earthquake

earth·quake

E0008500 (ûrth′kwāk′)n. A sudden movement of the earth's crust caused by the release of stress accumulated along geologic faults or by volcanic activity. Also called seism, temblor.

earthquake

(ˈɜːθˌkweɪk) n (Geological Science) a sudden release of energy in the earth's crust or upper mantle, usually caused by movement along a fault plane or by volcanic activity and resulting in the generation of seismic waves which can be destructive.

earth•quake

(ˈɜrθˌkweɪk)

n. 1. a series of vibrations induced in the earth's crust by the abrupt rupture and rebound of rocks in which elastic strain has been slowly accumulating. 2. something that is severely disruptive; upheaval. [1300–50]

earth·quake

(ûrth′kwāk′) A sudden movement of the Earth's crust. Earthquakes are caused by the release of built-up stress within rocks along geologic faults or by the movement of magma in volcanic areas. They are usually followed by aftershocks. See Note at fault.Did You Know? If all the dishes fall out of your cabinet, you may honestly be able to say, "It's the Earth's fault!" Indeed, the Earth has faults, cracks where sections of its outer shell (the lithosphere) slip past each other, causing an earthquake when subjected to great forces. Three kinds of waves accompany earthquakes. Primary (P) waves have a push-pull type of vibration. Secondary (S) waves have a side-to-side type of vibration. Both P and S waves travel deep into the Earth, reflecting off the surfaces of its various layers. S waves cannot travel through the liquid outer core. By contrast, surface (L) waves—a third type of wave, named after the 19th-century British mathematician A.E.H. Love—travel along the Earth's surface and do most of the damage associated with an earthquake. The total amount of energy released by an earthquake is measured on the Richter scale. On this scale, each increase by 1 corresponds to a tenfold increase in earthquake strength. Thus an earthquake measuring 5.0 on the Richter scale is 10 times stronger than one measuring 4.0. Earthquakes above 7 on the Richter scale are severe. The famous earthquake that flattened San Francisco in 1906 measured 7.8.

earthquake

A sudden shaking of the ground when stressed rocks move along a fault. Volcanic eruptions trigger some earthquakes.

Thesaurus

Noun	1.	earthquake - shaking and vibration at the surface of the earth resulting from underground movement along a fault plane of from volcanic activityquake, seism, temblorseismic disturbance, shock - an instance of agitation of the earth's crust; "the first shock of the earthquake came shortly after noon while workers were at lunch"earth tremor, microseism, tremor - a small earthquakeseaquake, submarine earthquake - an earthquake at the sea bedgeological phenomenon - a natural phenomenon involving the structure or composition of the earth
	2.	earthquake - a disturbance that is extremely disruptive; "selling the company caused an earthquake among the employees"commotion, hoo-ha, hoo-hah, hurly burly, kerfuffle, to-do, disruption, disturbance, flutter - a disorderly outburst or tumult; "they were amazed by the furious disturbance they had caused"

earthquake

noun earth tremor, quake (informal), tremor, seism the catastrophic Mexican earthquake of 1985Related words
adjective seismic

earthquake

nounA shaking of the earth:quake, seism, temblor, tremblor, tremor.Informal: shake.

Translations

地震

earth

(əːð) noun1. the third planet in order of distance from the Sun; the planet on which we live. Is Earth nearer the Sun than Mars is?; the geography of the earth.地球2. the world as opposed to heaven. heaven and earth. 尘世，人间 3. soil. Fill the plant-pot with earth.土4. dry land; the ground. the earth, sea and sky. 陆地，地面 5. a burrow or hole of an animal, especially of a fox. 洞穴6. (a wire that provides) an electrical connection with the earth. （电）接地 verb to connect to earth electrically. Is your washing-machine properly earthed?接地ˈearthen adjective (of a floor etc) made of earth. 泥土做的，陶制的 ˈearthly adjective1. of or belonging to this world; not heavenly or spiritual. this earthly life. 人间的，地球的 2. possible. This gadget has no earthly use.可能的ˈearthenware noun, adjective (of) a kind of pottery coarser than china. an earthenware dish.陶器ˈearthquake noun a shaking of the earth's surface. The village was destroyed by an earthquake.地震ˈearthworm noun (usually worm) a kind of small animal with a ringed body and no backbone, living in damp earth. 蚯蚓on earth used for emphasis. What on earth are you doing?; the stupidest man on earth. （用于加强语气）究竟 run to earth to find (something or someone) after a long search. He ran his friend to earth in the pub.经过长时间追查后找到

earthquake

→ 地震zhCN

earthquake

earthquake,

trembling or shaking movement of the earth's surface. Most earthquakes are minor tremors. Larger earthquakes usually begin with slight tremors but rapidly take the form of one or more violent shocks, and end in vibrations of gradually diminishing force called aftershocks. The subterranean point of origin of an earthquake is called its focus; the point on the surface directly above the focus is the epicenter. The magnitude and intensity of an earthquake is determined by the use of scales, e.g., the moment magnitude scale, Richter scaleRichter scale
, measure of the magnitude of seismic waves from an earthquake. Devised in 1935 by the American seismologist Charles F. Richter (1900–1985) and technically known as the local magnitude scale, it has been superseded by the moment magnitude scale, which was
..... Click the link for more information. , and the modified Mercalli scale.

Causes of Earthquakes

Most earthquakes are causally related to compressional or tensional stresses built up at the margins of the huge moving lithospheric plates that make up the earth's surface (see lithospherelithosphere
, brittle uppermost shell of the earth, broken into a number of tectonic plates. The lithosphere consists of the heavy oceanic and lighter continental crusts, and the uppermost portion of the mantle.
..... Click the link for more information. ). The immediate cause of most shallow earthquakes is the sudden release of stress along a faultfault,
in geology, fracture in the earth's crust in which the rock on one side of the fracture has measurable movement in relation to the rock on the other side. Faults on other planets and satellites of the solar system also have been recognized.
..... Click the link for more information. , or fracture in the earth's crust, resulting in movement of the opposing blocks of rock past one another. These movements cause vibrations to pass through and around the earth in wave form, just as ripples are generated when a pebble is dropped into water. An earthquake on one fault can trigger the sudden release of stress on a nearby fault and even cause a complex earthquake that propagates through several neighboring faults under the appropriate geological conditions. Volcanic eruptions, rockfalls, landslides, and explosions can also cause a quake, but most of these are of only local extent. Earthquakes have also been associated with hydraulic fracturing, or fracking, a drilling technique that injects slurry under pressure into a well, and with the disposal of fracking wastewater in old wells, most notably in N and central Oklahoma, where injection of wastewater in disposal wells has led to a significant increase in the number and strength of earthquakes since 2009. Shock waves from a powerful earthquake can trigger smaller earthquakes in a distant location hundreds of miles away if the geologic conditions are favorable.

See also plate tectonicsplate tectonics,
theory that unifies many of the features and characteristics of continental drift and seafloor spreading into a coherent model and has revolutionized geologists' understanding of continents, ocean basins, mountains, and earth history.
..... Click the link for more information. .

Seismic Waves

There are several types of earthquake waves including P, or primary, waves, which are compressional, travel fastest, and are the least destructive; and S, or secondary, waves, which are transverse, i.e., they cause the earth to vibrate perpendicularly to the direction of their motion. P and S waves are known as body waves because they propograte within the body of the earth. Surface waves consist of two main types, Love and Rayleigh waves; they move more slowly than P and S waves. Love waves cause horizontal shifting at the surface, and Rayleigh waves, the slowest moving, have a rolling motion similar to that of an ocean wave and vertically displace the earth's surface. Since the velocities of the P and S waves are affected by changes in the density and rigidity of the material through which they pass, the boundaries between the regions of the earth known as the crust, mantle, and core have been discerned by seismologists, scientists who deal with the analysis and interpretation of earthquake waves (see earthearth,
in geology and astronomy, 3rd planet of the solar system and the 5th largest, the only planet definitely known to support life. Gravitational forces have molded the earth, like all celestial bodies, into a spherical shape.
..... Click the link for more information. ). Seismographs (see seismologyseismology
, scientific study of earthquakes and related phenomena, including the propagation of waves and shocks on or within the earth by natural or artificially generated seismic signals.
..... Click the link for more information. ) are used to record seismic waves. The disappearance of S waves below depths of 1,800 mi (2,900 km) indicates that at least the outer part of the earth's core is liquid.

Damage Caused by Earthquakes

The effects of an earthquake are strongest in a broad zone surrounding the epicenter. Surface ground cracking associated with faults that reach the surface often occurs, with horizontal and vertical displacements of several yards common. Such movement does not have to occur during a major earthquake; slight periodic movements called fault creep can be accompanied by microearthquakes too small to be felt. The extent of earthquake vibration and subsequent damage to a region is partly dependent on characteristics of the ground. For example, earthquake vibrations last longer and are of greater wave amplitudes in unconsolidated surface material, such as poorly compacted fill or river deposits, and soil with a significant water content can destabilize, liquefy, and even flow, causing structures and infrastructure to sink or be displaced. Bedrock areas receive fewer effects. The worst damage occurs in densely populated urban areas where structures are not built to withstand intense shaking. There, surface waves can produce destructive vibrations in buildings and break water and gas lines, starting uncontrollable fires.

Damage and loss of life sustained during an earthquake result from falling structures and flying glass and objects. Flexible structures built on bedrock are generally more resistant to earthquake damage than rigid structures built on loose soil. In certain areas, an earthquake can trigger mudslides, which slip down mountain slopes and can bury habitations below. A submarine earthquake can cause a tsunamitsunami
, series of catastrophic ocean waves generated by submarine movements, which may be caused by earthquakes, volcanic eruptions, landslides beneath the ocean, or an asteroid striking the earth. Tsunamis are also called seismic sea waves or, popularly, tidal waves.
..... Click the link for more information. , a series of damaging waves that ripple outward from the earthquake epicenter and inundate coastal cities.

Earthquake Warning Systems

Modern earthquake warning systems have been developed by several nations, and may be deployed nationwide or regionally. They depend on the detection of P waves by seismometers, and the transmission of that detection to affected populations by various means. Because P waves travel faster and are much less destructive than the later-arriving seismic waves an earthquake also produces, their detection can provide early warning, of a few seconds to several tens of seconds, of the arrival of the destructive shaking associated with an earthquake. If an earthquake's epicenter is close to a given location, however, the several types of waves will arrive closer together and little or no early warning will be possible.

Warning can be provided through several means including sirens and public loudspeakers, radio and television broadcasts, text messaging, and smartphone apps including dedicated earthquake-alert apps. More sophisticated systems can give some indication of the duration and severity of the earthquake. Early warning, even though measured in seconds, may permit people to take protective measures to prevent or limit injury, allow authorities to halt trains and subways and stop traffic from entering bridges and tunnels, and alert emergency responders to take measures to prevent their vehicles from becoming inaccessible or damaged.

Major Earthquakes

On average about 1,000 earthquakes with intensities of 5.0 or greater are recorded each year. Great earthquakes (magnitude 8.0 or higher) occur once a year, major earthquakes (magnitude 7.0–7.9) occur 18 times a year, strong earthquakes (magnitude 6.0–6.9) 10 times a month, and moderate earthquakes (magnitude 5.0–5.9) more than twice a day. Because most of these occur under the ocean or in underpopulated areas, they pass unnoticed by all but seismologists. Moderate to strong earthquakes can cause more significant destruction if they occur closer to the earth's surface. Notable earthquakes have occurred at Lisbon, Portugal (1755); New Madrid, Mo. (1811 and 1812); Charleston, S.C. (1886); Assam, India (1897 and 1950); San Francisco (1906); Messina, Italy (1908); Gansu, China (1920); Tokyo, Japan (1923); Chile (1960); Iran (1962); S Alaska (1964); Managua, Nicaragua (1972); Guatemala (1976); Hebei, China (1976); Mexico (1985); Armenia (1988); Luzon, Philippines (1990); N Japan (1993); Kobe, Japan (1995); Izmit, Turkey (1999); central Taiwan (1999); Oaxaca state, Mexico (1999); Bam, Iran (2003); NW Sumatra, Indonesia (2004); Sichuan, China (2008); S Haiti (2010); Chile (2010); South Island, New Zealand (2010, 2011); NE Japan (2011); and W Sulawesi, Indonesia (2018). The Lisbon, Chilean, Alaskan, Sumatran, NE Japan, and Sulawesi earthquakes were accompanied by significant tsunamistsunami
, series of catastrophic ocean waves generated by submarine movements, which may be caused by earthquakes, volcanic eruptions, landslides beneath the ocean, or an asteroid striking the earth. Tsunamis are also called seismic sea waves or, popularly, tidal waves.
..... Click the link for more information. .

Twelve of the twenty largest earthquakes in the United States have occurred in Alaska. Most of the largest in the continental United States have occurred in California or elsewhere along the Pacific Coast, but the three New Madrid earthquakes (1811–12) also were among the largest continental events, as was the Charleston, S.C., earthquake (1886). On Good Friday 1964, one of the most severe North American earthquakes ever recorded struck near Anchorage, Alaska, measuring 8.4 to 8.6 in magnitude. Besides elevating some 70,000 sq mi (181,300 sq km) of land and devastating several cities, it generated a tsunami that caused damage as far south as California. Other recent earthquakes that have affected the United States include the Feb., 1971, movement of the San Fernando fault near Los Angeles. It rocked the area for 10 sec, thrust parts of mountains 8 ft (2.4 m) upward, killed 64 persons, and caused damage amounting to $500 million. In 1989, the Loma Prieta earthquake above Santa Cruz shook for 15 seconds at an magnitude of 7.1, killed 67 people, and toppled buildings and bridges. In Jan., 1994, an earthquake measuring 6.6 with its epicenter in N Los Angeles caused major damage to the city's infrastructure and left thousands homeless.

Bibliography

See C. H. Scholz, The Mechanics of Earthquakes and Faulting (1991); C. Lomnitz, Fundamentals of Earthquake Prediction (1994); D. S. Brumbaugh, Earthquakes: Science and Society (1998); B. A. Bolt, Earthquakes (4th ed. 1999). See also bibliography under seismologyseismology
, scientific study of earthquakes and related phenomena, including the propagation of waves and shocks on or within the earth by natural or artificially generated seismic signals.
..... Click the link for more information. .

What does it mean when you dream about an earthquake?

Dreams about natural disasters often occur during life crises—during major “shake-ups.” The earth represents the material basis of life, so an earthquake can be an especially appropriate symbol of financial upheaval. Dreams about earthquakes may also occur during life-threatening illnesses or in the recovery period following life-threatening accidents.

earthquake

[′ərth‚kwāk] (geophysics) A sudden movement of the earth caused by the abrupt release of accumulated strain along a fault in the interior. The released energy passes through the earth as seismic waves (low-frequency sound waves), which cause the shaking.

earthquake

a sudden release of energy in the earth's crust or upper mantle, usually caused by movement along a fault plane or by volcanic activity and resulting in the generation of seismic waves which can be destructive

earthquake

(IBM) The ultimate real-world shock test for computerhardware. Hackish sources at IBM deny the rumor that theSan Francisco Bay Area quake of 1989 was initiated by thecompany to test quality-assurance procedures at its Californiaplants.

Earthquake

(dreams)Unlike some of the other dreams about natural disasters, earthquakes usually symbolize parts of the dreamer’s physical reality rather than his emotional life. The earthquake in the dream may be representing financial difficulties, health issues, or any number of other problems that could occur in daily life. An experience that is “shaking” you up, and changing your daily life, could be creeping into your dream state and showing up as an earthquake.

earthquake

earth·quake

earthquake

earth•quake

earth·quake

earthquake

earthquake

earthquake

earth

earthquake

earthquake

earthquake,

Causes of Earthquakes

Seismic Waves

Damage Caused by Earthquakes

Earthquake Warning Systems

Major Earthquakes

Bibliography

What does it mean when you dream about an earthquake?

earthquake

earthquake

earthquake

Earthquake

Earthquake

earthquake

Synonyms for earthquake

noun earth tremor

Synonyms

Synonyms for earthquake

noun a shaking of the earth

Synonyms

Synonyms for earthquake

noun shaking and vibration at the surface of the earth resulting from underground movement along a fault plane of from volcanic activity

Synonyms

Related Words

noun a disturbance that is extremely disruptive

Related Words