukushima

Question 43

what % of Japan has sea walls; but they were too small for the tsunami

Answer 43

40%