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?

fire

These 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 plan

Have 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?