Earthquake hazards
description
Transcript of Earthquake hazards
Earthquake hazards
Types of hazards Surface faultingGround shakingLandslides LiquefactionTsunamis
Pair share: if you see the tide go WAY out what should you do and why?
Surface faulting and ground shakingSurface faulting is when
a shallow earthquake causes the ground to split & shift
Ground shaking buildings can be damaged and the ground can shift. The intensity of the shaking
depends on: the magnitude and proximity of the earthquake & the soil type
Liquefaction When water
and soil are mixed, the ground becomes very soft & acts similar to quicksand Liquefaction can cause a
great deal of damage, especially in urban areas
If liquefaction occurs under a building, it may start to lean, tip over, or sink several feet.
Pair share: explain the diagram above to your partner.
Ground subsidence Ground subsidence is the lowering of the land
surfaceCaused by either liquefaction causing the settling
of sediment or movement along the fault
After before
landslides landslides occur on sloping land that is unstable they cause $1 billion and 25-50 deaths in the US
each year. Earthquakes, floods, and fires increase the hazard
Pair share: why do you think each of the 3 things listed above increase landslide hazard?
fireThese fires can
be started by broken gas lines and power lines, or tipped over wood or coal stoves.
They can be a serious problem, especially if the water lines that feed the fire hydrants are broken, too.
After the Great San Francisco Earthquake in 1906 most of the city was destroyed and 250,000 people were left homeless.
Hazard maps Used to predict:
where earthquakes are likely to occur
How much shaking there will be
Information used to make the map:Where faults areType of soil/rockEarthquake historyWhite board: What color is Sonoma on the map?
Be Prepared: Have an emergency kit
Have an emergency kitnonperishable food waterFirst aid kitFlashlight and batteries Radiocash
Be Prepared: Have a family planHave phone numbers of family members Know where the safest places in your home areHave an evacuation plan including where to meet Know where the gas and water lines are to your home
and how to shut them offMake your home earthquake safe: secure large objects &
keep heavy items on lower shelvesDo hang mirrors or other glass items over your bed
Whiteboard review 1. What is liquefaction?
2. Name 3 things you should have in an earthquake preparedness kit.
3. What do earthquake hazard maps tell us?