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 earthquake seldom directly causes many deaths and earthquakes. Instead, most injuries result from the collapse of buildings, falling objects and flying glass. Other dangers include landslides, fires, explosions, floodwaters from collapsing dams.

Tsunamis Tsunami- giant ocean waves that forms after a volcanic eruption, earthquake, or landslide. The waves cause serious destruction when it crashes into land A tsunami begins to form when a sudden drop or rise in the ocean floor

Destruction of Buildings Most building are not designed to withstand the motion caused by earthquakes Tall buildings may sway violently and can tip over. The type of ground beneath a building can affect the way in which the building responds to seismic waves.

Destruction of Buildings A building constructed on loose soil is much more likely to be damaged. The loose soil can vibrate like jelly. Building on top of this kind of ground experience exaggerated motion and sway violently.

Safety A destructive earthquake may take place in any region of the US. However, destructive earthquakes are more likely to occur in certain areas such as California or Alaska. People who live near active faults should be ready to follow 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 a safe position. Stand in the doorway or crouch under a desk/table to 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 earthquake activity or siesmic gaps along some faults. A siesmic gap is an area along a fault where few earthquakes have occurred recently, but where strong earthquakes occurred in the past. These are likely the locations of future earthquakes.

Warnings and Forecasts Some earthquakes are preceded by little earthquakes called foreshocks They can precede an earthquake by a few seconds or a few weeks. Scientists use a variety of sensors to detect slight tilting of the ground to identify strain and cracks in rocks caused by stress at fault zones.

Not all earthquakes have foreshocks or other recursors Earthquake prediction is unreliable. Scientist have been able to determine areas that have a high earthquake hazard level. Scientists continue to study seismic activity so that they many be able to make accurate forecasts and save more lives.

Your Assignment Create a book or brochure that provides information on earthquake safety. See Rubric Include pictures and lots of color!