The Physical and Human Factors Which Affect the Location and the Impact of the Earthquake Hazard
Earthquakes are natural hazards that have occurred since the dawn of
time. They are products of the Earth's ever-changing face and lead to
the movement of the world's tectonic plates. An earthquake is a hazard
resulting from major geological processes and the release of energy
within the earth leading to catastrophic incidents such as earthquake
and volcanic eruptions. The effects of earthquakes can have
considerable damage to the physical and human environments and the
impact and location of an earthquake can alter the damage of the
process.
Earthquakes are most likely to occur at the boundaries of the
lithospheric plates. They occur from movements along fractures in
rocks called faults. Movements occur along the faults because of the
stress put upon the area due to crystal movement, the stress is not
released gradually but it builds up and becomes so great until the
rocks are forced to shift suddenly along the fault. Once the fault
moves the shock waves produced results into an earthquake, the point
of break is called the focus.
The physical factors that effect the location and impact of the
earthquake can have a large impact upon the hazards the process
causes. The location of the earthquake is most likely to occur at
plate margins thus if a settlement is located alongside these plate
margins it is more likely that they are going to receive earthquakes
than settlements not located upon the plate margins. The city of San
Francisco located above the San Andreas Fault is one of the most
earthquake prone cities in the world and receives small earthquakes
everyday. The location of the focus is also very decisive when
considering the impact that the earthquake might yield, if the focus
is located far below ground then the shock waves will be absorbed by
the ground and the impact that the earthquake will have will be
minimal. But if the focus is located several meters below ground such
as during the Loma Prieta earthquake in 1989 then the impact will be
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
New Madrid earthquake of 1811-1812 was known to be “one of the most powerful earthquake felt throughout the Eastern United State”(2,75) . “December 16, 1811 at 2 a.m”(1). , the first earthquake had struck in the Northern part of Arkansas through Missouri. “This earthquake occurred in Central Mississippi Valley”(2,2) . New Madrid fault is located in the northern part of Missouri and southern part of Illinois. On the morning of December 16, 1811, when the earthquake struck; “people were scared”(10,26) , they ran out of their houses as the trees were falling onto the ground and the ground was breaking up. After the earthquake ended, around 7 a.m., one of the largest aftershock occurred and it was known to be a destructive shock because
Earthquakes have been recorded throughout history for thousands of years. Even before seismographs in early times, there are records and accounts of mysterious ground shaking. Earthquakes occur when rocks break along an underground fault (UPSeis, 2007). This, in return, causes vibrations through the earth which causes ground shaking. The magnitude of the shaking varies depending on how great the movement along the fault is; the greater the movement, the bigger the earthquake. Some earthquakes are huge and cause significant damage, while others are small and cause little or no damage what-so-ever. Earthquakes are unpredictable, and can happen at any time. It is uncertain where an earthquake will strike, but there is a greater risk of an earthquake for areas lying on or near a fault. No one is ever prepared for an earthquake, so the people affected must face a sometimes terrifying reality and can be scarred for life. One country in particular that has been severely affected from an earthquake is Italy. Over a century ago Messina, a city located in Sicily, was to face one of the most devastating natural events of the century.
Due to the hazard that earthquakes cause, a hazard consultant becomes a critical part of
The dangerousness of earthquakes are rated from one to ten. One being you aren’t able to feel it and ten being VERY powerful. There was a deadly earthquake, almost no one survived. A deadly 7.2 earthquake occurred in the Central Philippines. All signs and clues pointed to the East Bohol Fault. A 6 rated earthquake that happened before, injured 300 people and caused a tsunami. But the 7.2 earthquake didn’t cause any tsunami. All of the dangerous earthquakes damaged ports, schools and airports; even a hospital collapsed killing at least 18 people. Children were injured in stampedes at two sports complexes while others rushed to the exits. Five people were killed in a earthquake - triggered landslide. People respond to a natural disaster by gathering resources, spreading the word, and government help.
Mr. Adams describes the San Francisco earthquake as his most profound human suffering experience because the horror of shaking floors, parts of his mom’s house collapse to the floor, and got a broken nose from stumbling into a brick wall (Ansel Adams & The 1906 Earthquake 2008). Earthquakes are part of natural disasters of the earth and normally caused by shaking ground and rapid movement of one block of rock slipping past another a long fractures in the earth crust called faults. Faults that are usually locked excluding abrupt movements, which slippage creates an earthquake (Lutgens, F. & Tarbuck, E.
Fire extinguisher. Check. Working flashlight. Check. Canned food. Check. These emergency necessities were part of the apartment supplies during one of the most traumatizing, memorable, and scary part of my life. Little did I know that a copy of “Surviving earthquakes for dummies” should have been part of this inventory as well. I was only six years old when this personal and natural disaster happened. We lived in a small, mildly sturdy seven-story apartment made of bricks.
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.
The top single risk that is likely to adversely impact on the Hot Site organization is an earthquake, which will result from the movements of seismic waves below the region’s surface leading to surface faulting and tremors among other related cases of landslides. I selected the risk because the region, Sunnyvale, California, where Hot Site is located is prone to earthquake due to its subduction around the ocean, and having a complex belt that has stretched miles away to the American belt. Hot Site risks an earthquake, a phenomenon that may result from the regions slippage along the extensively stretching fault.
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 effects caused by earthquakes are devastating. They cause loss of human life and have effects on infrastructure and economy. Earthquakes can happen at any time anywhere. In January 12, 2010 an earthquake of a magnitude of 7.0 hit the nation of Haiti. An estimation of 316,000 people were killed, and more than 1.3 million Haitians were left homeless (Earthquake Information for 2010). Haiti was in a terrified chaos. After the earthquake, families were separated because many of the members were killed. Homes, schools, and hospitals were demolished. People lost their most valuable belongings. It will take time for the country to recover from this terrible disaster. The long damages are economic issues, health-state, and environmental issues that effect in the beautiful island of Haiti.
Every geohazard is different based on lots of factors, such as the geological composition of the land in terms of rock types or tectonic activity, and the socioeconomic impact a hazard would have. For example, a large earthquake in the middle of barren land is likely to be less of a problem than a smaller-scale earthquake in a city. Some geohazards can have unexpected consequences from relatively far flung locations, for instance a wide-reaching pyroclastic flow from a volcano can cause damage far more widespread than many people would expect, especially depending on factors such as wind strength and direction and the volume of pyroclastic material.
To begin, the chapter talks about the occurrence of “unnatural hazards” within geographic locations who are most susceptible to natural disasters. Slum housing almost two thirds of the urban population are built on unstable hillsides and on deep gorges surrounding the seismically active Caracas (Davis, 2006). I think it is important to analyze the effects of weaker geographical locations because it does have great bearing on urban planning in developing countries. When countries lack the proper infustructure needed to prevent or deal with natural disasters, it creates a ripple effect of issue that disturbs the ecological system.
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).