What to do during an earthquake? If you are indoors - duck or drop down to the floor. Take cover under a sturdy desk, table or other furniture. Hold on to it and be prepared to move with it. Hold the position until the ground stops shaking and it is safe to move. Stay clear of windows, fireplaces, woodstoves, and heavy furniture or appliances that may fall over. Stay inside to avoid being injured by falling glass or building parts. If you are in a crowded area, take cover where you are. Stay calm and encourage others to do likewise. If you are outside - get into the open, away from buildings and power lines. If you are driving - stop if it is safe, but stay inside your car. Stay away from bridges, overpasses and tunnels. Move your car as far out of the normal traffic pattern as possible. If possible, avoid stopping under trees, light posts, power lines, or signs. If you are in a mountainous area - or near unstable slopes or cliffs, be alert for falling rock and other debris that could be loosened by the earthquake. If you are at the beach - move quickly to higher ground or several hundred yards inland.

Earthquake Survival Kits

SURVIVAL SUPPLIES: Water-2 quarts to 1 gallon per person, per day. First Aid Kit-ample, and freshly stocked. First Aid Manual-know how to use it. Food-canned or individually packaged;precooked, requiring minimum heat and water. Consider infants, pets, and other special dietary requirements. Critical medication, extra eyeglasses Can opener Blankets Radio-portable battery operated, spare batteries Critical medication and eyeglasses, contact cases and supplies Fire Extinguisher-dry chemical, type ABC Flashlight-spare batteries and bulbs Watch or clock-battery or spring wound. COOKING: Barbeque-use outdoors ONLY-charcoal and lighter, or Sterno stove Plastic bags-various sizes, sealable Pots-at least two Paper plates, plastic utensils, and paper towels SANITATION Large plastic trash bags-for trash, waste, water protection Ground cloth Large trash cans Hand soap, liquid detergent, shampoo Toothpaste, toothbrushes, dental floss Deodorant Feminine supplies Infant supplies Toilet paper Powdered chlorinated lime-to add to sewage to disinfect and keep away insects. Newspapers-to wrap waste, garbage; may also be used for warmth. SAFETY Heavy shoes for every family member Heavy gloves for every person cleaning debris Candles Matches-dipped in wax and kept in waterproof container Knife-sharp, or razor blades Garden hose-for siphoning and fire fighting Clothes-complete change kept dry TOOLS Axe Shovel Broom Crescent wrench-for turning off gas main Screwdrivers Pliers Hammer Rope or bailing wire Plastic tape Pen and paper Mini Survival Kit for Automobile Non-perishable food-store in coffee cans Boiled water First aid kit and manual Fire extinguisher Blanket Sealable plastic bags Flashlight-spare fresh batteries and bulb Critical medication, extra eyeglasses Tools-screwdriver, pliers, wire, knife Short rubber hose Pre-moistened towelettes Feminine supplies Sturdy shoes and gloves

Your emergency supplies should be adequate for at least 72 hours (3 days). A 10-day supply of water, food, and medicine is recommended !

Earthquake prediction

An earthquake prediction is a prediction that an earthquake in a specific magnitude range will occur in a specific region and time window.

An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. Earthquakes are recorded with a seismometer, also known as a seismograph. The moment magnitude of an earthquake is conventionally reported, or the related and mostly obsolete Richter magnitude, with magnitude 3 or lower earthquakes being mostly imperceptible and magnitude 7 causing serious damage over large areas. Intensity of shaking is measured on the modified Mercalli scale.

At the Earth's surface, earthquakes manifest themselves by a shaking and sometimes displacement of the ground. When a large earthquake epicenter is located offshore, the seabed sometimes suffers sufficient displacement to cause a tsunami. The shaking in earthquakes can also trigger landslides and occasionally volcanic activity.

In its most generic sense, the word earthquake is used to describe any seismic event—whether a natural phenomenon or an event caused by humans—that generates seismic waves. Earthquakes are caused mostly by rupture of geological faults, but also by volcanic activity, landslides, mine blasts, and nuclear experiments.

An earthquake's point of initial rupture is called its focus or hypocenter. The term epicenter means the point at ground level directly above this.

The majority of tectonic earthquakes originate at depths not exceeding tens of kilometers. In subduction zones, where older and colder oceanic crust descends beneath another tectonic plate, Deep focus earthquakes may occur at much greater depths (up to seven hundred kilometers). These seismically active areas of subduction are known as Wadati-Benioff zones. These are earthquakes that occur at a depth at which 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.

Earthquakes also often occur in volcanic regions and are caused there, both by tectonic faults and by the movement of magma in volcanoes. Such earthquakes can serve as an early warning of volcanic eruptions.

Sometimes a series of earthquakes occur in a sort of 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, and 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, the half dozen large earthquakes in New Madrid in 1811-1812, and has been inferred for older anomalous clusters of large earthquakes in the Middle East and in the Mojave Desert.

Effects/impacts of earthquakes

There are many effects of earthquakes including, but 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 or other rigid structures. The severity of the local effects depends on the complex combination of the earthquake magnitude, the distance from epicenter, and the local geological and geomorphological conditions, which may amplify or reduce wave propagation. 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 to effects of seismic energy focalization

owing to typical geometrical setting of the 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 few metres 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 likely to break the ground surface within the life of the structure.

Landslides and avalanches

Earthquakes can cause landslides and avalanches, which may cause damage in hilly and mountainous areas.

Fires

Following an earthquake, fires can be generated by break of the 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.

Soil liquefaction

Soil liquefaction occurs when, because of the shaking, water-saturated granular material temporarily loses its strength and transforms from a solid to a liquid. Soil liquefaction may cause rigid structures, as buildings or bridges, to tilt or sink into the liquefied deposits.

Tsunami

Undersea earthquakes and earthquake-triggered landslides into the sea, can cause

Tsunami. See, for example, the 2004 Indian Ocean earthquake.

Human impacts

Earthquakes may result in disease, lack of basic necessities, loss of life, higher insurance premiums, general property damage, road and bridge damage, and collapse of buildings or destabilization of the base of buildings which may lead to collapse in future earthquakes.

Controversy in trying to predict earthquakes

In the effort to predict earthquakes, people have tried to associate an impending earthquake

with such varied phenomenon as seismicity patterns,

 electromagnetic fields, weather conditions and unusual clouds, radon or hydrogen gas content of soil or ground water, water level in wells, animal behavior.

Thus far, earthquake prediction is controversial because data are sparse and there is little evidence or verified physical theory to link observable phenomena to subsequent seismicity. The frequent practice of polishing predictions after the fact further complicates matters. Also, given enough predictions, it is virtually inevitable that some will succeed "by chance." Assessing whether a successful prediction is a fluke is challenging. Most assessments rely on chance models for earthquake occurrence, models that are difficult to test or validate, because large earthquakes are so rare, and because earthquake activity is naturally clustered in space and time.

Size and frequency of occurrence

Small earthquakes occur nearly constantly around the world in places like California and Alaska in the U.S., as well as in Chile, Peru, Indonesia, Iran, the Azores in Portugal, New Zealand, Greece and Japan.Large earthquakes occur less frequently, the relationship being exponential; for example, roughly ten times as many earthquakes larger than magnitude 4 occur in a particular time period than earthquakes larger than magnitude 5. 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
• an earthquake of 5.6 or larger every 100 years.

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 because of the vast improvement in instrumentation (not because the number of earthquakes has increased). The 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.In fact, in recent years, the number of major earthquakes per year has actually decreased, although this is likely a statistical fluctuation. More detailed statistics on the size and frequency of earthquakes is available from the USGS.

Most of the world's earthquakes (90%, and 81% of the largest) take place in the 40,000-km-long, horseshoe-shaped zone called the circum-Pacific seismic belt, also known as the Pacific Ring of Fire, which for the most part bounds the Pacific Plate. Massive earthquakes tend to occur along other plate boundaries, too, such as along the Himalayan Mountains.

With the rapid growth of mega-cities such as Mexico City, Tokyo or Tehran, in areas of high seismic risk, some seismologists are warning that a single quake may claim the lives of up to 3 million people.