Ms. Kee                                                                                Matt D and Reid P                                                                                 

EARTHQUAKES

 

An earthquake is a large or small shaking in the Earth. It’s a sudden movement of the Earth, an energy release. This movement of the Earth can be very strong. It is a dislocation of the Earth’s crust. This “dislocation” takes place on plate boundaries, where plates move away and towards each other. Sometimes these small earthquakes are called tremors, or temblors. In Japan, people used to believe earthquakes were pranks of a gigantic catfish. In Greek legend, the Sea God, Poseidon, would hit the sea floor with his trident and that would create earthquakes.

 

The shifting of underground plates can make a volcano or an earthquake. Earthquakes can occur in the middle of two plates. When two plates meet there is a sudden movement that can make an earthquake.

            In the Pacific Ocean many tremors are found because a lot of plates meet there. Also temblors can occur on a plate where there might be a weakness. A fault or crack in the plate might appear.

            An earthquake can occur near a volcano because there is a lot of plate movement. A fault can be a weakness in a plate that can trigger an earthquake. When new parts of the Earth’s crust are formed, earthquakes can occur.

 

            Earthquakes can also spawn other dangerous events. Sub­duction, a process where one plate slides beneath another, can also cause an earthquake. If the quake is underwater, it might also cause a tsunami. A tsunami is a gigantic wall of water that crashes into the shoreline of a place. Earthquakes usually create tsunamis. Also tremors can break dams or levees, which can then cause flooding. They also can make mudslides or landslides. Water mains can get broken. Also gas pipes can be broken and can then make fires. If water mains are broken, then it’s impossible to use water to put out the fires. Fires can start when broken gas pipes or power lines fall down. Power lines can fall on people and electrocute them. Earthquakes can be very powerful and dangerous. They can knock down buildings and destroy railroads, roads, bridges, and tunnels.

 

            Tremors can occur where two plates meet. The space between the two plates is called a fault. Plates, in fact, are not actually dining plates but gigantic pieces of rock that float on liquid rock called magma. Plates move very slowly. When two plates meet they will lock and pressure will build. When they slip they will release the energy and make a tremor. Tremors can occur in a convergent plate boundary. That’s where two plates collide and eventually slip. They also can occur in a divergent plate boundary, where two plates move away from each other. They might occur in a subduction plate boundary, too. That’s where two plates collide and one goes underneath the other. They will get stuck, then slip, releasing a lot of energy and causing a tremor. The last place a tremor can occur is in a transform boundary. Two plates slide past each other grinding the plates and creating a lot of energy.

            Part of the job of a seismologist is to locate the epicenter of a temblor. The epicenter is the spot on the surface directly above the focus of the temblor. They also study earthquakes by measuring them. One way to measure a temblor is to measure its intensity.  To measure intensity seismologists use a machine called a seismograph. A seismograph can record the vertical or horizontal movements of the earth. The readout created by the seismograph is called a seismogram. It shows the movement of the ground.  Another way to measure a temblor is to measure its magnitude or strength. Seismologists use the Richter scale to measure the magnitude. The scale is based on a 1-10 rating. If an earthquake is small its rating is going to be from 1-4; 5-7 are the ratings for a medium tremor. A major temblor would be rated from 8-10. 

        

            There have been a lot of bad earthquakes in history. One of them was the 1906, San Francisco tremor. The earthquake was a 7.1 on the Richter scale. It caused terrifying fires that couldn’t be controlled because water mains were broken. The longest earthquake in history took place in Anchorage Alaska on March 27, 1964. It lasted for four minutes and was an 8.5 on the Richter scale. It killed 50,000 people. In 1960 a 9.5 quake hit Chile; it was the strongest on record. In 1999 a 7.4 tremor hit Turkey and killed 17,000 people. In 2002 a temblor that rated 4.2 on the Richter scale hit the UK and lasted for 30 seconds. In 2004 a seaquake spawned a massive tsunami that slammed into coastlines across Asia, killing thousands of people.

          

            During a temblor it is best to stay indoors if possible because temblors can be very dangerous. Buildings, if they are constructed properly, can provide good protection especially if you stand in a doorway or are under a table. Those two spots offer good protection because they cover you and are very strong. Another good thing about staying inside is that foundations of houses are now being built with rubber in them so that they sway instead of shatter during a temblor. The rubber is able to absorb the temblor’s force. It is also handy to have a safety kit around; one with food, working batteries, unscented bleach, etc. If you are caught outside, try to get to an open area and be careful to stay away from power lines which could fall down and electrocute you.  A better warning system would also save lives.

            Although tremors destroy a lot and can be dangerous, they can also be beneficial.  Without earthquakes the land would be flat and swampy.  Tremors can cause volcanic activity which brings minerals to the soil making it fertile.  Tremors also make people have more advanced technologies.  They make people try to create efficient machines to measure earthquakes which create more jobs.  One of the best things about earthquakes is that they make people think more about their safety. Maybe Mother Nature created earthquakes for a reason. Temblors don’t have to be so bad.          

           

 

 

Bibliography

By: Matt D and Reid P                        

 

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Yardley, Jim.  China Resolves a Water Crisis in the North, then Pivots to a Major Earthquake in the South.”28 Nov. 2005.  The New York Times. December 21, 2005.  http://www.nytimes.com/2005/11/28/international/asia/28china.html

           

Gollner, Philipp.  “Scientists To Get Close View Of San Andreas Fault”.  12/7/2005. Yahoo.  12/21/05.  http://news.yahoo.com/s/nm/20051207/sc_nm/quake_sanandreas_drj_ylt=AqVHYsesnI1_.

   

Kostel, Ken.  “How Did This Happen?” Science World. 12 Dec.  2004

 

Schiermeier, Quirin.  “The Chaos To Come.” Nature.  12 Dec.  2005

 

Thomas, Evan. Wehrifritz, George. “Tide Of Grief.”  Newsweek 1,  Jan, 2005