Tectonics tsunami case studies

Question 1

Developing example

Answer 1

Indian Ocean

Question 2

Emerging example

Answer 2

Talcahuano (Chile)

Question 3

Developed example

Answer 3

Japan (same as earthquake)

Question 4

Developing date and time + mag

Answer 4

26th December 2004 (Boxing Day), 07:58
9.1

Question 5

Emerging date and time + mag

Answer 5

27th February 2010, 03:34
8.8

Question 6

Developed date and time + mag

Answer 6

11th March 2011, 14:26
9.1 (from 9.0)

Question 7

Cause of developing tsunami + focal depth

Answer 7

Megathrust at subduction zone caused 20m uplift (I-A under Eurasian)
30km

Question 8

Cause of emerging tsunami + focal depth

Answer 8

Megathrust at subduction zone (Nazca under SA)Cause of developing tsunami
35km

Question 9

Cause of developed tsunami + focal depth

Answer 9

Megathrust at subduction zone (Pacific under NA)
30km

Question 10

Features of developing tsunami

Answer 10

24m height
up to 800km/h speeds
inundated 3km inland

Question 11

Features of emerging tsunami

Answer 11

2.6m height
725km/h

Question 12

Features of developed tsunami

Answer 12

up to 10m height
inundated 10km inland
800km/h

Question 13

Indian Ocean social impacts

Answer 13

Fatalities in 14 countries
Over 200,000 deaths (tourism played a role)
1.7m homeless
Passenger train in Sri Lanka derailed- killed 1700 people (largest rail disaster in terms of life lost)

Question 14

Indian Ocean economic impacts

Answer 14

$15b in losses
60% Sri Lanka’s fishing industry destroyed as ports lost

Question 15

Indian Ocean environmental impacts

Answer 15

8m litres of oil escaped in Indonesia -> damaged coral reefs + coastal wetlands
crops + farming land destroyed
Salt water damaged freshwater ecosystems

Question 16

Talcahuano social impacts

Answer 16

525 deaths
370,000 homes destroyed
Supply shortages led to widespread looting in Concepción

Question 17

Talcahuano economic impacts

Answer 17

$15-30b losses
Insurance companies lost up to $8b
Ports destroyed
Power outages meant copper production halted for a day
Food prices tripled in some places

Question 18

Talcahuano environmental impacts

Answer 18

debris from buildings
Pipe damage meant unprocessed sewage released into Biobio river

Question 19

Japan social impacts

Answer 19

Over 15,000 deaths
122,000 homes destroyed
130,927 homeless
4000 roads destroyed

Question 20

Japan economic impacts

Answer 20

$240b losses
Power cuts so lack of business activity
46,000 buildings destroyed

Question 21

Japan environmental impacts

Answer 21

Radioactive chemicals leaked + found in Tokyo’s drinking water
5m tonnes debris in sea
Cracked a major iceberg in Antarctica

Question 22

Why was Indian Ocean vulnerable?

Answer 22

One of most powerful earthquakes recorded- felt in India
Mostly developing countries
Densely populated region
Coastlines low lying
Occurred during main tourist season
No warning system (except Thailand, but failed to function adequately)
Loss of mangroves e.g. due to prawn aquaculture

Question 23

Why was Talcahuano vulnerable?

Answer 23

Reaction of warning system not fast enough
Disproportionately killed tourists camping in low lying areas- locals evacuated to higher ground
Daylong blackout followed
Epicentre only 70 miles from urban area

Question 24

Why was Japan vulnerable

Answer 24

Very powerful earthquake
Particularly shallow offshore area = increased shoaling so taller wave
Islands diffracted waves, so took longer to reach other land masses = reduced impact there
Lowlands located on east coast
BUT had warning 3 minutes after earthquake = 20 mins to get to higher ground

Question 25

Why was Boxing Day tsunami considered mega-disaster?

Answer 25

14 countries impacted
required international aid
Large economic losses and deaths across countries

Question 26

Why was Japan tsunami considered mega-disaster?

Answer 26

Economic impacts had global consequences e.g. car supply chain disruptions
Loss of public acceptability of nuclear power-> countries e.g. Germany either shut down power plants or abandoned plans to build new ones

Question 27

Changes after Indian ocean tsunami

Answer 27

late 2006- DART system to detect future tsunamis (only 6 buoys in South Pacific prior to tsunami), now 60