Earthquake Destruction and Dangers http://embc.gov.bc.ca/em/hazard_preparedness/earthquake_photos.html

Major causes of earthquake damage Soil conditions Aftershocks Tsunamis

Soil conditions Layers of loosely packed soil, high in moisture can lead to Landslides Liquefaction

Landslides Landslides are movement of material down a slope. They can occur… when filled land is shaken violently where steep slopes are found

Liquefaction Loosely packed soil turns into mud. Most likely to occur in soil saturated with water.

Liquefaction Loosely packed soil turns into mud. Most likely to occur in soil saturated with water.

Aftershocks Smaller earthquakes that occur after a larger earthquake in the same area They can occur hours, days, or months later Buildings already weakened by the original earthquake can topple during aftershocks

Tsunamis A wave set off by an underwater earthquake Earthquake jolts the ocean floor; pushes water out of the way Displaced water forms large waves (tsunamis) In the open ocean, height of wave is not significant As the wave gets closer to land, water gets more shallow, pushes up into a tall wall ≈100 ft YouTube: Tsunami Animation YouTube: CBS News Asian Tsunami

http://news. nationalgeographic http://news.nationalgeographic.com/news/2011/03/pictures/110315-nuclear-reactor-japan-tsunami-earthquake-world-photos-meltdown/#/japan-earthquake-tsunami-nuclear-unforgettable-pictures-wave_33291_600x450.jpg

http://www. dailymail. co http://www.dailymail.co.uk/news/article-1366395/Japan-tsunami-earthquake-Rescuers-pick-way-apocalypse-wasteland.html

How do we prepare? Base-isolated buildings Buildings rest on shock absorbing springs that allow the building to move without violently shaking

Protecting Structures

How do we prepare? Base-isolated buildings Buildings rest on shock absorbing springs that allow the building to move without violently shaking Warning systems Monitoring faults and waves

Instruments for monitoring faults Faults & Earthquakes Creep meter measures HORIZONTAL movement along a fault line through movement of a wire across the fault Tiltmeter measures VERTICAL movement, works like a carpenter’s level Satellites Measure VERTICAL changes in the distance between the satellite and ground

Fault monitoring instruments Creep meter Tiltmeter

Instruments for monitoring tsunamis Tsunami detection buoys 39 stations collect seafloor height, temperature, pressure Warning centers If a tsunami is generated, they issue advisories, watches and warnings