Related topics: tectonic plates , tsunami , quake , san andreas fault , seismic activity
Earthquake
hideAn earthquake (also known as a tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are recorded with a seismometer, also known as a seismograph. The moment magnitude of an earthquake is conventionally reported, or the related and mostly obsolete Richter magnitude, with magnitude 3 or lower earthquakes being mostly imperceptible and magnitude 7 causing serious damage over large areas. Intensity of shaking is measured on the modified Mercalli scale.
At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacing the ground. When a large earthquake epicenter is located offshore, the seabed sometimes suffers sufficient displacement to cause a tsunami. The shaking in earthquakes can also trigger landslides and occasionally volcanic activity.
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. Earthquakes are caused mostly by rupture of geological faults, but also by volcanic activity, landslides, mine blasts, and nuclear experiments. An earthquake's point of initial rupture is called its focus or hypocenter. The term epicenter refers to the point at ground level directly above the hypocenter.
For more information about Earthquake, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with earthquake
Hawaiian hot spot has deep roots
Space & Earth / Earth Sciences
Dec 03, 2009 |
4.9 / 5 (11) |
1
(PhysOrg.com) -- Hawaii may be paradise for vacationers, but for geologists it has long been a puzzle. Plate tectonic theory readily explains the existence of volcanoes at boundaries where plates split apart ...
Deep creep means milder, more frequent earthquakes along Southern California's San Jacinto fault
Space & Earth / Earth Sciences
Nov 08, 2009 |
3.8 / 5 (6) |
1
With an average of four mini-earthquakes per day, Southern California's San Jacinto fault constantly adjusts to make it a less likely candidate for a major earthquake than its quiet neighbor to the east, the ...
Earthquakes actually aftershocks of 19th century quakes
Space & Earth / Earth Sciences
Nov 04, 2009 |
4.4 / 5 (19) |
13
(PhysOrg.com) -- When small earthquakes shake the central U.S., citizens often fear the rumbles are signs a big earthquake is coming. Fortunately, new research instead shows that most of these earthquakes ...
Australian continent to blame for Samoa, Sumatra quakes
Space & Earth / Earth Sciences
Oct 08, 2009 |
4 / 5 (5) |
0
(PhysOrg.com) -- The recent earthquakes in the Pacific and Indonesia have one University of Queensland researcher questioning whether the two are related.
Major quakes can weaken seismic faults far away, scientists say
Space & Earth / Earth Sciences
Sep 30, 2009 |
4.9 / 5 (8) |
0
(PhysOrg.com) -- U.S. seismologists have found evidence that the massive 2004 earthquake that triggered killer tsunamis throughout the Indian Ocean weakened at least a portion of California's famed San Andreas ...
New design keeps buildings standing and habitable after major earthquakes (w/ Video)
Sep 02, 2009 |
4.8 / 5 (4) |
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A new earthquake-resistant structural system for buildings, just successfully tested in Japan, will not only help a multi-story building hold itself together during a violent earthquake, but also return it ...
Acute impact on brain function in earthquake survivors
Medicine & Health / Psychology & Psychiatry
Aug 31, 2009 |
3.3 / 5 (4) |
1
New research has found that the Wenchuan, China earthquake that occurred on 12 May 2008 had an acute impact on the brain function of physically healthy survivors and poses a risk to the mental health of these survivors. The ...
Listening to rocks helps researchers better understand earthquakes
Space & Earth / Earth Sciences
Aug 17, 2009 |
5 / 5 (7) |
0
(PhysOrg.com) -- When Apollo punished King Midas by giving him donkey ears, only the king and his barber knew. Unable to keep a secret, the barber dug a hole, whispered into it, "King Midas has donkey ears," ...
A New Cloaking Method: This is not a 'Star Trek' or 'Harry Potter' Story (w/ Video)
Aug 17, 2009 |
4.4 / 5 (13) |
5
(PhysOrg.com) -- University of Utah mathematicians developed a new cloaking method, and it's unlikely to lead to invisibility cloaks like those used by Harry Potter or Romulan spaceships in "Star Trek." Instead, ...
Shaking the Earth: How Water Helps Tectonic Plates Slide in New Zealand
Space & Earth / Earth Sciences
Aug 05, 2009 |
4 / 5 (6) |
1
(PhysOrg.com) -- New Zealand is the site of one of the world’s youngest subduction zones, where the Pacific Plate of Earth’s crust dives beneath the Australian Plate. Now, a University of Utah study shows ...
Extraterrestrial platinum was 'stirred' into the Earth
Space & Earth / Earth Sciences
Jul 30, 2009 |
4.6 / 5 (10) |
3
(PhysOrg.com) -- A research program aimed at using platinum as an exploration guide for nickel has for the first time been able to put a time scale on the planet’s large-scale convection processes.
Massive quake moves NZealand closer to Australia
Space & Earth / Earth Sciences
Jul 22, 2009 |
4.7 / 5 (10) |
4
A massive 7.8 magnitude earthquake last week has moved the south of New Zealand closer to Australia, scientists said Wednesday.
Pacific tsunami threat greater than expected
Space & Earth / Earth Sciences
Jul 20, 2009 |
4.3 / 5 (8) |
0
The potential for a huge Pacific Ocean tsunami on the West Coast of America may be greater than previously thought, according to a new study of geological evidence along the Gulf of Alaska coast.
Contrary to recent hypothesis, 'chevrons' are not evidence of megatsunamis
Space & Earth / Earth Sciences
Apr 29, 2009 |
4.7 / 5 (3) |
0
A persistent school of thought in recent years has held that so-called "chevrons," large U- or V-shaped formations found in some of the world's coastal areas, are evidence of megatsunamis caused by asteroids ...
Solomon Islands earthquake sheds light on enhanced tsunami risk
Space & Earth / Earth Sciences
Apr 09, 2009 |
4.1 / 5 (8) |
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The 2007 Solomon Island earthquake may point to previously unknown increased earthquake and tsunami risks because of the unusual tectonic plate geography and the sudden change in direction of the earthquake, ...
