seismic hazards Flashcards
what are earthquakes
The release of slowly built up pressure between plate margins causing the Earth to shake
What is retrofitting
Earthquake proofing of buildings
What are tsunamis
Giant waves inland caused by the shock of an earthquake in the plate
What is soil liquefaction
When seismic vibrations cause the land to act like liquid
Primary effects of earthquakes
Ground shaking and ocean floor rupturing
Secondary effects of earthquakes
Soil liquefaction
Land slides
Tsunamis
Fires
Collapsing buildings
Which boundaries do earthquakes occur at
All of them
How many earthquakes does the ring of fire equate for
90%
How is the seismicity measured
Along the Richter scale from 0-10
What is the magnitude dependent on
The depth of the focus point
Which boundaries have the shallowest focus but strongest waves
Conservative
What is the frequency of earthquakes
Occur everyday
Examples of preparedness for earthquakes
Warning systems for tsunamis
Awareness strategies and education
Evacuation plans
Examples of preventing impacts of earthquakes
Soil stabilisation using poles to prevent liquefaction
Controlled explosives prevent avalanches
Examples of mitigation against earthquakes
Demolish and rebuild weak buildings
Tsunami sea walls
Turning services off to prevent fires
