Earthquakes Geologists today define an earthquake as the shaking and the trembling of the earth’s surface, known as the ground. Earthquakes are caused by the sudden release of energy, usually as a result of faulting which involves displacements of rocks along fraction. All of this energy has been building up for a long period of time and then suddenly just blows. Most earthquakes result from energy being released along plate boundaries and as such “earthquakes are manifestation of earth’s dynamic nature to the fact that earth is an internally active planet” (Hough). After an earthquake’s continuing adjustments along a fault may then generate a series of earthquakes. These certain earthquakes are known as aftershocks. Aftershocks can be as large, destructive and damaging as the first original earthquake that happened or it can be less destructive to not even knowing that this has occurred. An earthquake is one of nature’s most frightening as well as most destructive circumstances on the planet earth. The earthquakes are also most frightening when it first begins. This is due to the fact of the unknown. You have no idea how long the earthquake will occur or how violent it will be. Earthquake’s can be very destructive in many ways. “Collapsing buildings claim by far the majority of lives, but the destruction is often compounded by mud slides, fires, floods, or tsunamis”(National Geographic par.3). They can kill one person up to one hundred thousand people. Loss of life can be avoided through emergency planning, education, and the construction of buildings that sway rather than break under the stress of an earthquake. More than 900,000 earthquakes occur per year, with more than 31,000 of those strong enough to be felt. Earthquakes... ... middle of paper ... ...riving when one hits move your car out of traffic and stop driving, and get in an open space. After all the devastating destruction is over there are a few things you should check for. Check for fire or fire hazards, also check for the smell of gas, and shut off all electricity. And most important fall back to your layout plans that you made before, go to your safe place and stay there. Like I said before your supplies and what you need will vary on where you live and how often earthquakes occur in your location. Of course living here in Georgia we might not need all the food supplies and other things, but we should know what to do during an earthquake. Knowing all of this information about earthquakes can help save lives. This can make people aware of how earthquakes happen, what effects they have when they happen, how to prepare and what to do at the end result.
Earthquakes, by Webster’s dictionary definition, are, “a shaking or trembling of the earth that is volcanic or tectonic in origin.” World Book Encyclopedia reports scientists believe that more than 8,000 earthquakes occur each day without causing damage. A little more than 1,000 each year are strong enough to be felt. Earthquakes occur in the general sense, anywhere on land. Other earthquakes go by different names, such as volcanic eruptions and tsunamis, large tidal wave storms that occur underwater, primarily in the Pacific Ocean.
Earthquakes play a major role into understanding the composition and materials that exist within the Earth (Merali and Skinner, 2009, p.252). Earthquakes are the main source of insight into the inner workings of the earth, due to the nature of the seismic waves they produce. P and S waves are reflected and refracted at different boundaries within the earth, and this enables seismologists to make inferences about the internal composition and structural of planet Earth. (Merali and Skinner, 2009, p.252).
The earth is split into four layers, inner and outer core, the mantle and crust. The top of the mantle and crust make up what is like the skin of our earth (see source 2). The skin is split up like a puzzle and we call these puzzle pieces’ tectonic plates (see source 1). These plates are constantly moving and the plate boundaries (edges of the plates) move and slide past one another. Sometimes as the plates move the plate boundaries become stuck. Pressure builds up in the stuck area over time and eventually breaks. This is why earthquakes occur due to the sudden movement of the plate sliding and breaking creating a fault line to go off. The fault line is the line on which the
Earthquakes in California are certainly not a surprise. What is a surprise is their unpredictability and randomness. Geologists say there is roughly a 50 percent chance that a magnitude 8 or more quake will hit the Los Angeles area sometime over the next 30 years. And, over the past twenty years, the Los Angeles area has witnessed several earthquakes, and in particular, two that were quite devastating; the 1971 San Fernando earthquake, and the January 17, 1994, Northridge Earthquake. Given the certainty that earthquakes will occur, they still seem to come as a surprise, and leave many communities unprepared to deal with their aftermath.
An earthquake is the shaking of the ground caused by sudden release of energy inside the earth's crust. It's the breaking and moving of tectonic plates along a fault line. Earthquakes can range in size from weak where we don't feel them to extremely violent where they actually thow people around and destroy cities. They may be a result of geological faults or other activites such as volcanoes, landslides, mine blasts and nuclear tests. An earthquake is not always naturally caused.
Since record keeping began, sometime in the 18th century, there have been 13 major earthquakes along the San Andreas Fault. However, radiocarbon dating has proved that earthquakes have been happening along the fault for thousands of years. The earliest recorded earthquake happened on July 28, 1769, and was experienced by Spanish explorer Gaspar de Portola while he camped along a small lake he named “San Andreas Lake”. Other notable early earthquakes occurred in 1836, 1838, 1865, 1868, and 1890. Unfortunately, there is no seismographic data recorded for these early earthquakes since it was not until 1887 that seismographs began being used in the United
One of the worst natural disasters in United States history to this date occurred almost 109 years ago. On April 18, 1906 at 5:15am in San Francisco, California, the earthquake of San Francisco occurred hitting between 7.9 and 8.3M on the Richter scale. The San Andreas Fault, which is about 600 miles long, running from the Gulf of California to Cape Mendocino and is an active strike-slip fault, cut through the continental lithosphere to cause the San Francisco Earthquake of 1906. An earthquake is a trembling or shaking of the ground produced by movements along a fault (Strahler, 2012). After the tension is released at a critical point, the fault or tectonic plate slips and relieves the strain and creates the seismic waves, which radiates out in all directions causing the shaking of the surface.
D.J. Dowrick (”Earthquake Risk Reduction”in Wiley) explains that seismic hazard is any physical phenomenon associated with an earthquake that may produce adverse effects on human activities. Earthquakes occur very suddenly without any warning. Thus, earthquake not only destructs people’s living environment, but also affects people’s mental health. People are more scared of earthquake. In 2010, there are two severe earthquakes, which are Haiti Earthquake and Chile Earthquake. Both of these two earthquakes produced the various impact considerably across countries and regions. The purpose of this essay is to analyse those two earthquakes according to knowledge such as why they occur, how strong they are, and what the impact they made. Even though people still can not predict earthquake, through analyse earthquakes, they can prevent it bring huge losses.
Earthquakes are best described as a shaking or vibration of the ground caused by breaking of rock. Sometimes they are very strong and other times you would hardly notice them. This shaking occurs when stress that builds up in the crust is suddenly released as the crust breaks free and/or slides against the other pieces of crust. Earthquakes may also be thought of as the breaking of a popsicle stick by applying pressure to both ends at the same time. Should you try this experiment , you will feel the pressure build up as you apply more force until the stick snaps. When the stick snaps you will feel an instant of pain at your fingers as the stress reduces and energy waves move throughout the stick. When the earth's crust is placed under similar types of stress, binding as the stress builds, it will also snap and release the energy into the surrounding rocks, 'ooch'. Thinking about earthquakes will become more clear if you try another experiment.
Problem Statement: Earthquakes are a natual part of the environment. They do,however,cause devistating effect on the environment. Since Earthquakes can not be avoided, maybe there is a way to determine when they are going to occur so precautions can be taken to get people to safety and protect as much of
Hazards pose risk to everyone. Our acceptance of the risks associated with hazards dictates where and how we live. As humans, we accept a certain amount of risk when choosing to live our daily lives. From time to time, a hazard becomes an emergent situation. Tornadoes in the Midwest, hurricanes along the Gulf Coast or earthquakes in California are all hazards that residents in those regions accept and live with. This paper will examine one hazard that caused a disaster requiring a response from emergency management personnel. Specifically, the hazard more closely examined here is an earthquake. With the recent twenty year anniversary covered by many media outlets, the January 17, 1994, Northridge, California earthquake to date is the most expensive earthquake in American history.
The 1994 Northridge earthquake was a disaster, as it “involved an entire community” (Edwards, 2013). The earthquake resulted in extensive damage to the infrastructure of the community and localized, long term, multidimensional negative effects to the surrounding communities (Edwards, 2013). While the earthquake had many characteristics of a catastrophe, it did not include “significant damage to the disaster response assets and deaths or injuries to emergency response personnel” (Edwards, 2013). The earthquake required assets from outside the community, such as Caltrans and the FHWA. Also, the damage and disruption was “confined to a sufficiently narrow geographic area” (Edwards, 2013).
Earth has few layers and one of them is the lithosphere. It is broken down to tectonic plates and sometimes these plates slide inside the earth. This activity causes the earthquakes.Earthquake waves are also known as Seismic waves and they can be measured using a seismometer. The measurement gives an earthquake a number on the Richter scale. The largest earthquake ever recorded was in Chile in 1960, and registered a 9.5 on the Richter scale.
Earthquakes are vibrations felt at the surface of the earth which are caused by disturbances of the energy in the earth's interior. These vibrations are known as seismic waves. (Skinner Robinson McVerry 1) There are different type sof seisimc waves such as Primary (P) waves, whcih travel the fastest, Secondary (S) waves which cause the earth to vibrate vertically, Surface (L) waves. P and S waves are "affected by changes in the density and the rigidity of the materials through which they pass." (Columbia Encyclopedia) Earthquakes vary in their intensity and duration. Often times they are strong enough to cause massive destriction. Tall buildings often suffer as a result of these natural disasters. In recent years this has become a larger and larger threat with both the number of large buildings, and their number of occupants increasing. In an effort to try to minimize the damage caused by earthquakes many some engineers focus primarily on designing and constructing earthquake resistant buildings. Earthquake engineers have gathered much of their information from analyzing past earthquakes, and learning which buildings can and can't withstand the tremors. The goals of these engineers is to design buildings that can withstand moderate earthquakes and obtain minimal damage, and that the buildings will not collapse lowering the probability of human deaths.
Earthquakes belong to the class of most disastrous natural hazards. They result in unexpected and tremendous earth movements. These movements results from dissemination of an enormous amount of intense energy in form of seismic waves which are detected by use of seismograms. The impact of earthquakes leaves behind several landmarks including: destruction of property, extensive disruption of services like sewer and water lines, loss of life, and causes instability in both economic and social components of the affected nation (Webcache 2).