...An earthquake is defined as a sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth's crust or volcanic action by the dictionary. Earthquakes happen frequently, but most people only hear about the ones that cause much damage and fatalities in the news. Some earthquakes have a high magnitude with less damage than other earthquakes that have a lower magnitude with more damage and fatalities. There are several explanations to this. The Haitian earthquake on Tuesday January 12, 2010 had a magnitude of 7.0 and a depth of 13km. This earthquake resulted in 316,000 people dead, 300,000 people injured, and 1.3 million people displaced. Tsunami waves were reported in multiple locations including Santo Domingo and the Dominican Republic. The earthquake occurred in the region separating the Caribbean plate and the North American plate. The earthquake was caused by a transform fault which is a strike-slip fault occurring at the boundary between two plates of the earth's crust. After the initial earthquake, fifty-nine aftershocks of 4.5 or greater were felt. Damages and fatalities were high because of the magnitude and the lack of building regulations to withstand earthquakes. Haiti,...
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...Earthquake From Wikipedia, the free encyclopedia This article is about the natural seismic phenomenon. For other uses, see Earthquake (disambiguation). [pic] An earthquake (also known as a quake, tremor, temblor or seismic activity) is the result of a sudden release of energy in theEarth's crust that creates seismic waves. Earthquakes are measured with a seismometer; a device which also records is known as aseismograph. The moment magnitude (or the related and mostly obsolete Richter magnitude) of an earthquake is conventionally reported, with magnitude 3 or lower earthquakes being mostly imperceptible and magnitude 7 causing serious damage over large areas. Intensity of shaking is measured on the modified Mercalli scale. At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacing the ground. When a large earthquakeepicenter 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 orhypocenter. The term epicenter refers to the point at...
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...WHAT IS EARTHQUAKE? Earthquakes are the vibrations caused by rocks breaking under stress. The underground surface along which the rock breaks and moves is called a fault plane. Earthquakes in Australia are usually caused by movements along faults as a result of compression in the Earth’s crust. The size or magnitude of earthquakes is determined by measuring the amplitude of the seismic waves recorded on a seismograph and the distance of the seismograph from the earthquake. These are put into a formula which converts them to a magnitude, which is a measure of the energy released by the earthquake. For every unit increase in magnitude, there is roughly a thirty-fold increase in the energy released. For instance, a magnitude 6.0 earthquake releases approximately 30 times more energy than a magnitude 5.0 earthquake, while a magnitude 7.0 earthquake releases approximately 900 times (30x30) more energy than a magnitude 5.0. A magnitude 8.6 earthquake releases energy equivalent to about 10 000 atomic bombs of the type developed in World War II. Fortunately, smaller earthquakes occur much more frequently than large ones and most cause little or no damage. Earthquake magnitude was traditionally measured on the Richter scale. It is often now calculated from seismic moment, which is proportional to the fault area multiplied by the average displacement on the fault. The focus of an earthquake is the point where it originated within the Earth. The earthquake epicentre is the point on...
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...population). This can vary between countries. Also, a disaster is something which causes very distressing or ruinous effects which disrupt functions of an organisation, society or system. What constitutes a disaster is the societies inability to cope rather than the event itself. There are a number of things besides poverty that can accentuate the effects of an earthquake such as the structure of the buildings, the population density, the education of the people but also more physical factors such as magnitude and the time of day when the earthquake hits. Poverty by itself can completely change the effects that the earthquake can have. If the money isn’t available to pay for preparation, monitoring, education about such problems and recovery, then does a country really have a chance against a natural event such as an earthquake? An example of the difference between the amount of money that countries have, is Bam which is located in Iran on the Arabian, Eurasian and Indo-Australian plates and California on two plates that run parallel to the San Andreas Fault. These two earthquakes were very similar for example the Sam Simeon earthquake which hit California occurred on 22nd...
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...What is EARTHQUAKE ? 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 createsseismic 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 March 2014), 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...
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...amounts. This essay will focus on the major, most famous tsunamis in the world’s history. Tsunamis occur mostly in the Pacific Ocean mostly around the Ring of Fire (“Tsunamis”). This is because this dangerous area is known for its production of such disasters as volcanic eruptions, earthquakes, or even both trigger the Tsunami. There have been spectacular tsunamis in the past. 1707 Hoei Tsunami was for centuries the largest earthquake in Japan (“1707 Hōei earthquake”). The earthquake that caused it had magnitude of 8.6. The earthquake’s fault rupture extended to more than 700 km (“Abstract”). Back in 1771, an earthquake of a 7.4 magnitude occurred just south of the Okinawa, Japan Island. Killing nearly eight and a half thousand people, a tsunami of mass destruction took place. The population decrease to about one third and more than 2,000 houses were demolished (“1771 Great Yaeyama Tsunami”). Comparatively, on November 1, 1775 an earthquake in the Kingdom of Portugal occurred. The earthquake caused fires and a tsunami. This tsunami almost completely destroyed Lisbon, in the Kingdom of Portugal. The Lisbon earthquake had a magnitude of 8.7 on the moment magnitude scale (“1775 Lisbon earthquake”). In 1792, Japan was again caught in a horrendous natural disaster. They faced what is called their most deadly volcanic eruption ever. The Mount Unzen volcano caused this tsunami. It caused a tsunami that killed approximately 15,000 people with waves that reached up to 330 feet (“1792...
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...“Earthquake Danger in the Midwest” Kaplan University SC300-13 July 1, 2011 The United States Geological Society (2011) states “The world’s earthquakes are not randomly distributed over the earth’s surface, and tend to be concentrated in narrow zones”. This statement seems to hold true when it comes to the distribution of earthquakes in the United States as they happen primarily in those narrow fault zones. These fault zones are located in Alaska (Prince William Sound), on our West Coast ( San Andreas Fault), on our East Coast (Rambo Fault Line) and in the Midwest (New Madrid Fault) which all lying on the North American Tectonic Plate, a massive irregularly shaped slab of solid rock which is approximately 8000 kilometers or almost 5000 miles wide (Trefil and Hazen, 2011). Tectonic plates are in constant motion as they interact along their margins to form mountain belts, earthquakes and volcanoes. Plate size can vary greatly, from a few hundred to thousands of kilometers across; the Pacific and Antarctic Plates are among the largest. Living in Cincinnati, Ohio carries a relatively high risk of a major earthquake because it lies on the border of the New Madrid Seismic Zone (NMSZ) and the Wabash Valley Seismic Zone (WVSZ) which have the most active geological areas in the eastern United States. The smaller of the two areas is the Wabash Valley area which lies in the Southeastern part of Illinois and Southwestern part of Indiana and came...
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...Adrian Howley Classical Argument Reporting earthquakes are very critical to studying the behavior of tectonic plates. The very first recorded earthquake occurred in the year 1831 B.C. and is currently known today as the 526 Antioch Earthquake. The area affected was Antioch, China (located between the Syria and Turkey regions). Not much is known about how the report was formed. However, this historic report did include information about how the aftershocks lasted for twelve months. Other details from this report indicate that the death toll is around 250,000 to 300,000 casualties. Scientists today can only prove that the earthquake occurred between May 20 and May 29 (date translated from B.C. to Calendar Year). The first instrument to measure the seismic waves of earthquakes was invented by Charles F. Richter at the California Institute of Technology. (Bellis, 2013) He introduced his new instrument called the Richter scale, to the world of science. His invention allows scientists today to study the mechanics behind earthquakes and locate the epicenter to which the natural disaster originated. The largest earthquake recorded by the Richter scale was measured on May 22, 1960 at a magnitude of 9.5. The quake resulted in 1,886 deaths, 2,000,000 homeless, and $1,175,000,000 total in damages. (“The Largest Earthquake”, [PDF file]) If we want to see these large numbers slide down to zero, the impossible will need to be challenged by science. Skyscrapers are buildings consisting...
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...EARTHQUAKES IN 2013 Numerous earthquakes also rocked the world in 2013. Some of the most intense of these events include: a 7.7 magnitude temblor in Pakistan in September; a 7.1 magnitude quake in the Philippines in October; 6.4 and 7.7 magnitude events in Iran last April; and in China, a 6.6 magnitude quake in April and an M5.9 tremor in July. The largest deep earthquake ever recorded struck in May under the Sea of Okhotsk in the northwest Pacific Ocean. It measured an 8.3 magnitude at 378 miles below the surface. No notable damage was caused but the vibrations were felt over a wide area, including Moscow, Russia, which was 5,000 miles west of the occurrence. While some of the most potent temblors occurred over the rest of the world, the US also had its fair share of shaking. In January, a 7.5 magnitude earthquake was felt off the west coast of southeastern Alaska; in August, a 7.0 magnitude occurred in the Aleutian Islands of Alaska — several other quakes were felt around the world within the same time period as the Aleutians’ temblor; in March, a 4.7 magnitude quake rocked Arizona; and in May, a 5.7 magnitude event hit the Canyondam area. Earthquakes weren’t the only things shaking the ground in 2013. Other events detailed in the USGS report that rocked the earth include a fertilizer plant explosion in West, Texas, in April. It generated a 2.1 magnitude tremor that was felt in 36 different zip codes. The Chelyabinsk meteor explosion in Russia in February caused...
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...Comparing 2 different Earthquake Cases Introduction: In this essay I will be comparing 2 different cases of Earthquakes, 1 in an MEDC (More Economically Developed Country) and the other in an LEDC (Less Economically Developed Country) both of a magnitude of 7.0. The two earthquakes that I will be comparing are the Kobe Earthquake in Japan in 1995 of a magnitude of 7 (for the MEDC) and the Haiti Earthquake in 2010 of a magnitude of 7.0 (for the LEDC).I will be comparing the impact after the Earthquake, the damage inflicted on the city, the cost in damage and the loss of lives and the amount of injuries. I will be doing this to see how the economic bracket and earthquake proof buildings can affect the damage inflicted onto the cities affected...
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...Prof: Tanya Crail What’s a earthquake? According to the Geology Labs on-line website an earthquake is the sudden release of stored energy, caused by the shifting of tectonic plates. The energy release is a shock wave or seismic wave. The seismic wave is what causes the ground to move or shake, when this occurs we have a earthquake. According to the 2008 United States National Seismic Hazard Maps a lot of the west coast as far south as Hawaii, and north to Alaska has a lot of earthquake activity. The Pacific “Ring of Fire” (named for the large amount of active volcanoes), has a lot of tectonic activity. Tectonic plates are large plates of rock that make up the foundation of the Earth's crust and the shape of the continents. Question: What patterns do you see in the distribution of earthquakes across the continental United States? Answer: Earthquakes occur on fault lines, a location where tectonic plates have collided together and shifted or are sliding past each other. The size of the earthquake depends on how much slide or shift occurred. Most fault lines are located in costal areas, because of the continental and oceanic plates colliding together. Most of the United States earthquakes occurs on the west coast. California, and the entire west coast including Hawaii, and Alaska have the highest hazard rating at 64+, central locations of the United States like Texas, North and South Dakota seem to have the lowest risk of earthquakes, however Missouri, Illinois, Indiana...
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...Earthquakes Michael R. Rice PSHC 210 11/17/12 Unpreventable and potentially devastating, earthquakes offer geologists insight into the Earth's structure. Even though scientists cannot stop an earthquake from happening they are developing a better understanding of how and why earthquakes occur. Studying where, how, and why the earth shakes can give people more knowledge into preparing for and recovering from earthquake disasters. Although scientists cannot predict short-term forecasting with any true accuracy, they can determine which areas are at risk of experiencing a substantial earthquake through long-term forecasting (Murck, Skinner, & Mackenzie, 2008). Earthquakes are a result of two tectonic plates moving past one another. Because the plates do not slide past each other smoothly often the edges of the plates, or plate boundaries, stick together whereas the rest of the block continues to move (Wald, 2009). The plate boundaries are comprised of numerous faults, and it is along the faults where the majority of earthquakes occur (Murck, Skinner, & Mackenzie, 2008). The energy that normally forces the plates to the move past one another begins to store until the power of the parts of the plates still in motion overcome the friction caused by the parts that are stuck and release the plate (Wald, 2009). The result is a release of the stored energy that then radiates as seismic waves in all directions (Murck, Skinner, & Mackenzie, 2008). The amount of...
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...in the distribution of earthquakes across the continental United States? Most earthquakes occur in the United States along the coast of the Pacific, particularly the shoreline of California, Alaska and Japan in addition to earthquakes that occur in the mid-west and east coast states and along the border amid Kentucky, Missouri, Arkansas and Tennessee. As noted, the highest levels of risk are in the west coast whereas the eastern central region is more moderate risk and insignificant risks are among northern and southern regions. Locate your home on this map and make a note of the relative risk to you by indicating the color where you live. Chicago, Illinois – has a very low hazard of occurrence. Magnitude: 2.5; Region: Mid-West. According to Earthquakes (2012), Illinois is at risk from two major seismic zones, the Wabash Valley Seismic Zone and the New Madrid Seismic Zone (NMSZ). The Wabash Valley Zone is located between southeastern Illinois and southwestern Indiana. The NMSZ is located in the Central Mississippi Valley and includes portions of the states of Alabama, Arkansas, Illinois, Indiana, Kentucky, Missouri, Mississippi, and Tennessee. During any 50-year time span, there is a 25% to 40% chance of a magnitude 6.0 or greater earthquake in this seismic zone. Since 1974, the year network monitoring of seismic activity began, more than 3000 earthquakes have been recorded in the NMSZ. Fortunately, none of these earthquakes exceeded a magnitude of 5.0, and most occurred...
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...CHAPTER 2 Review of Related Literature 2.1 Foreign Literatures 2.1.1 The Simplified Method The Simplified Method is the most common procedure for evaluating the liquefaction potential of soil. Developed by H.B. Seed and I.M. Idriss in 1971, this method uses two fundamental terms: (1) Cyclic Stress Ratio (CSR), and (2) Cyclic Resistance Ratio (CSR). The CRR characterizes the liquefaction resistance of granular soils and is typically acquired from in situ tests. It can also be estimated by cyclic tests on reconstituted soil samples. According to a summary report by Youd and Idriss (2001), the 1996 NCEER and 1998 NCEER/ NSF Workshops reviewed the modern method of analysing the potential liquefiable layers of soil. They recommended revised criteria for routine evaluation of CRR from various tests such as the Cone Penetration Test (CPT) and the Standard Penetration Test (SPT). Robertson and Wride (1998) informed that CRR evaluated by CPT may be adequate for low-risk, small-scale projects. But for medium to high-risk projects, there may be more than one method that should be used to determine the CRR. Idriss and Boulanger (2004) commented that the quality of the site characterization is the greatest factor that could affect any liquefaction evaluation. The workshops concluded that it might be much more specific when two or more tests should be used for a more reliable value of CRR. As for the evaluation of CRR from laboratory tests, the chief hindrance is the acquiring of in...
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...Fronabarger PLATE TECTONICS AND EARTHQUAKE HAZARDS IN LOS ANGELES There are many serious hazards associated with earthquakes in the Los Angeles metropolitan area. This includes ground shaking, ground displacement, liquefaction, fires, and tsunamis (Girty, 2009, Chapter 7). During an earthquake there are varying degrees of vibration of the ground, dependent on the magnitude of the earthquake. This violent movement of the soil can compromise the structure of buildings or other structures made by man, causing them to crumble to the ground and crushing anything, or anyone, that may be in close proximity. If some sort of structure, made by man or by nature, happens to lie upon a fault line, the ground displacement of the foundation of the structure can also cause immense damage by ripping apart the land. In some instances, where soil is highly saturated, such as coastal areas or low elevation, liquefaction is another hazard. When the ground shakes, any present liquid will rise up through the soil and make sinkhole conditions where structures can sink right into the ground. With this kind of destruction, comes the hazard of fires as well. During a violent earthquake, electrical and gas lines can be destroyed and exposed to ignition sources that can ignite and cause fires that may be inaccessible and be extremely destructive. Lastly, tsunamis are a risk to L.A. when there are quakes offshore that launch large quantities of sea water over the coastal land. Earthquakes are a result of a large...
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