Journal #73
What scale is used to measure magnitude?
What scale is used to measure intensity
Danger of Earthquakes
Movement of the ground during an earthquakeseldom directly causes many deaths andearthquakes.
Instead, most injuries result from the collapse ofbuildings, falling objects and flying glass.
Other dangers include landslides, fires, explosions,floodwaters from collapsing dams.
Tsunamis
Tsunami- giant ocean waves that forms after avolcanic eruption, earthquake, or landslide.
The waves cause serious destruction when itcrashes into land
A tsunami begins to form when a sudden drop orrise in the ocean floor
Destruction of Buildings
Most building are not designed to withstand themotion caused by earthquakes
Tall buildings may sway violently and can tip over.
The type of ground beneath a building can affectthe way in which the building responds to seismicwaves.
Destruction of Buildings
A building constructed on loose soil is muchmore likely to be damaged.
The loose soil can vibrate like jelly.
Building on top of this kind of groundexperience exaggerated motion and swayviolently.
Safety
A destructive earthquake may take place in any regionof the US.
However, destructive earthquakes are more likely tooccur in certain areas such as California or Alaska.
People who live near active faults should be ready tofollow earthquake safety rules.
Before an earthquake, be prepared with canned food,bottled water, flashlights, batteries etc.
Safety
During an earthquake, stay calm and move to asafe position.
Stand in the doorway or crouch under a desk/tableto protect yourself from falling debris.
If you are in a car what should you do?
After an earthquake, be cautious
Check for fires and hazards,
Warnings and Forecasts
Scientists have identified zones of low earthquakeactivity or siesmic gaps along some faults.
A siesmic gap is an area along a fault where fewearthquakes have occurred recently, but where strongearthquakes occurred in the past.
These are likely the locations of future earthquakes.
Warnings and Forecasts
Some earthquakes are preceded by littleearthquakes called foreshocks
They can precede an earthquake by a few secondsor a few weeks.
Scientists use a variety of sensors to detect slighttilting of the ground to identify strain and cracksin rocks caused by stress at fault zones.
Not all earthquakes have foreshocks or otherrecursors
Earthquake prediction is unreliable.
Scientist have been able to determine areasthat have a high earthquake hazard level.
Scientists continue to study seismic activityso that they many be able to make accurateforecasts and save more lives.
Your Assignment
Create a book or brochure that provides informationon earthquake safety.
See Rubric
Include pictures and lots of color!