by: Makenna, Sydney, Lilyan, Alex

Definition of Earthquakes

Earthquakes: a sudden and violent shaking of the ground sometimes causing great destruction as a result of movements within the earth crust. (sydney)

why do they happen?: earthquakes are usually caused by rock underground that suddenly break along a fault line. This sudden release of energy cause the seismic waves that make ground shake when two blocks of rock or two plates are rubbing against each other. (sydney)

Location of Earthquakes

where do earthquakes happen?: most earthquakes happen along the edge of the oceanic and continental plates. (alex)

what are plate tectonics?: a they explaining the structure of the earth's crust and many associated phenomena as resulting from the interaction of rigid lithosphere plates that move slowly over the underlying mantle. (alex)

Measuring Earthquakes

how are earthquakes measured?: the vibration of an earthquake are detected and recorded by measuring an instrument called a seismograph. the zig zag line reflects the changing intensity of the vibrations. the two general types of vibrations are surface waves that travel along earths surface and body waves that travel through the earth. (sydney)

what is the name of the scale? what is their intensity?: their main scale is called the "richter magnitude scale", which was developed by Charles F. Richter. It's intensity is magnitude that was less than 3.5 which was generally not felt but recorded. (Makenna)

Earthquakes Major Fault Lines

What and where are the major fault lines in the united states and around the world?: the major fault line is located in the New Madrid Seismic zone, it's one of the main fault lines in both the United States and around the world. (Makenna)

What should you do to protect yourself during an Earthquake?: in most situations, you will reduce your chance of injury if you cover your hands and neck with both arms, clasping your neck with your hands. if a dest or table is nearby, crawl beneath it while keeping one arm over your head. you can also hold on to your shelter or your head and neck until the shaking stops. be prepared to move with your shelter if the shaking shifts it around.(lilyan)

research somemajo earthquakes that have occurred. tell about them:

1-July 27, 1976- China, Tongshan- 255,000 official-7.5 (estimated death at about 655,000)

2- december 26, 2004- Sumatra, indonesia-227,898- 9.1- deaths from earthquakes and tsunamis.

3- december 16, 1920- china,gansu- 200,000-8.6-major fractures,longslides

4-november 1, 1755- portugal , lisbon- 70,000-8.7- great tsunami.

5- may 31,1970- peru- 66,000-7.9-$530,000,000 worth of damage, great rock slide, and floods(lilyan)