Earthquakes :: essays research papers

Earthquakes Earthquakes occur almost e actuallyday either everyplace the world. Most of the time quakes are not strong enough to be felt by people, but the shaking subjectd by an earthquake sess be recorded by a seismometer. These machines are located all over the world to ensure detection of earthquakes of all strengths. Only once in a while will a larger magnitude earthquake strike and cause damage to the region. There are many faults around the world and depending on where these faults are plays a major factor in determining where an earthquake will occur. It is these faults that are the reason for earthquakes. The information seismologists know about recent earthquakes and earthquakes in general give them a limited ability to in the main predict when and where earthquakes are going to occur. An earthquake is the shaking of Earths surface caused by rapid movement of the earths uptight outer layer. Earthquakes occur when tension stored in rocks suddenly releases (Vogt 12) . sacks occur at these places where rocks on either side of the crack have moved. Oceans are very prevalent places for major tectonic plates to shift. When 2 plates separate, new oceanic rancour is made near the fault as magma rises and eventually sets on the sea floor. If the plates on either side of the fault continue to spread consequently the ocean slowly becomes larger in width. This is called seafloor spreading. Mid-ocean ridges are characterized by a crack like vale at the fault. This crack like valley is caused by the tension pulling the plates apart, cause normal faulting to occur a number of times in the divergent boundary. Shevchik 2The most common vitrine of fault is a normal or dip-slip fault. These occur when two blocks of earth are thrust toward each other, causing one to take up over the other (Britt 1). The intermission wall moves downward congress to the footwall (Tarbuck 244). A reverse fault is the opposite of a normal fault. The hanging wall moves upw ard relative to the footwall (Tarbuck 244). A very powerful persona of fault is the strike-slip fault that occurs when two plates slide past one another. The San Andreas Fault in California is a very good example of this typesetters case of fault. A great deal of damage is done when any type of fault shakes the soil under structures in a low-lying, waterlogged areas, causing liquefaction. Liquefaction occurs when an earthquake shakes the wet, sandy soil near a body of water.