What is an Earthquake?
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It all comes down to stress and strain. It is not 'the plates rubbing together' as many people say; or at least that's a very simplistic view.\n\nPlate tectonics causes stress on the continents and oceans, all over the surface of the earth. In some places, the stress is very small (usually within the plates). Elsewhere, the stress is high, usually where the plates meet each other. Since each plate moves, when two come in contact, the stress each other. They can push on each other and cause compressional stress, they can pull with extensional stress, and they can slide past or shear each other with tensional stress.\n\nFaulting, causing earthquakes, comes from the fact that this stress is building up all the time, but rocks and continents are strong materials. Just like hitting a rock with a small hammer, you do put stress on it, but a small amount. It would take a sledgehammer to put enough strain (effects and accumulation of stress) to build up and cause breakage. In the earth, the area around an active fault builds up strain from the stress of plate tectonics. Most faults become locked, because of this strength, and thus can not release their strain. Away from the fault, the stress produces very small and slow movement of the rock masses as a whole. Eventually, the strain is too much and the rest of the plate has moved too far and the fault releases the strain build-up all at once in a big stress release called an earthquake. This is called the elastic rebound theory, and it explains most (but not all) movements.\n\nThis is why an earthquake's size is relative to the fault size. The bigger the fault, the bigger the strain build up, and the bigger the release in an earthquake. Subduction zones and collision zones, where large portions of plates actually can rub together as a whole, have the really big earthquakes, like the 2004 Sumatra earthquake. In other plate boundaries, the entire plate boundary does not act together, so the faults become spread out and many faults take up the strain from the tectonic stress, like with the San Andreas Fault in California (it only takes up ~3/4 of the stress between the plates).\n\nEarthquakes are really tricky things; there is still so much we need to learn. As of now, there is no way to predict them, but we can say where the danger is highest and about how long between events.
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an earthquake happens when tectonic plates move\n\nmountains happen when tectonic plates overlap
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In the sense of an earthquake, yeah.  That's what it is.  A wave of earth moving out from the central point of origin.  That has nothing to do with the wave-particle duality.  In fact, it's best not to think of it as an actual wave or an actual particle (like a billiard ball).
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Earthquake not earthquek.\n\nAn earthquake is a sudden and sometimes catastrophic movement of a part of the Earth's surface. Earthquakes result from the dynamic release of elastic strain energy that radiates seismic waves. Earthquakes typically result from the movement of faults, planar zones of deformation within the Earth's upper crust. The word earthquake is also widely used to indicate the source region itself. The Earth's lithosphere is a patch work of plates in slow but constant motion (see plate tectonics). Earthquakes occur where the stress resulting from the differential motion of these plates exceeds the strength of the crust. The highest stress (and possible weakest zones) are most often found at the boundaries of the tectonic plates and hence these locations are where the majority of earthquakes occur. Events located at plate boundaries are called interplate earthquakes; the less frequent events that occur in the interior of the lithospheric plates are called intraplate earthquakes (see New Madrid Seismic Zone). Earthquakes also occur in volcanic regions and as the result of a number of anthropogenic sources, such as reservoir induced seismicity, mining and the removal or injection of fluids into the crust. Seismic waves including some strong enough to be felt by humans can also be caused by explosions (chemical or nuclear), landslides, and collapse of old mine shafts, though these sources are not strictly earthquakes.
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A response spectrum shows the response of a series of oscillators activated during an earthquake. The spectrum response method is commonly used to predict potential damage to structures in areas likely to be affected by earthquakes.
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earthquakes occur when the tectonic plates that cover the earth noticably shift. These movements can also form volcanoes and trenches
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The tectonic plates were already broken before oil was drilled, it has always been that way since the earth cooled. Oil drilling is not the reason earthquakes exist.
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Yes! That is what causes all earthquakes!\n\nIt is a conspiracy!
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hypocenter\nlearn more at\nhttp://earthquake.usgs.gov/learning/facts.php
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one cannot predict earthquakes, but due to the behavorial changes or sounds made by birds or other animals we can just become aware and alert about the possibility of an earthquake. also if some underground animals start coming out of their holes it means an earthquake can occur because they have very good sensing organs and can sense the frequencies matching that of an earthquake.
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Following an earthquake you should examine your home for potentially dangerous objects that may have fallen or become loose.  Broken objects can be hazardous when stepped on and loosened object can later fall on people.  It is also a good idea to examine your foundation for cracks.
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Energy is produced when an earthquake occurs. This energy is released in the form of seismic waves. These waves travel throughout the entire Earth. Waves transmit energy between different points. There are many kinds of waves, seismic waves are a type of physical wave. \nhttp://msnucleus.org/membership/html/k-6/pt/earthquakes/3/pte3_1a.html
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The most famous episode of a human-induced earthquakes began in 1961, when a 3600 meter (12,000 feet) deep disposal well was drilled in the United States Army's Rocky Mountain Arsenal northeast of Denver, Colorado. The well was used for disposing of toxic waste fluids from nerve gas production, and injection commenced in March 1962.\n\nShortly thereafter an unusual series of earthquakes erupted in the area, and by the end of December 1962 about 190 earthquakes had occurred. None caused damage until December, when several structures were damaged in Dupont and Irondale.\n\nOver 1,300 earthquakes were recorded between January 1963 and August 1967. In April 1967 the largest earthquake since the series began in 1962 occurred, and damage was recorded in the arsenal, Derby and Boulder. This tremor measured 5.0 on the Richter scale.\n\nEven after the Rocky Mountain Arsenal waste dumping practice stopped, earthquakes continued to be felt in the Denver area, so in 1968 the Army began removing fluid from the arsenal well very slowly in an effort to reduce the earthquake activity.
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is this what your talking about\n\n\nAn earthquake is a phenomenon that results from and is powered by the sudden release of stored energy that radiates seismic waves. At the Earth's surface, earthquakes may manifest themselves by a shaking or displacement of the ground and sometimes tsunamis, which may lead to loss of life and destruction of property.\n\nEarthquakes may occur naturally or as a result of human activities. In its most generic sense, the word earthquake is used to describe any seismic event—whether a natural phenomenon or an event caused by humans—that generates seismic waves\n\nEarth (often referred to as "The Earth") is the third planet in the solar system in terms of distance from the Sun, and the fifth in order of size. It is the largest of its planetary system's terrestrial planets and the only place in the universe currently known to support life. The Earth was formed around 4.57 billion (4.57×109)[1] years ago (see Age of the Earth) and its largest natural satellite, the Moon, was orbiting it shortly thereafter, around 4.533 billion years ago.\n\nSince it formed, the Earth has evolved through geologic and biological processes so that any traces of the original conditions have been virtually eliminated. The outer surface is divided into several tectonic plates that gradually migrate across the surface over geologic time spans. The interior of the planet remains active, with a thick layer of molten mantle and an iron core that generates a magnetic field. The atmospheric conditions have been significantly altered by the presence of life forms, which create an ecological balance that modifies the surface conditions. About 70% of the surface is presently covered in salt water oceans, and the remainder consists of continents and islands.\n\nThere is significant interaction between the Earth and the space environment. The relatively large Moon provides ocean tides and has gradually modified the length of the planet's rotation period. A cometary bombardment during the early history of the planet is believed to have formed the oceans. Later, asteroid impacts are understood to have caused significant changes to the surface environment. Changes in the orbit of the planet may also be responsible for the ice ages that have covered significant portions of the surface in glacial sheets.\n\nThe Earth does not have another natural orbiting body other than the Moon, although Cruithne has been erroneously described as such. Cruithne was discovered in 1986 and follows an elliptical orbit around the Sun at about the same average orbital radius as the Earth. However, from the point of view of the moving Earth, Cruithne follows a horseshoe orbit around the Sun that avoids close proximity with the Earth.
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You won't be warned.  The earth will just start moving.  The danger isn't the earthquake.  The dangers are the things that fall on you, the fires that burn after (assuming gas lines or electricity or some source of fire and fuel).
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Definition of tsunami: An ocean wave produced by a sub-marine earthquake, landslide, or volcanic eruption. These waves may reach enormous dimensions and have sufficient energy to travel across entire oceans.\n\nThe first link below is a site dedicated to tsunamis. Check it out.
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A seismograph measures the strength and direction of earthquake waves. It records the tremors and compares their strengths on the Richter scale. A scale of one is a minor earthquake, while a scale of seven is severe.