|Top of Form Earthquakes Practice Test Your score was 39%. You answered 7 correct and 11 incorrect. 1. What is the probability of earthquake occurrence based on? a. strain buildup only b. location of foci c. magnitude of P-waves [pic] d. reoccurrence rates of earthquakes in an area and the rate of strain buildup 2.
A hazard can be defined as natural phenomena that produce negative effects on life. According to Dr Martin Degg at the University of Chester, a natural hazard only becomes a disaster if it threatens humans. In Degg’s model, the hazard circle includes all the physical factors while the factors that make a population vulnerable are mostly human. In other words a hazard that produces a disaster in one population may have only a limited effect on another less vulnerable population. Take for example the two earthquakes that affected Northridge and Haiti.
Discuss the view that the impact of the earthquake hazards depends primarily on human factors? An earthquake, a sudden violent shaking of the ground can be caused by a number of things from seismic activity and resulting in varying impacts. The cause of an earthquake are a result of built up pressure under the earth’s crust, the pressure comes from the movement of the tectonic plates, they can occur on any plate boundaries. Although the majority of the earthquake hazards come from the physical factors, human factors can determine the severity of the event. The impacts created from an earthquake can come from the physical factors of the size, the location of the epicentre and the surrounding areas such as a ground type and the lithology of the rocks.
This tells us that it’s a powerful earthquake, reaching and being felt by farther away places. This earthquake makes itself more dangerous with little or no warning. Earthquakes are probably the most dangersome natural occurring disaster encountered. South Carolina is located within the interior of the North American plate, far from any plate boundary. An earthquake is what happens when two blocks of earth suddenly slip past one another.
It registered a 7.0 on the Richter scale. The earthquake’s epicenter was extremely shallow at only 8.1 miles below ground, which released the energy close to the surface and intensified the shaking. The increased level of destruction led to a high loss of life. The earthquake epicenter was only 15 miles from Port-au-Prince and was the strongest earthquake to hit the area since 1770. “The 7.0-magnitude earthquake would be a strong, potentially destructive earthquake anywhere, but it is an unusually strong event for Haiti, with even more potential destructive impact because of the weak infrastructure of the impoverished nation” (Thompson, 2010, p.1).
It was miles away from the capital called Port au Prince. The quake moved horizontally, the tectonics plates moved past one another, southwest of the capital which was densely populated. An associate coordinator, Michael Blanpied, of the Geological Survey’s Earthquake Hazards Program described the plates as grinding and crushing past one another. He also said the quake was a relatively shallow earthquake as it occurred 6 miles below the Earth’s surface and that this caused the populated areas to be shaken extremely strongly. Rene Preval, the president of Haiti, said to the Miami Herald that she would think that the death toll would be “unimaginable”.
Countries that are more developed are usually prepared for the earthquake to occur because warnings around the area go out to make sure everyone knows that an earthquake is going to occur. However countries that are not economically developed have more problems because they don’t know when an earthquake is about to occur and they don’t have emergency plan for their earthquakes. In the USA earthquakes happen often and are mange very well because the government prepares people for earthquake. As the USA develops more over the years, we can see that there have been improvements. In the year 1906, San Francisco, had a major earthquake causing 3,000 people to die.
Recently, it was found out that the earthquakes that happened in Youngstown, Ohio near the end of 2011, were related to hydraulic fracturing. A recent report by Secretary of Energy Advisory Board Shale Gas Production Subcommittee stated that hydraulic fracturing caused these earthquakes to be triggered because of the high-pressured water being injected into the ground (Fracking and Seismic Activity). Some people think that because the earthquakes in Ohio didn’t have a great magnitude, fracking wont harm anything in the future. However, there is a potential that these earthquakes could get bigger as fracking occures more and more. All in all, we are really putting the environment and our lives in danger by using fracking.
The great earthquake broke loose some 20 to 25 seconds later, with an epicenter near San Francisco. Violent shocks punctuated the strong shaking which lasted some 45 to 60 seconds. The earthquake was felt from southern Oregon to south of Los Angeles and inland as far as central Nevada. The earthquake changed California forever but now The California Geological Survey’s Strong Motion Instrumentation Program (SMIP), which studies the effect of earthquake shaking on structures and soil to help guide engineering practices and protect public safety, (CA.Gov) has been honored as one of the top seismic programs of the 20th century by the Applied Technology Council. This is what helps to protect all of our homes, businesses, and churches in the event of an earthquake.
The 2004 Indian Ocean earthquake and resulting tsunami (Boxing Day Tsunami) was an event that caused great loss, destruction and trauma. Within this essay, the nature of the natural hazard, the factors that contributed to this disaster, and the preparedness of the region to handle such an event will be discussed. Furthermore the extensive recovery process and lessons learnt from this disaster will also be looked at. Hazards are a “potential threat to humans and their welfare arising from a dangerous phenomenon… that may cause loss of life, injury, property damage and other community losses of damage.” (Smith 2006, p.11) In the case of the Boxing Day Tsunami, it was the resulting tsunami, not the earthquake, which caused the destruction and ‘displacement of around 1.8 million people.’ (Smith 2006) When the water first receded, many peopl, ‘rushed out onto the once-covered reefs to pick up the stranded fish.’ (McCall 2014) Subsequently when the water eventually returned in the form of a tsunami, the chance of survival for those on the reefs was almost non-existent. Both natural and human factors contributed to transforming the hazard into a disaster.