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A sudden movement of the Earth's lithosphere (its crust and upper mantle). 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. A Closer Look Fractures in Earth's crust, or lithosphere, where sections of rock have slipped past each other are called faults. Earthquakes are caused by the sudden release of accumulated strain along these faults, releasing energy in the form of low-frequency sound waves called seismic waves. Although thousands of earthquakes occur each year, most are too weak to be detected except byseismographs, instruments that detect and record vibrations and movements in the Earth. The point where the earthquake originates is the seismic focus, and directly above it on Earth's surface is the earthquake's epicenter. 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 Earth, reflecting off the surfaces of its various layers. S waves cannot travel through the liquid outer core. Surface (L) waves named after the nineteenth-century British mathematician A.E.H. Love travel along Earth's surface, causing most of the damage of an earthquake. The total amount of energy released by an earthquake is measured on the Richter scale. Each increase by 1 corresponds to a tenfold increase in strength. Earthquakes above 7 on the Richter scale are considered severe. The famous earthquake that flattened San Francisco in 1906 had a magnitude of 7.8.

Earthquake

Primary and secondary waves radiate from an earthquake's focus and move through the Earth's interior. As they encounter a boundary, like that between the lower mantle and the liquid outer core, they are reflected and refracted. Secondary waves cannot travel through liquids. Surface waves radiate out from an earthquake's focus and travel only along the Earth's surface. An earthquake is a natural phenomenon like rain. Earthquakes have occurred for billions of years. Descriptions as old as recorded history show the significant effects they have had on people’s lives. Long before there were scientific theories for the cause of earthquakes, people around the world created folklore to explain. In simple terms, earthquakes are caused by the constant motion of Earth’s surface. This motion creates buildup and releases energy stored in rocks at and near the Earth’s surface. Earthquakes are the sudden, rapid shaking of the Earth as this energy is released. An earthquake is a natural occurrence, like rain. Earthquakes affect almost every part of the Earth and like rain they can be either mild or catastrophic. Over the course of geological time, earthquakes, floods, and other natural events have helped to shape the surface of our planet. An earthquake may last only a few seconds, but the processes that cause earthquakes have operated within the Earth for millions and millions of years. Until very recently, the cause of earthquakes was an unsolved mystery. It was the subject of fanciful folklore and equally fanciful learned speculation by peoples throughout the world. An earthquake is a sudden, rapid shaking of the Earth caused by the release of energy stored in rocks. This is a brief definition which students of all ages can master. A full definition of the term, however, would need to include a good deal more information. Students may be surprised that we speak of rocks and rock layers, because in many places the rock material of the Earth’s crust is covered by accumulations of sand or soil. Remind them that even beneath the sediment in river valleys, plains, and beach areas, some kind of rock are always present. An earthquake (also known as a quake, tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time. Earthquakes are measured using observations from seismometers. The moment magnitude is the most common scale on which earthquakes larger than approximately 5 are reported for the entire globe. The more numerous earthquakes smaller than magnitude 5 reported by national seismological observatories are measured mostly on the local magnitude scale, also referred to as the Richter scale. These two scales are numerically similar over their range of validity. Magnitude 3 or lower earthquakes are mostly almost imperceptible or weak and magnitude 7 and over potentially cause serious damage over larger areas, depending on their depth. The largest earthquakes in historic times have been of magnitude slightly over 9, although there is no limit to the possible magnitude. The most recent large earthquake of magnitude 9.0 or larger was a 9.0 magnitude earthquake in Japan in 2011 (as of October 2012), and it was the largest Japanese earthquake since records began. Intensity of shaking is measured on the modified Mercalli scale. The shallower an earthquake, the more damage to structures it causes, all else being equal.[1] At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacement of the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes can also trigger landslides, and occasionally volcanic activity. In its most general sense, the word earthquake is used to describe any seismic event — whether natural or caused by humans — that generates seismic waves. Earthquakes are caused mostly by rupture of geological faults, but also by other events such as volcanic activity, landslides, mine blasts, and nuclear tests. An earthquake's point of initial rupture is called its focus or hypocenter. The epicenteris the point at ground level directly above the hypocenter.

History of Earthquakes

Earthquakes have been recorded as early as 1177 B.C. in China. Of course earthquakes have been a part of myth and legend since the dawn of man. In Greek Mythology, Posseidon (Neptune in the Roman pantheon) was "God of the Sea". Yet one of his powers was thought to be that of "earth shaker". As a tsunami is often the result of an earthquake, this was an appropriate power for a sea god. In European history, the earliest recorded earthquake occurred in 580 B.C. In North America the great earthquakes of 1811-1812 occurred near New Madrid, Missouri. The magnitude of the quakes are not known, but they are estimated to have been about 8 on the Richter scale. There were actually three large quakes with aftershocks between and for months after. The quake was so wide-spread it was felt as far away as Boston. The most destructive quake in U.S. history occurred in San Francisco in 1906, it caused the deaths of over 700 people. The great Alaskan earthquake of 1964 was twice as powerful, but less destructive due to the low population density of the area struck. The Chilean quake of 1960 was the biggest quake ever recorded. It came in at 9.5 on the Richter scale. The study of earthquakes is called seismology. The earliest seismologists were the Chinese who worked hard to record their quakes in detail. They even developed a means to predict earthquakes by filling a ceramic jar to the brim with water and leaving it set. If the water overflowed the jar, then an earthquake was imminent. Of course, this means of prediction was unreliable and uncertain. It is thought that some animals may feel vibrations from a quake before humans, and that even minutes before a quake dogs may howl and birds fly erratically. However, evidence for such sensitivity by animals is purely anecdotal. Aristotle was one of the first Europeans to create a theory about the origin of Earthquakes. He thought that they were the result of heavy winds. Not much more study was concentrated on earthquakes until the mid-1700s when London was hit by a devastating quake and a tsunami struck Lisbon, Portugal shortly after. John Mitchell in England and Elie Bertrand in Switzerland began a comprehensive study of the timing and severity of earthquakes. Soon scientists from several countries were exchanging observations and theories on earthquakes. In the 1820's Chile became an area of interest to seismologists. After an earthquake there, it was noticed that the elevation of the coastline had changed. This was substantiated by the Captain of the H.M.S. Beagle, Robert Fitzroy. (The ship also carried Charles Darwin who was studying the flora and fauna of the coast.) In the 1850s Robert Mallet, figured out a means to measure the velocity of seismic waves. Meanwhile, in Italy, Luigi Palmieri invented an electromagnetic seismograph, one of which was installed near Mount Vesuvius and another at the University of Naples. These seismographs were the first seismic instruments capable of routinely detecting earthquakes imperceptible to human beings. 10 Largest Magnitude Earthquakes in Recorded History

1. Valdivia, Chile 22 May 1960 (magnitude 9.5) This earthquake killed 1655 people, injured 3000 and displaced two million. It caused US$550 million damage in Chile, while the tsunami that it spawned caused deaths and damage as far away as Hawaii, Japan and the Philippines. The 'rupture zone' of the quake was more than 1000 km long. Two days after the initial quake, the nearby volcano Puyehue erupted, sending ash and steam up to 6 km into the atmosphere over a period of several weeks.

2.Prince William Sound, Alaska 28 March 1964 (magnitude 9.2) Compared to the Chilean earthquake, this earthquake was less damaging: the resulting tsunami took 128 lives and caused overall US$311 million in damage. The earthquake was felt mainly over Alaska, as well as some places in Canada, while the tsunami created by it caused damage as far away as Hawaii. The most damage was sustained by the city of Anchorage, 120 km north-west of the epicentre. Shaking from the quake itself is reported to have lasted for three minutes.

3.Sumatra, Indonesia 26 December 2004 (magnitude 9.1) In terms of damage and loss of life, the scale of the disaster caused by the resulting Boxing Day Tsunami was enormous. In total, 227,900 people were killed or presumed dead, with around 1.7 million displaced over 14 countries in South Asia and East Africa. The epicentre was 250 km south-east of Band Aceh, Indonesia, at a depth of 30 km. Several days later on 28 December, a mud volcano began erupting near Baratang, Andamar Islands, which is thought to have been associated with the earthquake.jjjj

4.Sendai, Japan 11 March 2011 (magnitude 9.0) So far the official death toll stands at several thousand from the combined effect of the powerful earthquake, aftershocks and the tsunami. However, the total is expected to rise, with some estimates of a final toll of over 10,000. Economic impacts are expected to be huge, with the shutting down of nuclear reactors which many industries rely on for power.

5.Kamchatka, Russia 4 November 1952 (magnitude 9.0) This earthquake generated a tsunami that caused widespread damage in the Hawaiian Islands. Property damage was estimated at around US$1,000,000. Some reports describe waves of over 9 m high at Kaena Point, Oahu. A farmer on Oahu reported the loss of six cows to the tsunami, but no people were reported killed.

6. Bio-bio, Chile 27 February 2010 (magnitude 8.8) This earthquake and subsequent tsunami killed at least 521 people, with 56 missing and 12,000 injured. More than 800,000 people were displaced with a total of 1.8m people affected across Chile, where damage was estimated at US$30 billion. The epicentre was 335 km south-west of Santiago, at a depth of 35 km. A minor tsunami travelled across the Pacific causing damage to boats as far away as San Diego, California.

7.Off the coast of Ecuador 31 January 1906 (magnitude 8.8) This earthquake caused a tsunami that is reported to have killed between 500 and 1,500 in Ecuador and Colombia. The tsunami travelled as far north as San Francisco, on the west coast of the US, and west to Hawaii and Japan. The tsunami took roughly 12 hours to cross the Pacific to Hilo, Hawaii.

8.Rat Islands, Alaska 2 April 1965 (magnitude 8.7) The worst of the damage attributed to this earthquake was caused by a tsunami, reported to be about 10 m high on Shemya Island. The wave caused flooding on Amchitka Island, causing US$10,000 in property damage. No deaths or injuries were reported.

9.Sumatra, Indonesia 28 March 2005 (magnitude 8.6) This earthquake killed 1313, with over 400 people injured by the tsunami as far away as Sri Lanka. The epicentre was 205 km north-west of Sibolga, Sumatra, at a depth of 30 km. This region, also the site of the 2004 Boxing Day Tsunami, is particularly geologically active, with three of the 15 biggest known earthquakes having happened here.

10.Assam - Tibet 15 August 1950 (magnitude 8.6) This inland earthquake caused widespread damages to buildings as well as large landslides. 780 people were killed in eastern Tibet, with many villages and towns affected across Assam, China, Tibet and India. Oscillations to lake levels occurred as far away as Norway. The total death toll is likely to be higher, as no definitive total was ever estimated. While the earthquake itself is known as the Assam Earthquake, it is believed the epicentre may have been in Tibet.

In 1872 a U.S. scientist named Grove Gilbert figured out that earthquakes usually center around a fault line. It was after the 1906 earthquake in San Francisco that Harry Reid hypothesized that earthquakes were likely the result of a build-up of pressure along these faults.

It was about 1910 that Alfred Wegener published his theory of plate tectonics to explain volcanic and seismic activity.

Since then, seismologists have continued to work at a furious pace, building better instruments, computer models, theories and forecast to study the causes and effects of earthquakes.

Causes of Earthquake

There are three main types of fault, all of which may cause an 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 movement on them involves a vertical component. Normal faults occur mainly in areas where the crust is being extended such as a divergent boundary. Reverse faults occur in areas where the crust is being shortened such as at a convergent boundary.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. Many earthquakes are caused by movement on faults that have components of both dip-slip and strike-slip; this is known as oblique slip. (1) Soil Type and Shaking Hazard in the San Francisco Bay Area Ground shaking is the primary cause of earthquake damage to man-made structures. When the ground shakes strongly, buildings can be damaged or destroyed and their occupants may be injured or killed. Seismologists have observed that some districts tend to repeatedly experience stronger seismic shaking than others. This is because the ground under these districts is relatively soft. Soft soils amplify ground shaking. If you live in an area that in past earthquakes suffered shaking stronger than that felt in other areas at comparable distance from the source, you are likely to experience relatively strong shaking in future earthquakes as well. An example of this effect was observed in San Francisco, where many of the same neighborhoods were heavily damaged in both the 1906 and 1989 earthquakes. The influence of the underlying soil on the local amplification of earthquake shaking is called the site effect. Other factors influence the strengh of earthquake shaking at a site as well, including the earthquake's magnitude and the site's proximity to the fault. These factors vary from earthquake to earthquake. In contrast, soft soil always amplifies shear waves. If an earthquake is strong enough and close enough to cause damage, the damage will usually be more severe on soft soils. (2) Nuclear test Nuclear blasts can create tremors but they are distinct from those caused by natural earthquakes. There were early concerns about earthquakes arising as a result of underground tests. However, fault movements and ground fractures have been reported, and explosions often precede a series of aftershocks, thought to be a result of cavity collapse and chimney formation

Effects of Earthquakes

Environmental Effects

Direct Shaking Hazards and Human-Made Structures

Most earthquake-related deaths are caused by the collapse of structures and the construction practices play a tremendous role in the death toll of an earthquake. In southern Italy in 1909 more than 100,000 people perished in an earthquake that struck the region. Almost half of the people living in the region of Messina were killed due to the easily collapsible structures that dominated the villages of the region. A larger earthquake that struck San Francisco three years earlier had killed fewer people (about 700) because building construction practices were different type (predominantly wood). Survival rates in the San Francisco earthquake was about 98%, that in the Messina earthquake was between 33% and 45%) (Zebrowski, 1997). Building practices can make all the difference in earthquakes, even a moderate rupture beneath a city with structures unprepared for shaking can produce tens of thousands of casualties. Although probably the most important, direct shaking effects are not the only hazard associated with earthquakes, other effects such as landslides, liquefaction, and tsunamis have also played important part in destruction produced by earthquakes.

Geologic Effects on Shaking

When we discussed earthquake intensity we discussed some of the basic factors that affect the amplitude and duration of shaking produced by an earthquake (earthquake size, distance from fault, site and regional geology, etc.) and as you are aware, the shaking caused by seismic waves can cause damage buildings or cause buildings to collapse. The level of damage done to a structure depends on the amplitude and the duration of shaking. The amplitudes are largest close to large earthquakes and the duration generally increases with the size of the earthquake (larger quakes shake longer because they rupture larger areas). Regional geology can affect the level and duration of shaking but more important are local site conditions. Although the process can be complicated for strong shaking, generally shaking in soft sediments is larger and longer than when compared with the shaking experienced at a "hard rock" site.

Preparing Structures for Shaking

The first step in preparing structures for shaking is to understand how buildings respond to ground motions- this is the field of study for earthquake and structural engineers. When the ground shakes, buildings respond to the accelerations transmitted from the ground through the structure's foundation. The inertia of the building (it wants to stay at rest) can cause shearing of the structure which can concentrate stresses on the weak walls or joints in the structure resulting in failure or perhaps total collapse. The type of shaking and the frequency of shaking depends on the structure. Tall buildings tend to amplify the motions of longer period motions when compared with small buildings. Each structure has a resonance frequency that is characteristic of the building. Predicting the precise behavior of buildings is complicated, a rule of thumb is that the period of resonance is about equal to 0.1 times the number of stories in the structure. Thus Macelwane Hall resonates at about 0.3 seconds period, and Griesedeck at about 1.4 seconds. Taller buildings also tend to shake longer than short buildings, which can make them relatively more susceptible to damage. Fortunately many tall buildings are constructed to withstand strong winds and some precautions have been taken to reduce their tendency to shake. And they can be made resistant to earthquake vibrations. In many regions of limited resources and/or old structures, the structures are not very well suited to earthquake induced strains and collapse of adobe-style construction has caused thousands of deaths in the last decade. The worst possible structure for earthquake regions is the unreinforced masonry (which is common in the St. Louis area).

Estimating Hazards

Preparing structures (either new or old) for earthquakes is expensive and the level of investment is a social and political decision. The choice of building design is a compromise between appearance, function, structure, strength, and of course, cost. Standards are instituted through the establishment of Building Codes, which regulate the design and construction of buildings. Most of our building codes are designed to protect first the building occupants, and second the building integrity. Building codes are usually drafted to meet the demands of the expected shaking in a given region that are summarized by seismologists and earthquake engineers in hazards maps. Hazard maps are constructed by examining

• The earthquake history of the region to estimate the probability of an earthquake
• The expected shaking intensity produced by the earthquake (often expressed as a peak acceleration)
• The frequency of the shaking, the distance from the fault
• The regional geology and site conditions

to estimate the maximum level of shaking expected during the lifetime of a building. Constructing accurate hazard maps is a challenge and remains the focus of much Geoscience research. For the Midwest you may want to check out the WWW site of a large multidisciplinary effort to help prepare the eastern US for the low-probability, but high consequence earthquake hazards (check out the Mid-America Earthquake Center).

(Courtesy of Dr. Robert Herrmann, Saint Louis University)

Strengthening Structures

We have two approaches for preparing buildings for earthquakes: you either secure the building components (walls, floors, foundation, etc.) together and have the entire structure behave as a single stiff unit that moves with the ground, or you construct a strong and flexible structure that distorts but doesn't break and absorbs some of the shaking energy. Either approach can be expensive so we cannot build all our structures to withstand the largest possible earthquake. We must make compromises and accept some risk (this is not unlike the risks that we accept every day, driving on a freeway, flying in an airplane, living in flood-prone regions, tornado "alley", hurricane-prone regions, etc.). We need different levels of resistance for different classes of structures. Critical structures such as hospitals, power, water-treatment, and chemical plants, dams, etc. must not only survive the shaking, but must remain in operation. These structure require the largest investment of resources to insure that they can provide services following an earthquake.

More general requirements for other structure include having our buildings

• Sustain little damage in small-to-moderate quakes (M < 5.5)
• Sustain some repairable damage for moderate quakes (5.5 < M < 7.0)
• Not collapse in large earthquakes (M > 7.0)

To insure that we meet these goals we can take a number of steps, beginning with thoughtful and responsible planning and zoning laws. Since we know that sites with soft, water-saturated foundations are prone to damage, we should resist the temptation to build on those sits and we should certainly not put critical structures on such sites, and avoid building on these sites at all if possible. If that's not possible, try to compact the soft sediments before the constructing or anchor the structure in the basement. We can take a number of steps to strengthen buildings including using steel frame construction, adequately securing the structure to the ground through a solid foundation, incorporating shear walls and or cross-bracing into the structure, or more sophisticated approaches such as using rubber or steel pads to isolate the structure from the shaking.

We have talked above seismic waves and how they vibrate the ground which can lead directly to the collapse of structures. There are other, secondary effects that are caused by earthquakes, most often a result of strong shaking. A simple example common in many earthquakes are landslides. The shaking causes regions of the rock and soil to slide downhill. The same material would eventually fail with increased time, but earthquakes trigger many slides that do much bit of damage.

Landslides and Liquefaction

Buildings aren't the only thing to fail under the stresses of seismic waves. Often unstable regions of hillsides or mountains fail. In addition to the obvious hazard posed by large landslides, even non-lethal slides can cause problems when they block highways they can be inconvenient or cause problems for emergency and rescue operations.

Occasionally large landslides can be triggered by earthquakes. In 1970 an earthquake off the coast of Peru produced a landslide than began 80 miles away from the earthquake. The slide was large (witnesses estimated it's height at about 30 meters or 100 feet), traveled at more than one-hundred miles per hour and plowed through part of one village and annihilated another, killing more than 18,000 people. In some cases, when the surface is underlain by a saturated, sand rich layer of soil, prolonged shaking can cause the expulsion of fluid from the sand layer resulting in large "sand blows" that erupt through the overlying strata.

In the 1811-12 earthquakes the sand blows were enormous and covered large regions of the Missouri bootheel. Liquefaction can cause other problems as the soil loses it ability to resist shear and flows much like quick sand. Anything relying on the substrata for support can shift, tilt, rupture, or collapse.

Tsunamis

A sometimes dramatic byproduct of certain types of earthquakes are tsunamis. Tsunami is a Japanese term that means "harbor wave". Tsunamis are frequently confused with tidal waves, but they have nothing to do with the tides, they are the result of a sudden vertical offset in the ocean floor caused by earthquakes, submarine landslides, and volcanic deformation. In 1883 the volcanic eruption of Krakatoa resulted in the collapse of a caldera that initiated a tsunami which killed 36,000 people on nearby islands. On June 25, 1896 an earthquake off the Japanese coast generated a tsunami that hit the shore with wave heights ranging from 10 to 100 feet. As the fishing fleets returned to shore following an overnight trip they found their villages destroyed and 22,000 people dead. In the last century more than 50,000 people have died as a result of tsunamis.

Tsunami Initiation

A sudden offset changes the elevation of the ocean and initiates a water wave that travels outward from the region of sea-floor disruption. Tsunamis can travel all the way across the ocean and large earthquakes in Alaska and Chile have generated waves that caused damage and deaths in regions as far away as California, Hawaii and Japan.

Tsunamis are initiated by a sudden displacement of the ocean, commonly caused by vertical deformation of the ocean floor during earthquakes. Other causes such as deformation by landslides and volcanic processes also generate tsunamis. The speed of this wave depends on the ocean depth and is typically about as fast as a commercial passenger jet (about 0.2 km/s or 712 km/hr). This is relatively slow compared to seismic waves, so we are often alerted to the dangers of the tsunami by the shaking before the wave arrives. The trouble is that the time to react is not very long in regions close to the earthquake that caused the tsunami.

In deep water tsunamis are not large and pose no danger. They are very broad with horizontal wavelengths of hundreds of kilometers and surface heights much much smaller, about one meter. Tsunamis pose no threat in the deep ocean because they are only a meter or so high in deep water. But as the wave approaches the shore and the water shallows, all the energy that was distributed throughout the ocean depth becomes concentrated in the shallow water and the wave height increases.

When a tsunami approaches the shore, the water depth decreases, the front of the wave slows down, the wave grows dramatically, and surges on land. Typical heights for large tsunamis are on the order of 10s of meters and a few have approached 90 meters (about 300 feet). These waves are typically more devastating to the coastal region than the shaking of the earthquake that caused the tsunami. Even the more common tsunamis of about 10-20 meters can "wipe clean" coastal communities. Deadly tsunamis occur about every one to two years and they have at times killed thousands of people. In 1992-93 three large tsunamis occurred: one in Japan, Indonesia, and Nicaragua. All struck at night and devastated the local communities. Social effects

• Disrupt Normal Life.
• Affects a Large number of People.
• Losses to Lives, Livelihoods, Property.
• Loss of housing.
• Damage to infrastructure
• Disruption of transport and communication.
• Disruption of marketing systems.
• Breakdown of social order.
• Loss of business.
• Loss of industrial output.

REFERENCES http://www.australiangeographic.com.au/journal/the-10-biggest-earthquakes-in-recorded-history.htm http://eqseis.geosc.psu.edu/~cammon/HTML/Classes/IntroQuakes/Notes/earthquake_effects.html http://www.bbc.co.uk/schools/gcsebitesize/geography/natural_hazards/earthquakes_rev3.shtml http://www.readinessinfo.com/eqgeography.shtml http://jalandhar.nic.in/html/earthquake_impact.htm

Prevention of Earthquake

Scientists are continuously thinking of ways to try and reduce earthquake power. Some are trying to lessen the friction between colliding plates. They poured water down a fault where two plates were grinding together. The water “lubricated” the fault, letting one piece jerk free with a number of little earthquakes and preventing a large tremor. Special instruments are now in existence to give warnings in California, Japan, and New Zealand. They show if land has begun to shift dangerously on a certain side of a fault. Other instruments are used to detect certain gases collecting in groundwater. Architects are also designing earthquake-proof buildings, constructing on rock instead of gravel, or on soft sand or clay. Large structures are made with strong frameworks of steel or reinforced concrete, so that the frame stands firm even if the ground is shaking. The pyramid-shaped Transamerica building in San Francisco was designed in this fashion. Researchers are always trying to reduce the impact of earthquakes. They continue to study and experiment with ways to tame the Earth. However, we all still have much more to learn before we can control the power of one of nature’s most amazing phenomena. Although it’s not possible to predict earthquakes, appropriate knowledge and preparation can help to minimize damage in an emergency. Below is some recommended preparation for earthquakes. Get to know nearby evacuation sites, such as schools or parks.

Prepare emergency food and water supplies to take during evacuation. Determine how to contact family members and friends or where to gather after a disaster to ensure you can meet up.

Always carry a card with your name, address and phone number as well as information on your blood type and contact numbers for your relatives, friends, workplace and embassy.

Fix furniture to the walls to prevent it from falling when earthquakes occur.

Participate in community disaster drills as often as possible.

The Sapporo International Communication Plaza issues a pamphlet showing what to do in case of an earthquake, and what to prepare ahead of time. This is called the Disaster Prevention Brochure (available in Japanese, English, Chinese, Korean, Russian and Thai), and can also be accessed on the City of Sapporo website.

Be prepared for prevent the earthquake

If a major earthquake strikes, it is possible that lifeline utility services (electricity, water, gas and telephone) will be disrupted. In your home, furniture may topple over. To avoid having a panicky response if an earthquake strikes, it is important to be prepared on an ongoing basis.

• An earthquake does not mean immediate evacuation. Even if a major earthquake strikes, you do not need to evacuate unless there is an outbreak of fire, your house collapses, or a disaster prevention institution announces it is time to evacuate. It is a good idea to prepare an emergency supply of food and drinking water that will last for at least three days, just in case.
• Should the need to evacuate arise, it is a good idea to prepare not only a supply of food and drinking water, but also an emergency pack with the minimum of belongings to take along with you, such as clothes, portable radio, flashlight and valuables.
• We cannot predict when or under what conditions an earthquake will strike. Do you know what you should do, how to contact your family members and where to evacuate? It is a good idea to have a family meeting about disaster prevention at least once a year to discuss evacuation procedures, how to contact each other and delegate certain responsibilities. Furthermore, since the evacuation site (elementary or junior high school) is designated according to your neighborhood association, it is a good idea for family members to walk to the evacuation site and determine a specific evacuation route so that everyone can respond calming when the time comes to evacuate.
• When a major earthquake strikes, furniture such as cupboards and bookshelves may topple over, and their contents — dishes and books — may fly across the room because of the violent tremors. It is a wise idea to brace furniture to a stable column or support in your home to prevent it from falling. If glass from windows or your cupboard shatters, this may cause injuries or be an obstruction to evacuation. Placing shatterproof film on glass surfaces is a good idea.

Earthquake Precautions — 10 Points to Keep in Mind

What to Do If You Feel a Major Tremor

• If You Feel a Tremor—Protect Yourself : If you feel a major tremor, first of all, keep yourself safe until the tremor stops. Next, see what the situation is like before taking the next step.

What to Do during and Immediately after an Earthquake

• Swift Fire Prevention—Turn off All Sources of Heat : There are three instances when you should turn off sources of heat: (1) when you feel a small tremor, (2) when a major tremor subsides, and (3) when a fire breaks out.
• Action Taken in Haste—The Cause of Injuries : Be careful of furniture and pieces of glass that may fall and break indoors.
• Open a Window or Door—Secure a Means of Egress : During a small tremor or after a major tremor has subsided, secure a means of egress in case you need to evacuate the building.
• Falling Objects—Do Not Rush Outside in a Panic : Be careful; tiles, windowpanes, and signs may fall.
• Do Not Go Near Gates or Walls : If you feel a tremor when you are outdoors, avoid going near brick or block walls.

What to Do after an Earthquake

• Accurate Information—Proper Action : Listen to accurate information, such as from the radio, TV, City Office, or Fire Department.
• Before You Evacuate—Check the Gas and Electricity : If you need to evacuate, be sure to turn off the circuit breaker and close the main gas valve before leaving.
• Let’s Check On One Another—Checking On the Safety of Family Members : After checking on the safety of family members, check on the safety of your neighbors.
• Help One Another— Rescue and First Aid : Help neighbors rescue those who are buried under collapsed houses or fallen furniture and provide first aid.

Necessary Household Supplies

It is a good idea to keep enough supplies that will support everyday living (food, etc.) for each person for three days after an earthquake. <Food> Rice, canned foods and other food that can be eaten with simple preparation (Keep an extra supply and use items according to their freshness dates). <Drinking Water and Everyday Living Water Supply> As a guideline, keep about three liters per person per day (Keep an extra supply of mineral water and use items according to their freshness dates). Keep water in your bathtub and washing machine in case you need a supply for everyday living and fire extinguishing. <Fuel> Tabletop stove (also need to keep a supply of gas casssettes), synthetic logs, charcoal, etc. <Other> Keep a flashlight (also need extra batteries) in case a disaster strikes at night. Keep regular medicine and first-aid items handy.

Emergency Backpack

It is a good idea to keep emergency items together so that you can easily palce them in a bag or backpack. <Valuables> Cash, savings account bankbooks, driver’s license, health insurance card, title deeds, etc. <Clothes> Underwear, outwear, shoes, towels, disposable diapers, rainwear, etc. <Emergency Food> Water, rice (includes processed foods), preserved foods such as biscuits, canned foods, retort/instant foods, etc. <Sundries> Radio, flashlight (extra batteries), candles, solid fuel, matches, lighters, paper cups, plates, knives, rope, newspapers, mats, towels, soap, sewing equipment, first-aid kit, regular medicines, etc.

Precautions for Earthquakes

Japan experiences unusually frequent earthquakes. It is always important to know what to do in the case of an earthquake, in order to reduce damage and injury caused by earthquakes to the minimum possible. Here are some basic guidelines to follow in preparing for earthquakes and dealing with their aftermath.

Advance Preparations

(1) Improve your home’s earthquake resilience Evaluate your home’s earthquake resilience, and improve it through steps such as fastening down furniture and putting anti-shatter coatings on glass windows. (2) Stockpile water and foodstuffs You should have at least three days’ worth of drinking water and foodstuffs stockpiled. You should also have radios and flashlights prepared. (3) Participate in disaster training Get to know the people in your community better by getting actively involved in community disaster training. (4) Discuss disaster preparedness with your family Verify how you will get in touch with each other and where the relief shelters are.

What To Do After an Earthquake

(1) The first two minutes after an earthquake • Protect yourself. Stay away from furniture that could topple over, and hide under a desk or table. Do not panic and run outside. (2) Immediately following an earthquake • Prevent fires and secure escape routes. Shut off gas valves and unplug electrical cords. If a fire breaks out, calmly begin to put it out. Secure escape routes by opening doors and windows. (3) The first three days following an earthquake • Make sure your family is safe, and watch out for aftershocks. Stay away from houses that have started to collapse. Call out to your neighbors, and depending on the situation, head for a shelter on foot. • Assist neighbors with firefighting, rescue, and relief. Cooperate with your neighbors to put out fires and rescue and attend to the injured. • Fend for yourself. Use the drinking water and food that you’ve stockpiled. Beware of false rumors and rely only on correct information. (4) From the fourth day onward Survival and Recovery Even after four days, you should watch out for aftershocks. Stay informed. Work towards getting things back to normal.

What To Do During an Earthquake

(1) Stop driving. • With a firm grip on the steering wheel, gradually reduce your speed, pull over to the left side of the road, and shut off the engine. • Until the tremors subside, calmly assess your surroundings and use your car radio to stay informed. • If you need to take shelter, leave your key in the ignition and the door unlocked. Taking your vehicle inspection papers and other important belongings with you, head for a shelter on foot.

(2) On the Road • Don’t just stand there. Use a bag or something else to protect your head from falling objects such as glass and building signs, and seek shelter in an open area or park. • Don’t get too close to cinder block walls or vending machines. • Watch out for telephone poles that are about to fall over and dangling power lines. • If there is no open space nearby, calmly assess your surroundings and move somewhere with a high degree of safety, away from buildings.

(3) Near the Shore • If you feel tremors, immediately seek the safety of high ground. Stay away from the shore until all tsunami alerts and warnings are lifted.

(4) On the Train • Grip the railing or hand strap tightly. • Even if the train stops between stations, do not exit the train on your own through a window or door using the emergency door override. • Calmly follow the instructions given to you by the conductors.

1. Earthquakes in Kyoto

In terms of large-scale earthquakes, it is expected that the many fault lines in Kyoto Prefecture, such as the Hanaore fault and Nara Basin Toen fault, will cause inland earthquakes. There is also a high probability of large damage occurring from a Tonankai-Nankai earthquake predicted to take place at sea.

2. Earthquake Countermeasures

(1) If you are at home First, move under a table or desk to protect your body. Calmly extinguish any fires, if possible. Protect children and the elderly. If the power supply is suspended due to the earthquake, switch off the circuit breaker. When the power is restored, check the safety of your appliances before you switch the circuit breaker back on.

(2) If you are in a department store Guard your head with your bag or a similar object and stand near a wall or pillar. Stay away from glass and display shelving. Evacuate according to the directions of those in charge.

(3) If you are on a train or bus The train or bus may stop suddenly. Hold on to a strap or rail. Follow the instructions of the crew.

(4) If you are in a built-up area Don’t stop moving, and guard your head with your bag or a similar object until you have reached a safe area. Don’t go near vending machines or the walls of buildings.

(5) If you are in a theater or hall Crouch down between the seats. Guard your head with your bag. Evacuate according to the directions of the ushers.

(6) If you are driving Slow down gradually and stop the car on the left-hand side of the road. If you exit your car, leave your key in the ignition and don’t lock the door.

(7) If there is a danger of a tsunami Stay away from the coast and rivers, and evacuate to higher ground as quickly as possible.

3. Earthquake Countermeasures in the Household

(1) Family Antidisaster Meeting Earthquakes occur suddenly. If you prepare for the worst, you will not regret it. You should hold a family meeting monthly, and discuss household antidisaster measures as well as responses and means to protect yourself in the event of an earthquake.

(2) Checklist for family antidisaster meeting • Make sure of each of your roles. • Consider the layout of your furniture and means to prevent it falling. • Ascertain the dangerous areas inside and outside of your house. • Check the use-by date of the items for emergency situations and replace them if necessary. • Confirm refuge points in the event of a disaster, for example, a school, park, etc. • Confirm points of contact in the event of a disaster, for example, distant relatives or the ’NTT 171 Dial.’ (3) Dangers inside the house Preventing objects from falling • Do not put too much weight on shelves/chests of drawers. • Put weighty objects for storage in lockers or bookshelves at a low level and light objects at a higher level. • Place furniture such as book shelves, cupboards, and chests of drawers in a position whereby they can be directly fixed to walls or pillars by using metal L-brackets, etc. Try to prevent things like television sets and computers from falling, by fixing them in place with adhesive tape, or tying them to posts or pillars with a belt, etc. Fire prevention • Periodically check the operation of the automatic extinguisher in heating appliances. • Regulate the area around heating appliances and use fire-resistant curtains to help prevent fires. Safety • Don’t put large pieces of furniture in bedrooms, children’s rooms or the rooms of the elderly. • To prevent the shattering of windows and cabinets place a layer of film over them.

4. Emergency Items

Category one items are to be taken with you in an evacuation as a result of an earthquake. As a rough standard, an adult male’s share is 15 kg, and an adult female’s share is 10 kg. The items should be dispersed across multiple rucksacks in case the family members should be separated. Category two items are for self-sufficiency until recovery from the earthquake is complete. The standard is the amount needed to last a family 3 days. Ascertain other necessary items according to particular family needs. Category one items • Valuables: cash, deed for house, bankbook, driving license, health insurance card, etc • Emergency provisions: canned food, mineral water • Medical articles: adhesive tape, salve, bandages, digestion medicine, analgesic, etc • Clothes: underwear, outer layers, towels, etc. • Radio, spare batteries • Lights: flashlight, candle, match, lighter, spare battery, etc. • Others: drugs, tampons, body warmer packs. If a baby is present: milk, diapers, etc. Category two items • Food: rice, canned goods, instant foods, spices, tableware, cooking utensils, can opener, bottle opener, etc. • Water: drinking water (3 liters per person per day, boiling required), water for living (bathing and washing) • Fuel: portable cooking stove, solid fuel, etc (enough gas stock is required for portable cooking stove)

5. Dangers outside house

• Fix propane gas cylinders with chains • Repair damaged block or stone walls.

• Block walls with no foundations (over 30 cm) or reinforcing bar are dangerous.

• Repair unstable antennas and tiles on roof. • Carefully arrange the placement of outdoor flowerpots so they are in a location with a minimal danger of falling.

6. Create a house resistant to earthquakes through reinforcements and repairs

How strong is your house against earthquakes? Carry out an analysis and strengthen it! (1) Strong Foundations Use foundations made with reinforced concrete fixed with bolts. (2) Repair of corroded parts Replace corroded parts and parts eaten by termites. (3) Attach metal fittings Strengthen joints such as foundations, poles, beams, etc, with metal fittings. (4) Strong walls Increase the strength of walls with plywood, increase the amount of walls, and check that they are well-balanced.

7. Local measures against earthquakes

When a large-scale earthquake occurs, municipal disaster prevention activities may not always run smoothly owing to bad conditions. Autonomous disaster prevention activities by local residents such as fire fighting, victim rescue, and evacuation are essential to prevent and reduce damage. Form an ’autonomous disaster prevention organization’ in your area to carry out disaster prevention training.

8. Ten points for your safety in the event of an earthquake

1. First, protect yourself Your life is the most important thing. When an earthquake occurs, protect yourself first. 2. Put out any fires and do not panic Put out any fires emanating from cooking and heating equipment with the assistance of other people. If you rush to put out cooking fires, implements may fall on you and cause injury. Wait for the shaking to stop before calmly extinguishing any flames. 3. Makes sure of your emergency exits In buildings made with reinforced concrete the building may become warped whilst the door is closed, and subsequently the door cannot be opened. 4. When fires occur, put them out immediately Put out fires at once in cooperation with your neighbors before they spread to the ceiling. 5. Stay calm if you escape outside If you escape outside, be cautious of falling tiles and glass and do not panic. 6. Don’t move towards narrow streets, walls, precipices and river banks. Be aware of objects that may fall easily such as block walls, gateposts or automatic vending machines. 7. Be cautious of landslides and tsunamis If you experience an earthquake in mountainous or coastal areas, evacuate immediately. 8. Evacuate on foot with minimum luggage Evacuate to refuge on foot. Don’t use cars or motorbikes. 9. Provide emergency aid in cooperation with others Help each other, including the aged people, the handicapped, the injured, etc. 10. Look out for reliable information Don’t get drawn in by groundless rumors, and obtain reliable information from radio and TV.