Seismic hazard case studies Flashcards
Japan Earthquake: When
2011
Japan Earthquake: Details 5
- 9.0 magnitude
- The fourth most powerful earthquake ever detected worldwide.
- Epicentre = 130 km east of the city of Sendai Focus = 15.5 miles below the floor of the Pacific Ocean
- Aftershocks continued, many exceeding magnitude 7.0.
Japan Earthquake: Primary impacts 2
- Life loss from the earthquake relatively small and few buildings collapsed.
- Roads and rail lines damaged
Japan Earthquake: Secondary short-term impacts 9
- Tsunami waves caused by sudden horizontal and vertical thrusting of the Pacific Plate, displacing the water above it.
- A wave 40m high inundated the coast and flooded parts of Sendai (+airport)
- so strong that it generated waves 11 to 12 ft high along the coasts of Kauai and Hawaii
- 19,300 people died
- A wave flooded Fukushima’s plant generators and electrical wiring.
- People lost energy immediately.
- 330,000 buildings destroyed 300 hospitals damaged
- around 4.4 million households in North-East Japan were left without electricity.
- Some areas experienced land subsidence
– dropped the beachfronts by 50 cm.
Japan Earthquake: Secondary long-term impacts 3
- US$235 billion
the most expensive natural disaster in world history
- damage caused by the earthquake resulted inmeltdown of seven reactors.
- Radiation levels at one point eight times normal levels.
- 1 million households had no water
Japan Earthquake: Prediction, Prep, Planning 5
- Buildings: Japan has the technology to invest in ‘life safe’ structures
- . Seismic isolators, counterbalances and cross bearings help to keep structures from pancaking when the p and s waves strike. Around 87% of buildings in Tokyo are able to withstand earthquakes.
- Warning system: Every smartphone in Japan is installed with an earthquake and tsunami emergency alert system - the warning systems detects the s waves from earthquakes Trains: The trains are equipped with earthquake sensors that are triggered to freeze every moving train in the country if necessary. When the quake hit, there were 27 moving bullet trains in action. Every single train was triggered by smaller pre-quakes and stopped before the major quake hit, resulting in zero deaths or even injuries. Education: From a young age, schoolchildren are educated on the best way to seek protection and stay safe if an earthquake hits their area. Sea Wall: Japan spent billions of dollars building anti-tsunami defenses at heights of 12 m. The tsunami washed over them, rendering them totally ineffective. HOWEVER, in Fudai - the late mayor built a 17m tall sea wall in the 1970s after seeing the devastation of the 1933 Tsunami that hit the area - this wall saved the small town and it was left untouched compared with neighbouring towns which were destroyed.
Japan Earthquake: Immediate responses 7
- 100,000 members of the Japanese Self-Defense Force were rapidly mobilized to deal with the crisis
- Japanese government requested that U.S. military personnel stationed in the country be available to help in relief efforts
- Hampered initially by the difficulty in getting personnel and supplies to the devastation zone
- The majority of the 270,000 persons within the nuclear evacuation zone were evacuated
- Within a week: Roads leading to coastal towns were cleared
- All 14 ports were restored to receive relief goods.
- Electric service was restored to 90% of Japan’s residents.
Japan Earthquake: Long-term responses 6
- Within a month:
- Water service estored to 90% of residents.
- Train service was restored to the area, except for the destroyed coastal line In 2012: The government established a cabinet-level Reconstruction Agency to coordinate rebuilding efforts in the Tōhoku area. The agency was scheduled to be in operation for 10 years. In early 2015 the agency reported that nearly all the disaster debris had been removed. By 2018: 344,000 people were still displaced. About 92% of public housing units were completed. Evacuation orders continue to be lifted as communities in Fukushima were decontaminated and radiation levels normalised.
Haiti Earthquake: When
2010
Haiti Earthquake: Details 3
7.0 magnitude Epicentre = 25km away from Port au Prince Focus = 8.1 miles below the surface
Haiti Earthquake: Primary Impacts 4
- An estimated 250,000 people died
- At least 300,000 people were injured
- Nearly 4,000 schools were damaged or destroyed
- . 3 million people affected
Haiti Earthquake: Secondary impacts 6
- Over 1 million left homeless
- Haiti lacked any building codes - the buildings pancaked Infrastructure: The vital infrastructure necessary to respond to the disaster was damaged or destroyed - hospitals in the capital; air, sea, and land transport facilities; and communication systems.
- Looting became prevalent and was exacerbated in the capital by the escape of several thousand prisoners from the damaged penitentiary.
- Morgues: Survivors were forced to wait days for treatment and, with morgues quickly reaching capacity, corpses were stacked in the streets
- orphans left vulnerable to abuse and human trafficking.
- Cholera: I cases of cholera began to surface around the Artibonite River. as it had been contaminated by fecal matter
Haiti Earthquake: Immediate response 3
Efforts by citizens and international aid organizations to provide medical assistance, food, and water to survivors were hampered by the failure of the electric power system, loss of communication lines, and roads blocked with debris. A week after the event, little aid had reached beyond Port-au-Prince. The infrastructure of the country’s computer network was largely unaffected so electronic media emerged as a useful mode for connecting those separated by the quake and for coordinating relief efforts.
Haiti Earthquake: Long-term response 3
By spring and summer, reconstruction efforts had made little progress Two years later: Only half of the rubble littering Port-au-Prince had been cleared. More than half a million people remained in tents
