examples! Flashcards
earthquake hazard: GROUNDSHAKING
2010 HAITI
- P: destroyed >250,000 houses
- S: water pipes ruptured, water shortage + contamination
- L: killed >220,000 people, river pollution (waterborne diseases —> death)
earthquake hazard: SOIL LIQUEFACTION
2010 CHRISTCHURCH (lies on former swamp)
- P: >60,000 residential buildings damaged (1/3 city)
- N: entered rivers, untreated sewage polluted rivers —> decrease in species (caddisflies)
earthquake hazard: LANDSLIDES
2018 PAPAU NEW GUINEA
- N: debris in rivers —> floods
—> destroyed forests, polluted rivers, killed aquatic life
earthquake hazard: TSUNAMI
2011 TOHOKU JAPAN
- P: waves 40m in height, infrastructure destroyed
- L: coastal city SENDAI, JAPAN — HALF population killed by tsunami & earthquake
- N: 70,000 pine trees washed away
—> PACIFIC ISLANDS (Midway Atoll): Layson albatross chicks killed, nesting sites lost
recap!
1. undersea earthquake — SEABED DISPLACED :(
2. large vol of water LIFTED —> waves of great wavelength & low height form
3. travel at HIGH speeds toward land (800km/h)
4. GREATER FRICTION between shallower seabed near the coast — slows waves
5. INCREASE in HEIGHT (30-50km/h)
volcanic hazards: TEPHRA
1991 MT PINATUBO
- S: millions of tonnes of ash, 10 million tonnes of lava, 20 million tonnes of SO2
—> closure of 7 airports in the philippines
- L: wet ashfall accumulation on roofs — accounted for most deaths
- N: destroyed 800 square km of rice fields
volcanic hazard: VOLCANIC GASES
1991 MT PINATUBO
- 20 million tonnes of SO2
volcanic hazard: LAVA FLOWS
2018 MT KILAUAE, HAWAII
- P: destroyed >600 homes
—> huge areas of forests damaged
- N: forest & biodiversity loss, habitats etc
volcanic hazard: PYROCLASTIC FLOWS
2010 MT MERAPI
- P: traveled 3km down sides, destroyed property
- L: 350 killed, burn and blast
volcanic hazard: LAHARS
1991 MT PINATUBO
- P: buried villages & farmland (esp during heavy rainfall periods years after)
- 800,000 heads of livestock killed
- displaced many people
1985 NEVADO DEL RUIZ, COLOMBIA
- P: 500 homes destroyed, 60% livestock gone
- S: roads, telephone lines, buildings all destroyed, swept away
- L: fast-flowing lahars killed >20,000 within seconds
volcanic hazard: VOLCANIC LANDSLIDES
1980 MT ST HELENS, USA
- N: north face collapsed
—> 50-80m/s, travelled more than 20km
volcanic benefits: FERTILE SOIL
MT AGUNG, BALI
- volcanic rocks break down, undergo weathering to form fertile soil
- best rice-growing regions are new volcanoes, income for locals
volcanic benefits: PRECIOUS MINERALS & FOSSIL FUELS, CONSTRUCTION MATERIALS
MT MERAPI, INDONESIA
- mine volcanic sand for construction
(employment opportunities for locals)
volcanic benefits: PRECIOUS MINERALS & FOSSIL FUELS, CONSTRUCTION MATERIALS
MT MERAPI, INDONESIA
- mine volcanic sand for construction
(employment opportunities for locals)
volcanic benefits: HARNESSING GEOTHERMAL ENERGY
ICELAND
- mostly powered by geothermal energy, generates 25% of country’s energy
volcanic benefits: TOURISM
HAWAIIAN ISLANDS
- US$88 million annual income
- thousands of jobs
earthquake disaster risks: NATURE
- duration
- time
nature of earthquake: DURATION
2011 TOHOKU (Mw 9.0)
- lasted 6min
- massive damage to buildings
nature of earthquakes: TIME
1995 KOBE JAPAN (Mw 6.9)
- 6am earthquake
- asleep —> trapped —> 6,000 lives lost
vulnerable conditions of earthquakes: QUALITY OF BUILDING DESIGN & CONSTRUCTION
2010 HAITI (Mw 7.0)
- poor quality, poorly reinforced & unregulated
- >90% buildings near epicentre destroyed
- 220,000 deaths
VS
2011 TOHOKU (Mw 9.0)
- skyscrapers with hazard resistant features SWAYED, did not collapse
(engineered to withstand)
vulnerable conditions of earthquakes: SOIL & ROCK PROPERTIES
2010 HAITI
- lies on soft soil — seismic waves AMPLIFIED
- collapse of many buildings
—> soil liquefaction
exposure of earthquakes: POPULATION DENSITY
2010 PORT AU PRINCE HAITI
- densely populated
1995 KOBE (6.9)
- 3,000 ppl per km2
- killed >6,000, injured >40,000
exposure of earthquakes: DISTANCE FROM EPICENTRE
2010 HAITI
- 25km west of port au prince
- 220,000 deaths
nature of volcanoes: CHEM COMPOSITION OF MAGMA
[LOW SILICA] 2018 MT KILAUAE, HAWAII
- >700 homes destroyed, property damage: US$800 million
[HIGH SILICA] 2010 MT MERAPI
- pyroclastic flows — traveled 3km down heavily populated sides
- volcanic bombs — 10km distance
- evacuation of 350,000 ppl
vulnerable conditions of volcano: AVAILABILITY OF SURFACE & GROUNDWATER
1991 MT PINATUBO
- lahars triggered during monsoon season
- >100,000 homes destroyed
