Sudden movement of the Earth's crust
An
earthquake
– also called a
quake
,
tremor
, or
temblor
– is the shaking of the
Earth
's surface resulting from a sudden release of energy in the
lithosphere
that creates
seismic waves
. Earthquakes can range in
intensity
, from those so weak they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The
seismic activity
of an area is the frequency, type, and size of earthquakes experienced over a particular time. The
seismicity
at a particular location in the Earth is the average rate of seismic energy release per unit volume.
In its most general sense, the word
earthquake
is used to describe any seismic event that generates seismic waves. Earthquakes can occur naturally or be induced by human activities, such as
mining
,
fracking
, and
nuclear tests
. The initial point of rupture is called the
hypocenter
or focus, while the ground level directly above it is the
epicenter
. Earthquakes are primarily caused by geological
faults
, but also by
volcanic activity
, landslides, and other seismic events. The frequency, type, and size of earthquakes in an area define its seismic activity, reflecting the average rate of seismic energy release.
Significant historical earthquakes include the
1556 Shaanxi earthquake
in China, with over 830,000 fatalities, and the
1960 Valdivia earthquake
in Chile, the largest ever recorded at 9.5 magnitude. Earthquakes result in various effects, such as ground shaking and
soil liquefaction
, leading to significant damage and loss of life. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a
tsunami
. Earthquakes can trigger
landslides
. Earthquakes' occurrence is influenced by
tectonic
movements along faults, including normal, reverse (thrust), and strike-slip faults, with energy release and rupture dynamics governed by the
elastic-rebound theory
.
Efforts to manage earthquake risks involve prediction, forecasting, and preparedness, including
seismic retrofitting
and
earthquake engineering
to design structures that withstand shaking. The cultural impact of earthquakes spans myths, religious beliefs, and modern media, reflecting their profound influence on human societies. Similar seismic phenomena, known as
marsquakes
and
moonquakes
, have been observed on other celestial bodies, indicating the universality of such events beyond Earth.
Terminology
An earthquake is the shaking of the surface of
Earth
resulting from a sudden release of energy in the
lithosphere
that creates
seismic waves
. Earthquakes may also be referred to as
quakes
,
tremors
, or
temblors
. The word
tremor
is also used for
non-earthquake seismic rumbling
.
In its most general sense, an
earthquake
is any seismic event?whether natural or caused by humans?that generates seismic waves. Earthquakes are caused mostly by the rupture of geological
faults
but also by other events such as volcanic activity, landslides, mine blasts,
fracking
and
nuclear tests
. An earthquake's point of initial rupture is called its
hypocenter
or focus. The
epicenter
is the point at ground level directly above the hypocenter.
The
seismic activity
of an area is the frequency, type, and size of earthquakes experienced over a particular time. The
seismicity
at a particular location in the Earth is the average rate of seismic energy release per unit volume.
Major examples
One of the most devastating earthquakes in recorded history was the
1556 Shaanxi earthquake
, which occurred on 23 January 1556 in
Shaanxi
, China. More than 830,000 people died.
[2]
Most houses in the area were
yaodongs
?dwellings carved out of
loess
hillsides?and many victims were killed when these structures collapsed. The
1976 Tangshan earthquake
, which killed between 240,000 and 655,000 people, was the deadliest of the 20th century.
[3]
The
1960 Chilean earthquake
is the largest earthquake that has been measured on a seismograph, reaching 9.5 magnitude on 22 May 1960.
[4]
[5]
Its epicenter was near Canete, Chile. The energy released was approximately twice that of the next most powerful earthquake, the
Good Friday earthquake
(27 March 1964), which was centered in
Prince William Sound
, Alaska.
[6]
[7]
The ten largest recorded earthquakes have all been
megathrust earthquakes
; however, of these ten, only the
2004 Indian Ocean earthquake
is simultaneously one of the deadliest earthquakes in history.
Earthquakes that caused the greatest loss of life, while powerful, were deadly because of their proximity to either heavily populated areas or the ocean, where earthquakes often create
tsunamis
that can devastate communities thousands of kilometers away. Regions most at risk for great loss of life include those where earthquakes are relatively rare but powerful, and poor regions with lax, unenforced, or nonexistent seismic building codes.
Occurrence
Tectonic
earthquakes occur anywhere on the earth where there is sufficient stored elastic strain energy to drive fracture propagation along a
fault plane
. The sides of a fault move past each other smoothly and
aseismically
only if there are no irregularities or
asperities
along the fault surface that increases the frictional resistance. Most fault surfaces do have such asperities, which leads to a form of
stick-slip behavior
. Once the fault has locked, continued relative motion between the plates leads to increasing stress and, therefore, stored strain energy in the volume around the fault surface. This continues until the stress has risen sufficiently to break through the asperity, suddenly allowing sliding over the locked portion of the fault, releasing the
stored energy
.
[8]
This energy is released as a combination of radiated elastic
strain
seismic waves
,
[9]
frictional heating of the fault surface, and cracking of the rock, thus causing an earthquake. This process of gradual build-up of strain and stress punctuated by occasional sudden earthquake failure is referred to as the
elastic-rebound theory
. It is estimated that only 10 percent or less of an earthquake's total energy is radiated as seismic energy. Most of the earthquake's energy is used to power the earthquake
fracture
growth or is converted into heat generated by friction. Therefore, earthquakes lower the Earth's available
elastic potential energy
and raise its temperature, though these changes are negligible compared to the conductive and convective flow of heat out from the
Earth's deep interior.
[10]
Fault types
There are three main types of fault, all of which may cause an
interplate earthquake
: normal, reverse (thrust), and strike-slip. Normal and reverse faulting are examples of dip-slip, where the displacement along the fault is in the direction of
dip
and where movement on them involves a vertical component. Many earthquakes are caused by movement on faults that have components of both dip-slip and strike-slip; this is known as oblique slip. The topmost, brittle part of the Earth's crust, and the cool slabs of the tectonic plates that are descending into the hot mantle, are the only parts of our planet that can store elastic energy and release it in fault ruptures. Rocks hotter than about 300 °C (572 °F) flow in response to stress; they do not rupture in earthquakes.
[11]
[12]
The maximum observed lengths of ruptures and mapped faults (which may break in a single rupture) are approximately 1,000 km (620 mi). Examples are the earthquakes in
Alaska (1957)
,
Chile (1960)
, and
Sumatra (2004)
, all in subduction zones. The longest earthquake ruptures on strike-slip faults, like the
San Andreas Fault
(
1857
,
1906
), the
North Anatolian Fault
in Turkey (
1939
), and the
Denali Fault
in Alaska (
2002
), are about half to one third as long as the lengths along subducting plate margins, and those along normal faults are even shorter.
Normal faults
Normal faults occur mainly in areas where the crust is being
extended
such as a
divergent boundary
. Earthquakes associated with normal faults are generally less than magnitude 7. Maximum magnitudes along many normal faults are even more limited because many of them are located along spreading centers, as in Iceland, where the thickness of the brittle layer is only about six kilometres (3.7 mi).
[13]
[14]
Reverse faults
Reverse faults occur in areas where the crust is being
shortened
such as at a
convergent boundary
. Reverse faults, particularly those along convergent boundaries, are associated with the most powerful earthquakes (called
megathrust earthquakes
) including almost all of those of magnitude 8 or more. Megathrust earthquakes are responsible for about 90% of the total seismic moment released worldwide.
[15]
Strike-slip faults
Strike-slip faults
are steep structures where the two sides of the fault slip horizontally past each other; transform boundaries are a particular type of strike-slip fault. Strike-slip faults, particularly continental
transforms
, can produce major earthquakes up to about magnitude 8. Strike-slip faults tend to be oriented near vertically, resulting in an approximate width of 10 km (6.2 mi) within the brittle crust.
[16]
Thus, earthquakes with magnitudes much larger than 8 are not possible.
In addition, there exists a hierarchy of stress levels in the three fault types. Thrust faults are generated by the highest, strike-slip by intermediate, and normal faults by the lowest stress levels.
[17]
This can easily be understood by considering the direction of the greatest principal stress, the direction of the force that "pushes" the rock mass during the faulting. In the case of normal faults, the rock mass is pushed down in a vertical direction, thus the pushing force (
greatest
principal stress) equals the weight of the rock mass itself. In the case of thrusting, the rock mass "escapes" in the direction of the least principal stress, namely upward, lifting the rock mass, and thus, the overburden equals the
least
principal stress. Strike-slip faulting is intermediate between the other two types described above. This difference in stress regime in the three faulting environments can contribute to differences in stress drop during faulting, which contributes to differences in the radiated energy, regardless of fault dimensions.
Energy released
For every unit increase in magnitude, there is a roughly thirty-fold increase in the energy released. For instance, an earthquake of magnitude 6.0 releases approximately 32 times more energy than a 5.0 magnitude earthquake and a 7.0 magnitude earthquake releases 1,000 times more energy than a 5.0 magnitude earthquake. An 8.6-magnitude earthquake releases the same amount of energy as 10,000 atomic bombs of the size used in
World War II
.
[18]
This is so because the energy released in an earthquake, and thus its magnitude, is proportional to the area of the fault that ruptures
[19]
and the stress drop. Therefore, the longer the length and the wider the width of the faulted area, the larger the resulting magnitude. The most important parameter controlling the maximum earthquake magnitude on a fault, however, is not the maximum available length, but the available width because the latter varies by a factor of 20. Along converging plate margins, the dip angle of the rupture plane is very shallow, typically about 10 degrees.
[20]
Thus, the width of the plane within the top brittle crust of the Earth can reach 50?100 km (31?62 mi) (such as in
Japan, 2011
, or in
Alaska, 1964
), making the most powerful earthquakes possible.
Focus
The majority of tectonic earthquakes originate in the Ring of Fire at depths not exceeding tens of kilometers. Earthquakes occurring at a depth of less than 70 km (43 mi) are classified as "shallow-focus" earthquakes, while those with a focal depth between 70 and 300 km (43 and 186 mi) are commonly termed "mid-focus" or "intermediate-depth" earthquakes. In
subduction
zones, where older and colder
oceanic crust
descends beneath another tectonic plate,
deep-focus earthquakes
may occur at much greater depths (ranging from 300 to 700 km (190 to 430 mi)).
[21]
These seismically active areas of subduction are known as
Wadati?Benioff zones
. Deep-focus earthquakes occur at a depth where the subducted
lithosphere
should no longer be brittle, due to the high temperature and pressure. A possible mechanism for the generation of deep-focus earthquakes is faulting caused by
olivine
undergoing a
phase transition
into a
spinel
structure.
[22]
Volcanic activity
Earthquakes often occur in volcanic regions and are caused there, both by
tectonic
faults and the movement of
magma
in
volcanoes
. Such earthquakes can serve as an early warning of volcanic eruptions, as during the
1980 eruption of Mount St. Helens
.
[23]
Earthquake swarms can serve as markers for the location of the flowing magma throughout the volcanoes. These swarms can be recorded by
seismometers
and
tiltmeters
(a device that measures ground slope) and used as sensors to predict imminent or upcoming eruptions.
[24]
Rupture dynamics
A tectonic earthquake begins as an area of initial slip on the fault surface that forms the focus. Once the rupture has been initiated, it begins to propagate away from the focus, spreading out along the fault surface. Lateral propagation will continue until either the rupture reaches a barrier, such as the end of a fault segment, or a region on the fault where there is insufficient stress to allow continued rupture. For larger earthquakes, the depth extent of rupture will be constrained downwards by the
brittle-ductile transition zone
and upwards by the ground surface. The mechanics of this process are poorly understood because it is difficult either to recreate such rapid movements in a laboratory or to record seismic waves close to a nucleation zone due to strong ground motion.
[25]
In most cases, the rupture speed approaches, but does not exceed, the
shear wave
(S-wave) velocity of the surrounding rock. There are a few exceptions to this:
Supershear earthquakes
Supershear earthquake
ruptures are known to have propagated at speeds greater than the S-wave velocity. These have so far all been observed during large strike-slip events. The unusually wide zone of damage caused by the
2001 Kunlun earthquake
has been attributed to the effects of the
sonic boom
developed in such earthquakes.
Slow earthquakes
Slow earthquake
ruptures travel at unusually low velocities. A particularly dangerous form of slow earthquake is the
tsunami earthquake
, observed where the relatively low felt intensities, caused by the slow propagation speed of some great earthquakes, fail to alert the population of the neighboring coast, as in the
1896 Sanriku earthquake
.
[25]
Co-seismic overpressuring and effect of pore pressure
During an earthquake, high temperatures can develop at the fault plane, increasing pore pressure and consequently vaporization of the groundwater already contained within the rock.
[27]
[28]
[29]
In the coseismic phase, such an increase can significantly affect slip evolution and speed, in the post-seismic phase it can control the
Aftershock
sequence because, after the main event, pore pressure increase slowly propagates into the surrounding fracture network.
[30]
[29]
From the point of view of the
Mohr-Coulomb strength theory
, an increase in fluid pressure reduces the normal stress acting on the fault plane that holds it in place, and fluids can exert a lubricating effect. As thermal overpressurization may provide positive feedback between slip and strength fall at the fault plane, a common opinion is that it may enhance the faulting process instability. After the mainshock, the pressure gradient between the fault plane and the neighboring rock causes a fluid flow that increases pore pressure in the surrounding fracture networks; such an increase may trigger new faulting processes by reactivating adjacent faults, giving rise to aftershocks.
[30]
[29]
Analogously, artificial pore pressure increase, by fluid injection in Earth's crust, may
induce seismicity
.
Tidal forces
Tides
may trigger some
seismicity
.
Clusters
Most earthquakes form part of a sequence, related to each other in terms of location and time.
[31]
Most earthquake clusters consist of small tremors that cause little to no damage, but there is a theory that earthquakes can recur in a regular pattern.
[32]
Earthquake clustering has been observed, for example, in Parkfield, California where a long-term research study is being conducted around the
Parkfield earthquake
cluster.
[33]
Aftershocks
An aftershock is an earthquake that occurs after a previous earthquake, the mainshock. Rapid changes of stress between rocks, and the stress from the original earthquake are the main causes of these aftershocks,
[34]
along with the crust around the ruptured
fault plane
as it adjusts to the effects of the mainshock.
[31]
An aftershock is in the same region as the main shock but always of a smaller magnitude, however, they can still be powerful enough to cause even more damage to buildings that were already previously damaged from the mainshock.
[34]
If an aftershock is larger than the mainshock, the aftershock is redesignated as the mainshock and the original main shock is redesignated as a
foreshock
. Aftershocks are formed as the crust around the displaced
fault plane
adjusts to the effects of the mainshock.
[31]
Swarms
Earthquake swarms are sequences of earthquakes striking in a specific area within a short period. They are different from earthquakes followed by a series of
aftershocks
by the fact that no single earthquake in the sequence is the main shock, so none has a notably higher magnitude than another. An example of an earthquake swarm is the 2004 activity at
Yellowstone National Park
.
[35]
In August 2012, a swarm of earthquakes shook
Southern California
's
Imperial Valley
, showing the most recorded activity in the area since the 1970s.
[36]
Sometimes a series of earthquakes occur in what has been called an
earthquake storm
, where the earthquakes strike a fault in clusters, each triggered by the shaking or
stress redistribution
of the previous earthquakes. Similar to
aftershocks
but on adjacent segments of fault, these storms occur over the course of years, with some of the later earthquakes as damaging as the early ones. Such a pattern was observed in the sequence of about a dozen earthquakes that struck the
North Anatolian Fault
in Turkey in the 20th century and has been inferred for older anomalous clusters of large earthquakes in the Middle East.
[37]
[38]
Frequency
It is estimated that around 500,000 earthquakes occur each year, detectable with current instrumentation. About 100,000 of these can be felt.
[4]
[5]
Minor earthquakes occur very frequently around the world in places like California and Alaska in the U.S., as well as in El Salvador, Mexico, Guatemala, Chile, Peru, Indonesia, the Philippines, Iran, Pakistan, the
Azores
in Portugal, Turkey, New Zealand, Greece, Italy, India, Nepal, and Japan.
[40]
Larger earthquakes occur less frequently, the relationship being
exponential
; for example, roughly ten times as many earthquakes larger than magnitude 4 occur than earthquakes larger than magnitude 5.
[41]
In the (low seismicity) United Kingdom, for example, it has been calculated that the average recurrences are:
an earthquake of 3.7?4.6 every year, an earthquake of 4.7?5.5 every 10 years, and an earthquake of 5.6 or larger every 100 years.
[42]
This is an example of the
Gutenberg?Richter law
.
The number of seismic stations has increased from about 350 in 1931 to many thousands today. As a result, many more earthquakes are reported than in the past, but this is because of the vast improvement in instrumentation, rather than an increase in the number of earthquakes. The
United States Geological Survey
(USGS) estimates that, since 1900, there have been an average of 18 major earthquakes (magnitude 7.0?7.9) and one great earthquake (magnitude 8.0 or greater) per year, and that this average has been relatively stable.
[43]
In recent years, the number of major earthquakes per year has decreased, though this is probably a statistical fluctuation rather than a systematic trend.
[44]
More detailed statistics on the size and frequency of earthquakes is available from the United States Geological Survey.
[45]
A recent increase in the number of major earthquakes has been noted, which could be explained by a cyclical pattern of periods of intense tectonic activity, interspersed with longer periods of low intensity. However, accurate recordings of earthquakes only began in the early 1900s, so it is too early to categorically state that this is the case.
[46]
Most of the world's earthquakes (90%, and 81% of the largest) take place in the 40,000-kilometre-long (25,000 mi), horseshoe-shaped zone called the circum-Pacific seismic belt, known as the
Pacific Ring of Fire
, which for the most part bounds the
Pacific Plate
.
[47]
[48]
Massive earthquakes tend to occur along other plate boundaries too, such as along the
Himalayan Mountains
.
[49]
With the rapid growth of
mega-cities
such as Mexico City, Tokyo, and Tehran in areas of high
seismic risk
, some seismologists are warning that a single earthquake may claim the lives of up to three million people.
[50]
Induced seismicity
While most earthquakes are caused by the movement of the Earth's
tectonic plates
, human activity can also produce earthquakes. Activities both above ground and below may change the stresses and strains on the crust, including building reservoirs, extracting resources such as coal or oil, and injecting fluids underground for waste disposal or
fracking
.
[51]
Most of these earthquakes have small magnitudes. The 5.7 magnitude
2011 Oklahoma earthquake
is thought to have been caused by disposing wastewater from oil production into
injection wells
,
[52]
and studies point to the state's oil industry as the cause of other earthquakes in the past century.
[53]
A
Columbia University
paper suggested that the 8.0 magnitude
2008 Sichuan earthquake
was induced by loading from the
Zipingpu Dam
,
[54]
though the link has not been conclusively proved.
[55]
Measurement and location
The instrumental scales used to describe the size of an earthquake began with the
Richter magnitude scale
in the 1930s. It is a relatively simple measurement of an event's amplitude, and its use has become minimal in the 21st century.
Seismic waves
travel through the
Earth's interior
and can be recorded by
seismometers
at great distances. The
surface wave magnitude
was developed in the 1950s as a means to measure remote earthquakes and to improve the accuracy for larger events. The
moment magnitude scale
not only measures the amplitude of the shock but also takes into account the
seismic moment
(total rupture area, average slip of the fault, and rigidity of the rock). The
Japan Meteorological Agency seismic intensity scale
, the
Medvedev?Sponheuer?Karnik scale
, and the
Mercalli intensity scale
are based on the observed effects and are related to the intensity of shaking.
Intensity and magnitude
The shaking of the earth is a common phenomenon that has been experienced by humans from the earliest of times. Before the development of strong-motion accelerometers, the intensity of a seismic event was estimated based on the observed effects. Magnitude and intensity are not directly related and calculated using different methods. The magnitude of an earthquake is a single value that describes the size of the earthquake at its source. Intensity is the measure of shaking at different locations around the earthquake. Intensity values vary from place to place, depending on the distance from the earthquake and the underlying rock or soil makeup.
[56]
The
first scale for measuring earthquake magnitudes
was developed by
Charles Francis Richter
in 1935. Subsequent scales (
seismic magnitude scales
) have retained a key feature, where each unit represents a ten-fold difference in the amplitude of the ground shaking and a 32-fold difference in energy. Subsequent scales are also adjusted to have approximately the same numeric value within the limits of the scale.
[57]
Although the mass media commonly reports earthquake magnitudes as "Richter magnitude" or "Richter scale", standard practice by most seismological authorities is to express an earthquake's strength on the
moment magnitude
scale, which is based on the actual energy released by an earthquake, the static seismic moment.
[58]
[59]
Seismic waves
Every earthquake produces different types of seismic waves, which travel through rock with different velocities:
Speed of seismic waves
Propagation velocity
of the seismic waves through solid rock ranges from approx. 3 km/s (1.9 mi/s) up to 13 km/s (8.1 mi/s), depending on the
density
and
elasticity
of the medium. In the Earth's interior, the shock- or P-waves travel much faster than the S-waves (approx. relation 1.7:1). The differences in travel time from the
epicenter
to the observatory are a measure of the distance and can be used to image both sources of earthquakes and structures within the Earth. Also, the depth of the
hypocenter
can be computed roughly.
P-wave speed
- Upper crust soils and unconsolidated sediments: 2?3 km (1.2?1.9 mi) per second
- Upper crust solid rock: 3?6 km (1.9?3.7 mi) per second
- Lower crust: 6?7 km (3.7?4.3 mi) per second
- Deep mantle: 13 km (8.1 mi) per second.
S-waves speed
- Light sediments: 2?3 km (1.2?1.9 mi) per second
- Earths crust: 4?5 km (2.5?3.1 mi) per second
- Deep mantle: 7 km (4.3 mi) per second
Seismic wave arrival
As a consequence, the first waves of a distant earthquake arrive at an observatory via the Earth's mantle.
On average, the kilometer distance to the earthquake is the number of seconds between the P- and S-wave times 8.
[60]
Slight deviations are caused by inhomogeneities of subsurface structure. By such analysis of seismograms, the Earth's core was located in 1913 by
Beno Gutenberg
.
S-waves and later arriving surface waves do most of the damage compared to P-waves. P-waves squeeze and expand the material in the same direction they are traveling, whereas S-waves shake the ground up and down and back and forth.
[61]
Location and reporting
Earthquakes are not only categorized by their magnitude but also by the place where they occur. The world is divided into 754
Flinn?Engdahl regions
(F-E regions), which are based on political and geographical boundaries as well as seismic activity. More active zones are divided into smaller F-E regions whereas less active zones belong to larger F-E regions.
Standard reporting of earthquakes includes its
magnitude
, date and time of occurrence,
geographic coordinates
of its
epicenter
, depth of the epicenter, geographical region, distances to population centers, location uncertainty, several parameters that are included in USGS earthquake reports (number of stations reporting, number of observations, etc.), and a unique event ID.
[62]
Although relatively slow seismic waves have traditionally been used to detect earthquakes, scientists realized in 2016 that gravitational measurement could provide instantaneous detection of earthquakes, and confirmed this by analyzing gravitational records associated with the
2011 Tohoku-Oki
("Fukushima") earthquake.
[63]
[64]
Effects
The effects of earthquakes include, but are not limited to, the following:
Shaking and ground rupture
Shaking and
ground rupture
are the main effects created by earthquakes, principally resulting in more or less severe damage to buildings and other rigid structures. The severity of the local effects depends on the complex combination of the earthquake
magnitude
, the distance from the
epicenter
, and the local geological and geomorphological conditions, which may amplify or reduce
wave propagation
.
[65]
The ground-shaking is measured by
ground acceleration
.
Specific local geological, geomorphological, and geostructural features can induce high levels of shaking on the ground surface even from low-intensity earthquakes. This effect is called site or local amplification. It is principally due to the transfer of the
seismic
motion from hard deep soils to soft superficial soils and the effects of seismic energy focalization owing to the typical geometrical setting of such deposits.
Ground rupture is a visible breaking and displacement of the Earth's surface along the trace of the fault, which may be of the order of several meters in the case of major earthquakes. Ground rupture is a major risk for large engineering structures such as
dams
, bridges, and
nuclear power stations
and requires careful mapping of existing faults to identify any that are likely to break the ground surface within the life of the structure.
[66]
Soil liquefaction
Soil liquefaction occurs when, because of the shaking, water-saturated
granular
material (such as sand) temporarily loses its strength and transforms from a solid to a liquid. Soil liquefaction may cause rigid structures, like buildings and bridges, to tilt or sink into the liquefied deposits. For example, in the
1964 Alaska earthquake
, soil liquefaction caused many buildings to sink into the ground, eventually collapsing upon themselves.
[67]
Human impacts
Physical damage from an earthquake will vary depending on the intensity of shaking in a given area and the type of population. Underserved and developing communities frequently experience more severe impacts (and longer lasting) from a seismic event compared to well-developed communities.
[68]
Impacts may include:
- Injuries and loss of life
- Damage to critical infrastructure (short and long-term)
- Roads, bridges, and public transportation networks
- Water, power, sewer and gas interruption
- Communication systems
- Loss of critical community services including hospitals, police, and fire
- General
property damage
- Collapse or destabilization (potentially leading to future collapse) of buildings
With these impacts and others, the aftermath may bring disease, a lack of basic necessities, mental consequences such as panic attacks and depression to survivors,
[69]
and higher insurance premiums. Recovery times will vary based on the level of damage and the socioeconomic status of the impacted community.
Landslides
Earthquakes can produce slope instability leading to landslides, a major geological hazard. Landslide danger may persist while emergency personnel is attempting rescue work.
[70]
Fires
Earthquakes can cause fires by damaging
electrical power
or gas lines. In the event of water mains rupturing and a loss of pressure, it may also become difficult to stop the spread of a fire once it has started. For example, more deaths in the
1906 San Francisco earthquake
were caused by fire than by the earthquake itself.
[71]
Tsunami
Tsunamis are long-wavelength, long-period sea waves produced by the sudden or abrupt movement of large volumes of water?including when an earthquake
occurs at sea
. In the open ocean, the distance between wave crests can surpass 100 kilometres (62 mi), and the wave periods can vary from five minutes to one hour. Such tsunamis travel 600?800 kilometers per hour (373?497 miles per hour), depending on water depth. Large waves produced by an earthquake or a submarine landslide can overrun nearby coastal areas in a matter of minutes. Tsunamis can also travel thousands of kilometers across open ocean and wreak destruction on far shores hours after the earthquake that generated them.
[72]
Ordinarily, subduction earthquakes under magnitude 7.5 do not cause tsunamis, although some instances of this have been recorded. Most destructive tsunamis are caused by earthquakes of magnitude 7.5 or more.
[72]
Floods
Further information:
Flood
Floods may be secondary effects of earthquakes if dams are damaged. Earthquakes may cause landslips to dam rivers, which collapse and cause floods.
[73]
The terrain below the
Sarez Lake
in Tajikistan is in danger of catastrophic flooding if the
landslide dam
formed by the earthquake, known as the
Usoi Dam
, were to fail during a future earthquake. Impact projections suggest the flood could affect roughly five million people.
[74]
Management
Prediction
Earthquake prediction
is a branch of the science of
seismology
concerned with the specification of the time, location, and
magnitude
of future earthquakes within stated limits.
[75]
Many methods have been developed for predicting the time and place in which earthquakes will occur. Despite considerable research efforts by
seismologists
, scientifically reproducible predictions cannot yet be made to a specific day or month.
[76]
Forecasting
While
forecasting
is usually considered to be a type of
prediction
,
earthquake forecasting
is often differentiated from
earthquake prediction
. Earthquake forecasting is concerned with the probabilistic assessment of general earthquake hazards, including the frequency and magnitude of damaging earthquakes in a given area over years or decades.
[77]
For well-understood faults the probability that a segment may rupture during the next few decades can be estimated.
[78]
[79]
Earthquake warning systems
have been developed that can provide regional notification of an earthquake in progress, but before the ground surface has begun to move, potentially allowing people within the system's range to seek shelter before the earthquake's impact is felt.
Preparedness
The objective of
earthquake engineering
is to foresee the impact of earthquakes on buildings, bridges, tunnels, roadways, and other structures, and to design such structures to minimize the risk of damage. Existing structures can be modified by
seismic retrofitting
to improve their resistance to earthquakes.
Earthquake insurance
can provide building owners with financial protection against losses resulting from earthquakes.
Emergency management
strategies can be employed by a government or organization to mitigate risks and prepare for consequences.
Artificial intelligence
may help to assess buildings and plan precautionary operations. The Igor
expert system
is part of a mobile laboratory that supports the procedures leading to the seismic assessment of masonry buildings and the planning of retrofitting operations on them. It has been applied to assess buildings in
Lisbon
,
Rhodes
, and
Naples
.
[80]
Individuals can also take preparedness steps like securing
water heaters
and heavy items that could injure someone, locating shutoffs for utilities, and being educated about what to do when the shaking starts. For areas near large bodies of water, earthquake preparedness encompasses the possibility of a tsunami caused by a large earthquake.
In culture
Historical views
From the lifetime of the Greek philosopher
Anaxagoras
in the 5th century BCE to the 14th century CE, earthquakes were usually attributed to "air (vapors) in the cavities of the Earth."
[81]
Thales
of Miletus (625?547 BCE) was the only documented person who believed that earthquakes were caused by tension between the earth and water.
[81]
Other theories existed, including the Greek philosopher Anaxamines' (585?526 BCE) beliefs that short incline episodes of dryness and wetness caused seismic activity. The Greek philosopher Democritus (460?371 BCE) blamed water in general for earthquakes.
[81]
Pliny the Elder
called earthquakes "underground thunderstorms".
[81]
Mythology and religion
In
Norse mythology
, earthquakes were explained as the violent struggle of the god
Loki
. When Loki,
god
of mischief and strife, murdered
Baldr
, god of beauty and light, he was punished by being bound in a cave with a poisonous serpent placed above his head dripping venom. Loki's wife
Sigyn
stood by him with a bowl to catch the poison, but whenever she had to empty the bowl the poison dripped on Loki's face, forcing him to jerk his head away and thrash against his bonds, which caused the earth to tremble.
[82]
In
Greek mythology
,
Poseidon
was the cause and god of earthquakes. When he was in a bad mood, he struck the ground with a
trident
, causing earthquakes and other calamities. He also used earthquakes to punish and inflict fear upon people as revenge.
[83]
In
Japanese mythology
,
Namazu
(?) is a giant
catfish
who causes earthquakes. Namazu lives in the mud beneath the earth and is guarded by the god
Kashima
who restrains the fish with a stone. When Kashima lets his guard fall, Namazu thrashes about, causing violent earthquakes.
[84]
In popular culture
In modern popular culture, the portrayal of earthquakes is shaped by the memory of great cities laid waste, such as
Kobe in 1995
or
San Francisco in 1906
.
[85]
Fictional earthquakes tend to strike suddenly and without warning.
[85]
For this reason, stories about earthquakes generally begin with the disaster and focus on its immediate aftermath, as in
Short Walk to Daylight
(1972),
The Ragged Edge
(1968) or
Aftershock: Earthquake in New York
(1999).
[85]
A notable example is Heinrich von Kleist's classic novella,
The Earthquake in Chile
, which describes the destruction of Santiago in 1647.
Haruki Murakami
's short fiction collection
After the Quake
depicts the consequences of the Kobe earthquake of 1995.
The most popular single earthquake in fiction is the hypothetical "Big One" expected of California's
San Andreas Fault
someday, as depicted in the novels
Richter 10
(1996),
Goodbye California
(1977),
2012
(2009), and
San Andreas
(2015), among other works.
[85]
Jacob M. Appel's widely anthologized short story,
A Comparative Seismology
, features a con artist who convinces an elderly woman that an apocalyptic earthquake is imminent.
[86]
Contemporary depictions of earthquakes in film are variable in the manner in which they reflect human psychological reactions to the actual trauma that can be caused to directly afflicted families and their loved ones.
[87]
Disaster mental health response research emphasizes the need to be aware of the different roles of loss of family and key community members, loss of home and familiar surroundings, and loss of essential supplies and services to maintain survival.
[88]
[89]
Particularly for children, the clear availability of caregiving adults who can protect, nourish, and clothe them in the aftermath of the earthquake and help them make sense of what has befallen them has been shown to be more important to their emotional and physical health than the simple giving of provisions.
[90]
As was observed after other disasters involving destruction and loss of life and their media depictions, recently observed in the
2010 Haiti earthquake
, it is also believed to be important not to pathologize the reactions to loss and displacement or disruption of governmental administration and services, but rather to validate the reactions to support constructive problem-solving and reflection.
[91]
Outside of earth
Phenomena similar to earthquakes have been observed in other planets (e.g.,
marsquakes
on Mars) and on the Moon (e.g.,
moonquakes
).
See also
References
- ^
"USGS: Magnitude 8 and Greater Earthquakes Since 1900"
. Archived from
the original
on April 14, 2016.
- ^
"Earthquakes with 50,000 or More Deaths"
. U.S. Geological Survey. Archived from
the original
on November 1, 2009.
- ^
Spignesi, Stephen J. (2005).
Catastrophe!: The 100 Greatest Disasters of All Time
.
ISBN
0-8065-2558-4
- ^
a
b
"Cool Earthquake Facts"
. United States Geological Survey.
Archived
from the original on 2021-04-20
. Retrieved
2021-04-21
.
- ^
a
b
Pressler, Margaret Webb (14 April 2010). "More earthquakes than usual? Not really".
KidsPost
. Washington Post: Washington Post. pp. C10.
- ^
Kanamori Hiroo.
"The Energy Release in Great Earthquakes"
(PDF)
. Journal of Geophysical Research. Archived from
the original
(PDF)
on 2010-07-23
. Retrieved
2010-10-10
.
- ^
USGS.
"How Much Bigger?"
. United States Geological Survey.
Archived
from the original on 2011-06-07
. Retrieved
2010-10-10
.
- ^
Ohnaka, M. (2013).
The Physics of Rock Failure and Earthquakes
. Cambridge University Press. p. 148.
ISBN
978-1-107-35533-0
.
- ^
Vassiliou, Marius; Kanamori, Hiroo (1982). "The Energy Release in Earthquakes".
Bull. Seismol. Soc. Am
.
72
: 371?387.
- ^
Spence, William; S.A. Sipkin; G.L. Choy (1989).
"Measuring the Size of an Earthquake"
. United States Geological Survey. Archived from
the original
on 2009-09-01
. Retrieved
2006-11-03
.
- ^
Sibson, R.H. (1982). "Fault Zone Models, Heat Flow, and the Depth Distribution of Earthquakes in the Continental Crust of the United States".
Bulletin of the Seismological Society of America
.
72
(1): 151?163.
- ^
Sibson, R.H. (2002) "Geology of the crustal earthquake source" International handbook of earthquake and engineering seismology, Volume 1, Part 1, p. 455, eds. W H K Lee, H Kanamori, P C Jennings, and C. Kisslinger, Academic Press,
ISBN
978-0-12-440652-0
- ^
Hjaltadottir S., 2010, "Use of relatively located microearthquakes to map fault patterns and estimate the thickness of the brittle crust in Southwest Iceland"
- ^
"Reports and publications | Seismicity | Icelandic Meteorological office"
. En.vedur.is.
Archived
from the original on 2008-04-14
. Retrieved
2011-07-24
.
- ^
Stern, Robert J. (2002), "Subduction zones",
Reviews of Geophysics
,
40
(4): 17,
Bibcode
:
2002RvGeo..40.1012S
,
doi
:
10.1029/2001RG000108
,
S2CID
247695067
- ^
"Instrumental California Earthquake Catalog"
. WGCEP. Archived from
the original
on 2011-07-25
. Retrieved
2011-07-24
.
- ^
Schorlemmer, D.; Wiemer, S.; Wyss, M. (2005). "Variations in earthquake-size distribution across different stress regimes".
Nature
.
437
(7058): 539?542.
Bibcode
:
2005Natur.437..539S
.
doi
:
10.1038/nature04094
.
PMID
16177788
.
S2CID
4327471
.
- ^
Geoscience Australia.
[
full citation needed
]
- ^
Wyss, M. (1979). "Estimating expectable maximum magnitude of earthquakes from fault dimensions".
Geology
.
7
(7): 336?340.
Bibcode
:
1979Geo.....7..336W
.
doi
:
10.1130/0091-7613(1979)7<336:EMEMOE>2.0.CO;2
.
- ^
"Global Centroid Moment Tensor Catalog"
. Globalcmt.org.
Archived
from the original on 2011-07-19
. Retrieved
2011-07-24
.
- ^
"M7.5 Northern Peru Earthquake of 26 September 2005"
(PDF)
.
National Earthquake Information Center
. 17 October 2005.
Archived
(PDF)
from the original on 25 May 2017
. Retrieved
2008-08-01
.
- ^
Greene II, H.W.; Burnley, P.C. (October 26, 1989). "A new self-organizing mechanism for deep-focus earthquakes".
Nature
.
341
(6244): 733?737.
Bibcode
:
1989Natur.341..733G
.
doi
:
10.1038/341733a0
.
S2CID
4287597
.
- ^
Foxworthy and Hill (1982).
Volcanic Eruptions of 1980 at Mount St. Helens, The First 100 Days: USGS Professional Paper 1249
.
- ^
Watson, John; Watson, Kathie (January 7, 1998).
"Volcanoes and Earthquakes"
. United States Geological Survey.
Archived
from the original on March 26, 2009
. Retrieved
May 9,
2009
.
- ^
a
b
National Research Council (U.S.). Committee on the Science of Earthquakes (2003).
"5. Earthquake Physics and Fault-System Science"
.
Living on an Active Earth: Perspectives on Earthquake Science
. Washington, D.C.: National Academies Press. p.
418
.
ISBN
978-0-309-06562-7
. Retrieved
8 July
2010
.
- ^
Melgar, Diego; Taymaz, Tuncay; Ganas, Athanassios; Crowell, Brendan; Ocalan, Taylan; Kahraman, Metin; Tsironi, Varvara; Yolsal-Cevikbilen, Seda; Valkaniotis, Sotiris; Irmak, Tahir Serkan; Eken, Tuna; Erman, Ceyhun; Ozkan, Berkan; Dogan, Ali Hasan; Altunta?, Cemali (2023).
"Sub- and super-shear ruptures during the 2023 Mw 7.8 and Mw 7.6 earthquake doublet in SE Turkiye"
.
Seismica
.
2
(3): 387.
Bibcode
:
2023Seism...2..387M
.
doi
:
10.26443/seismica.v2i3.387
.
S2CID
257520761
.
- ^
Sibson, R.H. (1973). "Interactions between Temperature and Pore-Fluid Pressure during Earthquake Faulting and a Mechanism for Partial or Total Stress Relief".
Nat. Phys. Sci
.
243
(126): 66?68.
Bibcode
:
1973NPhS..243...66S
.
doi
:
10.1038/physci243066a0
.
- ^
Rudnicki, J.W.; Rice, J.R. (2006).
"Effective normal stress alteration due to pore pressure changes induced by dynamic slip propagation on a plane between dissimilar materials"
(PDF)
.
J. Geophys. Res
. 111, B10308 (B10).
Bibcode
:
2006JGRB..11110308R
.
doi
:
10.1029/2006JB004396
.
S2CID
1333820
.
Archived
(PDF)
from the original on 2019-05-02.
- ^
a
b
c
Guerriero, V; Mazzoli, S. (2021).
"Theory of Effective Stress in Soil and Rock and Implications for Fracturing Processes: A Review"
.
Geosciences
.
11
(3): 119.
Bibcode
:
2021Geosc..11..119G
.
doi
:
10.3390/geosciences11030119
.
- ^
a
b
Nur, A; Booker, J.R. (1972). "Aftershocks Caused by Pore Fluid Flow?".
Science
.
175
(4024): 885?887.
Bibcode
:
1972Sci...175..885N
.
doi
:
10.1126/science.175.4024.885
.
PMID
17781062
.
S2CID
19354081
.
- ^
a
b
c
"What are Aftershocks, Foreshocks, and Earthquake Clusters?"
. Archived from
the original
on 2009-05-11.
- ^
"Repeating Earthquakes"
. United States Geological Survey. January 29, 2009.
Archived
from the original on April 3, 2009
. Retrieved
May 11,
2009
.
- ^
"The Parkfield, California, Earthquake Experiment"
.
earthquake.usgs.gov
.
Archived
from the original on 2022-10-24
. Retrieved
2022-10-24
.
- ^
a
b
"Aftershock | geology"
.
Encyclopedia Britannica
.
Archived
from the original on 2015-08-23
. Retrieved
2021-10-13
.
- ^
"Earthquake Swarms at Yellowstone"
. United States Geological Survey.
Archived
from the original on 2008-05-13
. Retrieved
2008-09-15
.
- ^
Duke, Alan.
"Quake 'swarm' shakes Southern California"
. CNN.
Archived
from the original on 27 August 2012
. Retrieved
27 August
2012
.
- ^
Amos Nur; Cline, Eric H. (2000).
"Poseidon's Horses: Plate Tectonics and Earthquake Storms in the Late Bronze Age Aegean and Eastern Mediterranean"
(PDF)
.
Journal of Archaeological Science
.
27
(1): 43?63.
Bibcode
:
2000JArSc..27...43N
.
doi
:
10.1006/jasc.1999.0431
.
ISSN
0305-4403
. Archived from
the original
(PDF)
on 2009-03-25.
- ^
"Earthquake Storms"
.
Horizon
. 1 April 2003.
Archived
from the original on 2019-10-16
. Retrieved
2007-05-02
.
- ^
"
Italy's earthquake history
" (
Archived
2004-07-09 at the
Wayback Machine
). BBC News. October 31, 2002.
- ^
"Earthquake Hazards Program"
. United States Geological Survey.
Archived
from the original on 2011-05-13
. Retrieved
2006-08-14
.
- ^
"USGS Earthquake statistics table based on data since 1900"
. Archived from
the original
on May 24, 2010.
- ^
"Seismicity and earthquake hazard in the UK"
. Quakes.bgs.ac.uk.
Archived
from the original on 2010-11-06
. Retrieved
2010-08-23
.
- ^
"Common Myths about Earthquakes"
. United States Geological Survey. Archived from
the original
on 2006-09-25
. Retrieved
2006-08-14
.
- ^
Are Earthquakes Really on the Increase?
Archived
2014-06-30 at the
Wayback Machine
, USGS Science of Changing World. Retrieved 30 May 2014.
- ^
"Earthquake Facts and Statistics: Are earthquakes increasing?"
. United States Geological Survey. Archived from
the original
on 2006-08-12
. Retrieved
2006-08-14
.
- ^
The 10 biggest earthquakes in history
Archived
2013-09-30 at the
Wayback Machine
, Australian Geographic, March 14, 2011.
- ^
"Historic Earthquakes and Earthquake Statistics: Where do earthquakes occur?"
. United States Geological Survey. Archived from
the original
on 2006-09-25
. Retrieved
2006-08-14
.
- ^
"Visual Glossary ? Ring of Fire"
. United States Geological Survey. Archived from
the original
on 2006-08-28
. Retrieved
2006-08-14
.
- ^
Jackson, James (2006).
"Fatal attraction: living with earthquakes, the growth of villages into megacities, and earthquake vulnerability in the modern world"
.
Philosophical Transactions of the Royal Society
.
364
(1845): 1911?1925.
Bibcode
:
2006RSPTA.364.1911J
.
doi
:
10.1098/rsta.2006.1805
.
PMID
16844641
.
S2CID
40712253
.
Archived
from the original on 2013-09-03
. Retrieved
2011-03-09
.
- ^
"
Global urban seismic risk
Archived
2011-09-20 at the
Wayback Machine
." Cooperative Institute for Research in Environmental Science.
- ^
Fougler, Gillian R.
; Wilson, Miles; Gluyas, Jon G.; Julian, Bruce R.; Davies, Richard J. (2018).
"Global review of human-induced earthquakes"
.
Earth-Science Reviews
.
178
: 438?514.
Bibcode
:
2018ESRv..178..438F
.
doi
:
10.1016/j.earscirev.2017.07.008
.
- ^
Fountain, Henry (March 28, 2013).
"Study Links 2011 Quake to Technique at Oil Wells"
.
The New York Times
.
The New York Times
.
Archived
from the original on July 23, 2020
. Retrieved
July 23,
2020
.
- ^
Hough, Susan E.
; Page, Morgan (2015).
"A Century of Induced Earthquakes in Oklahoma?"
.
Bulletin of the Seismological Society of America
.
105
(6): 2863?2870.
Bibcode
:
2015BuSSA.105.2863H
.
doi
:
10.1785/0120150109
.
Archived
from the original on July 23, 2020
. Retrieved
July 23,
2020
.
- ^
Klose, Christian D. (July 2012). "Evidence for anthropogenic surface loading as trigger mechanism of the 2008 Wenchuan earthquake".
Environmental Earth Sciences
.
66
(5): 1439?1447.
arXiv
:
1007.2155
.
Bibcode
:
2012EES....66.1439K
.
doi
:
10.1007/s12665-011-1355-7
.
S2CID
118367859
.
- ^
LaFraniere, Sharon (February 5, 2009).
"Possible Link Between Dam and China Quake"
.
The New York Times
.
The New York Times
.
Archived
from the original on January 27, 2018
. Retrieved
July 23,
2020
.
- ^
Earle, Steven (September 2015).
"11.3 Measuring Earthquakes"
.
Physical Geology
(2nd ed.).
Archived
from the original on 2022-10-21
. Retrieved
2022-10-22
.
- ^
Chung & Bernreuter 1980
, p. 1.
- ^
"USGS Earthquake Magnitude Policy (implemented on January 18, 2002)"
.
Earthquake Hazards Program
. USGS. Archived from
the original
on 2016-05-04.
A copy can be found at
"USGS Earthquake Magnitude Policy"
.
Archived
from the original on 2017-07-31
. Retrieved
2017-07-25
.
- ^
Bormann, P; Di Giacomo, D (2011).
"The moment magnitude Mw and the energy magnitude Me: common roots and differences"
.
Journal of Seismology
.
15
(2): 411?427.
doi
:
10.1007/s10950-010-9219-2
– via Springer Link.
- ^
"Speed of Sound through the Earth"
. Hypertextbook.com.
Archived
from the original on 2010-11-25
. Retrieved
2010-08-23
.
- ^
"Newsela | The science of earthquakes"
.
newsela.com
.
Archived
from the original on 2017-03-01
. Retrieved
2017-02-28
.
- ^
Geographic.org.
"Magnitude 8.0 ? SANTA CRUZ ISLANDS Earthquake Details"
.
Global Earthquake Epicenters with Maps
.
Archived
from the original on 2013-05-14
. Retrieved
2013-03-13
.
- ^
"Earth's gravity offers earlier earthquake warnings"
.
Archived
from the original on 2016-11-23
. Retrieved
2016-11-22
.
- ^
"Gravity shifts could sound early earthquake alarm"
. Archived from
the original
on 2016-11-24
. Retrieved
2016-11-23
.
- ^
"On Shaky Ground, Association of Bay Area Governments, San Francisco, reports 1995,1998 (updated 2003)"
. Abag.ca.gov. Archived from
the original
on 2009-09-21
. Retrieved
2010-08-23
.
- ^
"Guidelines for evaluating the hazard of surface fault rupture, California Geological Survey"
(PDF)
. California Department of Conservation. 2002. Archived from
the original
(PDF)
on 2009-10-09.
- ^
"Historic Earthquakes ? 1964 Anchorage Earthquake"
. United States Geological Survey. Archived from
the original
on 2011-06-23
. Retrieved
2008-09-15
.
- ^
"The wicked problem of earthquake hazard in developing countries"
.
www.preventionweb.net
. 7 March 2018.
Archived
from the original on 2022-11-03
. Retrieved
2022-11-03
.
- ^
"Earthquake Resources"
. Nctsn.org. 30 January 2018.
Archived
from the original on 2018-03-21
. Retrieved
2018-06-05
.
- ^
"Natural Hazards ? Landslides"
. United States Geological Survey.
Archived
from the original on 2010-09-05
. Retrieved
2008-09-15
.
- ^
"The Great 1906 San Francisco earthquake of 1906"
. United States Geological Survey. Archived from
the original
on 2017-02-11
. Retrieved
2008-09-15
.
- ^
a
b
Noson, L.L.; Qamar, A.; Thorsen, G.W. (1988).
Washington Division of Geology and Earth Resources Information Circular 85
(PDF)
. Washington State Earthquake Hazards.
Archived
(PDF)
from the original on 2020-02-04
. Retrieved
2019-12-01
.
- ^
"Notes on Historical Earthquakes"
.
British Geological Survey
. Archived from
the original
on 2011-05-16
. Retrieved
2008-09-15
.
- ^
"Fresh alert over Tajik flood threat"
.
BBC News
. 2003-08-03.
Archived
from the original on 2008-11-22
. Retrieved
2008-09-15
.
- ^
Geller et al. 1997
, p. 1616, following
Allen (1976
, p. 2070), who in turn followed
Wood & Gutenberg (1935)
- ^
Earthquake Prediction
Archived
2009-10-07 at the
Wayback Machine
. Ruth Ludwin, U.S. Geological Survey.
- ^
Kanamori 2003
, p. 1205. See also
International Commission on Earthquake Forecasting for Civil Protection 2011
, p. 327.
- ^
Working Group on California Earthquake Probabilities in the San Francisco Bay Region, 2003 to 2032, 2003,
"Bay Area Earthquake Probabilities"
. Archived from
the original
on 2017-02-18
. Retrieved
2017-08-28
.
- ^
Pailoplee, Santi (2017-03-13).
"Probabilities of Earthquake Occurrences along the Sumatra-Andaman Subduction Zone"
.
Open Geosciences
.
9
(1): 4.
Bibcode
:
2017OGeo....9....4P
.
doi
:
10.1515/geo-2017-0004
.
ISSN
2391-5447
.
S2CID
132545870
.
- ^
Salvaneschi, P.; Cadei, M.; Lazzari, M. (1996). "Applying AI to Structural Safety Monitoring and Evaluation".
IEEE Expert
.
11
(4): 24?34.
doi
:
10.1109/64.511774
.
- ^
a
b
c
d
"Earthquakes".
Encyclopedia of World Environmental History
. Vol. 1: A?G. Routledge. 2003. pp. 358?364.
- ^
Sturluson, Snorri
(1220).
Prose Edda
.
ISBN
978-1-156-78621-5
.
- ^
George E. Dimock (1990).
The Unity of the Odyssey
. Univ of Massachusetts Press. pp. 179?.
ISBN
978-0-87023-721-8
.
- ^
"Namazu"
.
World History Encyclopedia
. Retrieved
2017-07-23
.
- ^
a
b
c
d
Van Riper, A. Bowdoin (2002).
Science in popular culture: a reference guide
. Westport:
Greenwood Press
. p.
60
.
ISBN
978-0-313-31822-1
.
- ^
JM Appel. A Comparative Seismology. Weber Studies (first publication), Volume 18, Number 2.
- ^
Goenjian, Najarian; Pynoos, Steinberg; Manoukian, Tavosian; Fairbanks, AM; Manoukian, G; Tavosian, A; Fairbanks, LA (1994). "Posttraumatic stress disorder in elderly and younger adults after the 1988 earthquake in Armenia".
Am J Psychiatry
.
151
(6): 895?901.
doi
:
10.1176/ajp.151.6.895
.
PMID
8185000
.
- ^
Wang, Gao; Shinfuku, Zhang; Zhao, Shen; Zhang, H; Zhao, C; Shen, Y (2000). "Longitudinal Study of Earthquake-Related PTSD in a Randomly Selected Community Sample in North China".
Am J Psychiatry
.
157
(8): 1260?1266.
doi
:
10.1176/appi.ajp.157.8.1260
.
PMID
10910788
.
- ^
Goenjian, Steinberg; Najarian, Fairbanks; Tashjian, Pynoos (2000).
"Prospective Study of Posttraumatic Stress, Anxiety, and Depressive Reactions After Earthquake and Political Violence"
(PDF)
.
Am J Psychiatry
.
157
(6): 911?916.
doi
:
10.1176/appi.ajp.157.6.911
.
PMID
10831470
. Archived from
the original
(PDF)
on 2017-08-10.
- ^
Coates, SW
;
Schechter, D
(2004). "Preschoolers' traumatic stress post-9/11: relational and developmental perspectives. Disaster Psychiatry Issue".
Psychiatric Clinics of North America
.
27
(3): 473?489.
doi
:
10.1016/j.psc.2004.03.006
.
PMID
15325488
.
- ^
Schechter, DS
;
Coates, SW
; First, E (2002). "Observations of acute reactions of young children and their families to the World Trade Center attacks".
Journal of ZERO-TO-THREE: National Center for Infants, Toddlers, and Families
.
22
(3): 9?13.
Sources
- Allen, Clarence R. (December 1976), "Responsibilities in earthquake prediction",
Bulletin of the Seismological Society of America
,
66
(6): 2069?2074,
Bibcode
:
1976BuSSA..66.2069A
,
doi
:
10.1785/BSSA0660062069
.
- Bolt, Bruce A. (1993),
Earthquakes and geological discovery
, Scientific American Library,
ISBN
978-0-7167-5040-6
.
- Chung, D.H.; Bernreuter, D.L. (1980),
Regional Relationships Among Earthquake Magnitude Scales.
,
doi
:
10.2172/5073993
,
OSTI
5073993
,
archived
from the original on 2020-01-22
, retrieved
2017-07-21
, NUREG/CR-1457.
- Deborah R. Coen.
The Earthquake Observers: Disaster Science From Lisbon to Richter
(
University of Chicago Press
; 2012) 348 pages; explores both scientific and popular coverage
- Geller, Robert J.; Jackson, David D.; Kagan, Yan Y.; Mulargia, Francesco (14 March 1997),
"Earthquakes Cannot Be Predicted"
(PDF)
,
Science
,
275
(5306): 1616,
doi
:
10.1126/science.275.5306.1616
,
S2CID
123516228
, archived from
the original
(PDF)
on 12 May 2019
, retrieved
29 December
2016
.
- International Commission on Earthquake Forecasting for Civil Protection (30 May 2011),
"Operational Earthquake Forecasting: State of Knowledge and Guidelines for Utilization"
(PDF)
,
Annals of Geophysics
,
54
(4): 315?391,
doi
:
10.4401/ag-5350
,
S2CID
129825964
,
archived
(PDF)
from the original on 17 July 2021
.
- Kanamori, Hiroo (2003), "Earthquake Prediction: An Overview",
International Handbook of Earthquake and Engineering Seismology
, International Geophysics,
616
: 1205?1216,
doi
:
10.1016/s0074-6142(03)80186-9
,
ISBN
978-0-12-440658-2
.
- Wood, H.O.; Gutenberg, B. (6 September 1935), "Earthquake prediction",
Science
,
82
(2123): 219?320,
Bibcode
:
1935Sci....82..219W
,
doi
:
10.1126/science.82.2123.219
,
PMID
17818812
.
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