The Phenomenon of Earthquakes and the Main Components of Earthquakes - Research Paper Example

? Your Lecturer's An Analytical Study of the Earthquakes as a Natural Disaster: An Examination of the Earthquakes in Lisbon (1755), San Francisco (1906) and Alaska (1964) Date I Introduction This paper examines natural disasters on a global level. It focuses on the phenomenon of earthquakes and identifies the main components of earthquakes. In the past, earthquakes have caused severe and considerable damage to properties lives and communities around the globe. This paper therefore analyzes the scope and effects of these natural events and identifies the main elements of it. The paper uses a practical approach to examine earthquakes by evaluating five specific cases cases. These cases include major events in: 1. The 1755 Lisbon Earthquake 2. The 1906 San Francisco Earthquake 3. The 1964 Alaska Earthquake 4. The 1960 Chilean Earthquake and 5. The 2004 Sumatra Earthquake The paper renders a very extensive research into these earthquakes and the effects they had on the lives and properties of the societies at the given points they occurred. It examines the elements of physical geography in the areas and the exact impact of the quakes on these areas. In arriving at this end, the following objectives are met: 1. An examination of the social factors that existed in these three regions prior to the earthquakes 2. The geographical analysis of the components of the earthquakes. 3. An evaluation of the effects of the earthquakes on human lives and property. II Scientific Background of Earthquakes “An earthquake is a series of vibrations or seismic (shock) waves which originates from the focus – the point at which the plates release their tension or compression suddenly” (Nagle & Guiness 263). Earthquakes involve the phenomenon where the earth surface shakes at certain points in time. It involves some kind of vibration that is emitted from deep within the earth's crust. Earthquakes result from some shocks that are remitted from within the earth's surface which is felt on the land and in the sea. Earthquakes often cause the damage of building and destruction of properties. The epicenter of an earthquake is the part of the surface of the earth which is the focus of the earthquake. Usually, the epicenter is the point on the earth where the highest impact of the earthquake occurs. Aside the epicenter, the earthquake is felt in other lands around the epicenter. However, relative to the epicenter, the other areas affected by the earthquake is much lesser than that of the epicenter. Earthquakes are emitted by a series of shocks. There are some large shocks whilst there are other smaller shocks. These shocks shake the earth surface and are known as tremors. The tremors that occur before the earthquake are known as foreshocks whilst those that occur after the major earthquake are known as aftershocks (Nagle & Guiness 265). In terms of occurrence, there dynamics of earthquakes vary with the layer within which an earthquake emanates. Primary waves are body shocks in the earth's interior. The occur deep within the earth and close to the earth's core. Secondary shocks occur nearer to the surface of the earth. They are known as surface waves. Their impacts are quite less than primary waves. The primary waves affect a wider surface area and have a higher intensity on the epicenter. Earthquakes are measured by two popular methods (Nagle & Guiness 266). One of them is the Richter Scale whilst the other is the Mercalli Scale. The Richter scale records the magnitude of earthquakes on a scale of 1 to 10. The measurement is based on logarithms and it increases exponentially on the scale of tens. Thus an earthquake judged to be 7 on the scale is ten times more than one that is 6 on the scale. That same earthquake (7) will be judged to be hundred times more than another that is 5 on the scale and so on. The Mercalli Scale however measures the earthquake in terms of its impact on the society. It is a more practical approach to measure how the earthquake was felt by the community that was affected by it. The Mercalli Scale puts earthquakes on a continuum of 1 to 12. An earthquake that is rated to be 1 is rarely felt by anyone in the area it affects. An earthquake that is rated 4 is felt indoors. It shakes some items in rooms and people within rooms realize the impact of the tremors and shocks. An earthquake rated 8 causes considerable damage to buildings. It destroys weaker buildings and shakes stronger one significantly. On the extreme end of the scale, an earthquake of 12 causes total damage to the place it affects. It is felt by everyone and there is serious implications for the entire society. An earthquake that measures 12 on the Mercalli Scale throws things into the air and it destroys all buildings and damages things conspicuously. Nagle & Guiness (266) identify eight main factors that influence the impact of an earthquake on a given society. These are the major things that determines the extent to which earthquake would cause damage to lives and properties in the earthquake zone. 1. The Strength of the Earthquake: How strong an earthquake is determines the extent to which it would damage things in the community. 2. The Population Density: This refers to the number of people living in a given geographical area. An area with a lot of people populated is likely to be affected more by a given earthquake than one with a limited number of people. 3. The Types of Building: The kind of buildings in a given geographical area determines the impact of the earthquake on that society. 4. The Time of the Day: The time of the day that an earthquake occurs is very important. It determines the concentration of people at various points in the society and affects the death toll. 5. Distance from the Epicenter: The distance of a given settlement from the epicenter of the earthquake is an important factor that determines the impact of an earthquake. 6. Types of Rocks & Sediments: The kinds of rocks that exists in the area that the earthquake occurs is very crucial. If the rocks of the area are solid and compact, they are likely to withstand the effects of secondary shocks, this is because they will just shake and there is a better chance that these settlements will not really feel the impacts. 7. Secondary Hazards: The presence of secondary situations that can add up to the damage determines the impact of an earthquake. In some cases, there are some natural possibilities like tsunamis that can lead to the destruction of massive properties and lives. 8. The Economic Development and Preparedness of the Society Affected: This is a very strong indicator of the effects of an earthquake on a given country. How prepared a country or community is for an earthquake is very crucial in determining the scope of the effects of an earthquake on a given country. In a situation where a country has advanced earthquake warning systems and rescue methods, the effects of earthquakes are considerably cut down. III Examples of Earthquakes All the three primary communities studied in this research are places that were at significant points in their development. There were various forms of social structures like population growth and migration that marked the high points of the development of these communities. Additionally, there were other factors that were inherent in these parts of the world when the earthquakes struck. This paper attempts to analyze and identify these major events and situations as they were, prior to the earthquakes. Lisbon in 1755 Lisbon was emerging as one of the most advanced countries of the world at that time. Lisbon was a part of the advanced Catholic State of the Iberian Peninsular which was once part of the Spanish Empire. A few centuries earlier, this part of the world was the most advanced and developed place of the world. By 1755, Lisbon's commercial strengths centered on its expansion into Brazil and the control of territories in that South America (Telles et al 25). The Portuguese were still amongst the most advanced nations on earth and the Catholic Church and its beliefs flourished in that part of the world (Telles et al 25). Portugal's buildings were made out of highly specialized architecture and this was marked by solid structures that were built to withstand thousands of years of wear and tear (Telles et al 25). This included baroque and other classical structures and buildings that made a very strong impression on the advanced nature of the nation. The architectural background of Portugal was further enhanced by the impact of planned urbanization (Laitenen & Cohen 12). There was an urban housing law that was operational since the time of King Manuel I [1495 – 1521] (Laitenen & Cohen 12). This law sought to standardize the design and urban regulation of cities in Portugal, including Lisbon. Lisbon port was also a major point for interaction with other lands in different parts of the world (Laitenen & Cohen 12). By the 1600s, about 100,000 inhabitants lived in the city of Lisbon (Laitenen & Cohen 13). About 20% of these inhabitants were slaves captured from Africa and brought into Portugal to work for their European masters (Laitenen & Cohen 14). The culture of Lisbon was also steeped solidly in Roman Catholicism and everything was attributed to some form of spiritual or supernatural causes (Mendes et al 147). This is strongly demonstrated in Voltaire's story Candide which is set around this time of the year and includes some components of the 1755 earthquake of Lisbon. San Francisco in 1906 San Francisco was building a strong entertainment industry at the turn of the 20th Century (Thomas 8). San Francisco's citizens had invested a lot of money and effort to build centers of entertainment and other commercial units (Thomas 8). This included theaters and a thriving commercial center that was built to provide world-class businesses with appropriate housing and premises from which they could interact with other global centers. One of the main components of the local population was the migrants who had moved into that part of America (Thomas 8). The main push for migration into San Francisco and different parts of California was the gold rush of the late 1800s (Fradkin 193). This gold rush led to serious wars with the Native Indians who lived in that part of the world. These Indians were killed in large numbers and by 1900, San Francisco was almost extinct and free of American Indians (Fradkin 193). San Francisco seemed to have been developing to become the capital of California and maintained strong trading links with different parts of the world (Hough 71). It gradually gained the reputation of being the main center for trade and commerce in the West coastline of the United States. Alaska by 1964 Alaska had been a piece of land in the extreme north of the American continent which had been controlled in various forms by America. Alaska was ceded to the Americans rather than the Canadians who controlled most of the adjoining lands. The US government controlled the lands in Alaska throughout the 1900s. Although the population density of Alaska was extremely small, it contained numerous natural resources that gave hope for economic exploration. Alaska became a state in 1958 after the Alaska Statehood Act of 1958 was enacted (Hill and Yeager 81). The US government developed some property in Alaska with the hope of tapping into its vast natural resources and economic wealth. As a state of the United States of America, Alaska gained several preferences in its development (Naske 91). In 1950, the capital of Alaska, Anchorage adopted a Uniform Building Code (National Research Council 247). Under this code, the buildings of Alaska were to be earthquake resistant. The country was to ensure that the standards remained high and little negativity could occur when an earthquake or tremor occurred. Alaska experienced fast development and growth in the late 1950s and early 1960s because of its admission to the Union (Mason et al 2). The company built downtown buildings and extended blocks and schools to encourage migration from mainland America (Mason et al 2). This vision was meant to enhance the community and increase the number of people to build a thriving state community. Scientific Impacts of the Earthquake Lisbon Earthquake of 1755 The Lisbon earthquake occurred at 9.40 on Sunday November 1, 1755 (Kozak & Cermak 131). The earthquake is seen as one of the most severe to hit Europe. The earthquake lasted for a period of about 3 to 6 minutes (Kozak & Cermak 131). The epicenter of the Lisbon earthquake believed to be somewhere in the Atlantic ocean, 200 kms away from Portugal (Kozak & Cermak 131). The epicenter stood in the the point that linked the Iberian Peninsular with Africa and is believed to be a point where the plate tectonics occurred in the separation of the major continents of the world. The earthquake is believed to be as high as 9 on the Richter Scale (Kozak & Cermak 131). This means that it was amongst the highest earthquakes ever to occur in Europe. The quake was felt as far as in the Scandinavia and parts of Africa. Within the under six minutes that the earthquake occurred, it caused a major shaking and destruction of two-thirds of Lisbon's houses (McCormmach 79). This led to the destruction of most houses including the King's palace. Since the epicenter of the earthquake lay in the Atlantic ocean, there was a major Tsunami that was triggered by the earthquake (McCormmach & Jungnickel 139). The Tsunami caused the water level of the sea to shrink considerably. Many eye witness accounts indicate that the Tsunami led the coastline of Portugal to recede for several meters. This can be attributed to the shaking of the earth's surface by the impact of the quake. This caused the water levels in certain parts of the Atlantic to rise to extremely high levels. This caused all the waves of the sea on the Portuguese coastline to go back. Within minutes after the coastline receded, a giant wave of about 40 feet started approaching the Portuguese coastline (McCormmach 79). The wave became another secondary factor that added up to the impact of the disaster of the earthquake. It hit the Portugues coastline and destroyed more lives and properties. San Francisco Eartquake of 1906 The San Francisco earthquake occurred at 5.12 am on 18th April 1906 (Kozak & Cemark 179). The quake was powerful and it hit San Francisco and the northern coast of California. The San Francisco Earthquake is documented to be the strongest in America's history (Kozak & Cemark 179). The San Francisco earthquake originated from the San Andreas Fault and can be traced to an area two kilometers in the coast off San Francisco (Kozak & Cemark 179). The earthquake can be seen to be a secondary wave because it occurred just 20 km close to the surface of the earth's crust (Kozak & Cemark 179). Normally, such quakes that occur close to the surface of the earth do not cause much damage. However, the proximity of the San Andreas Fault's epicenter to the city of San Francisco made the quake a very serious event. A mere 2 kilometers from the epicenter ensured that the event became a major incident that caused a lot of damage to lives and properties. The impact of the quake is said to be around 7.7 on the Richter Scale (Kozak & Cemark 179). This shows that it was a serious event and many things on the surface of the earth were shaken by the event. The quake lasted for about forty seconds. However an aftershock of the earthquake also lasted for another 25 seconds which was less intense than the original one. The San Francisco earthquake caused tremors in Los Angeles and other parts of the United States. However, the effects and aftermaths were felt vertically and horizontally across America at various degrees throughout the country. The Anchorage Earthquake of 1964 The Alaskan earthquake of 1964 occurred on March 27 (Vanasse 81). It is ranked to be the second most intense earthquake ever to be recorded (Vanasse 81). It measured 9.2 on the Richter Scale and was only second to the Chilean Earthquake of 1960 (Vanasse 81). The Alaskan earthquake's epicenter was located about 75 kilometers from Anchorage the capital. It lasted for four to seven minutes and this led to the shaking of buildings and slopes throughout Alaska (Vanasse 81). The earthquake triggered a Tsunami that occurred intermittently after the shaking of buildings and slopes ended. Chilean Earthquake of 1960 Veblen et al (507) reports that The Great Chilean Earthquake of 1960 occurred on 22nd May, 1960 and is the most powerful earthquake to be documented in history. The earthquake was rated at 9.5 on the Richter Scale. The epicenter of the Chilean Earthquake was about 570 kilometers from the capital, Santiago. The earthquake caused the loss of between 2,000 and 5,000 lives (Veblen 509). The figures are not certain because Chile was made up of a lot of indigenous people who were not immediately available to provide information about the disaster. The earthquake destroyed property worth about $550 million in 1960 and this include natural resources like the rich forests of South America. Sumatra Earthquake 2004 The Sumatra earthquake occurred on 26th December, 2004 (Kanamori 1927). Although it was quite lower than the Chilean and Alaskan Earthquakes, the Sumatra Earthquake was the most destructive in recorded in this century (Kanamori 1928). The Sumatra Earthquake hit Southern Asia and led to a major tsunami that led to the killing of about 300,000 people (Kanamori 1931). It hit Indonesia, Sri Lanka, India and Thailand. Impact of the Earthquakes on the Three Primary Areas Under Study Impacts of the Lisbon Earthquake The Lisbon Earthquake led to the death of between 40,00 and 100,000 Lisbon inhabitants (McCormmach 79). Lisbon was a city with about 270,000 inhabitants. This means that about a quarter of the nation's population was lost to the earthquake. At the time of the 1755 quake, the world was strongly stepped in the belief that everything was determined by God (McCormmach 79). Protugal, being a very religious nation and one of the most powerful nations in the world at that time had absolutely no plans to deal with earthquakes. The quake occurred on All Saints Day when most of the Catholics were at Church (Cormmach 79). Due to this, most people were out in large chapels and worship places and large numbers of people could be killed in buildings that were strongly hit by the quake. The capital city of Portugal was a well built and fortified city. They had the most advanced structures at that time since they were amongst the most advanced nations at that era. Due to this, a large proportion of the best and most durable buildings of the world were razed down by the quake. An estimated half of the city's buildings were destroyed (Kozack & Cemerk 131). Most of these buildings were destroyed by fire, which was started by the stoves of people's homes meant to cook the festive meals. The Tsunami also added up to the destruction. Many people in Lisbon ran to the coastline where there were no buildings. These people experienced the effects of the large wave that hit the quarters of Portugal close to the beach. Many of them died and valuable properties in that era were lost through the destruction. The Lisbon earthquake was one of the events that led to the development of science and reduced the reliance on optimism (Prothero 18). Religious beliefs were questioned strongly because the disaster occurred on a day where most of the Catholics of Portugal were busy praying. This led to skeptical analysis of natural events by scholars in Britain and other parts of Northern Europe (McCormmach 71). Impact of the San Francisco Earthquake An estimated casualty figure of 3000 was reported for the 1906 San Francisco earthquake. This is the highest natural disaster to ever hit the United States. It ranks on the same level as the Pearl Harbor disaster and the events of September 11th. The San Francisco earthquake is estimated to have caused economic losses as high as $524 million in 1906 price levels (Kozak & Cermak 179). This is a lot of money because at that time, the value of the US dollar was extremely high. There was a massive destruction of properties and the death of many people in San Francisco and adjoining communities. In 1906, San Francisco was amongst the most modern cities in the world. San Francisco had electricity and telephone connection. However, due to the fact that there were no precautions, the electricity triggered a lot of fires which destroyed more properties and lives than the shaking itself (Kozak & Cermak 179). Also, many of the buildings were still wooden structures so they caused the burnings and the fires to spread quite easily. The fire destroyed over 500 city blocks (Hansen & Emmet 91). This was an extensive damage which can be attributed to the secondary causes like electricity and the use of gas in a community that had little safety regulation in respect to earthquakes. The San Francisco earthquake laid the foundation for the development of Seismology which seeks to study earthquakes and prevent their effects on the society (Prothero 22). The Anchorage Earthquake Although Anchorage's earthquake is the second most serious recorded earthquake in history, its impact on human lives and properties was far less than many other earthquakes. This is because Anchorage was not a heavily populated place and there was limited investment in Alaska in 1964 when the earthquake occurred. A total of 15 people died due to the earthquake (Vanasse 81). About 30 city blocks of commercial and residential buildings were destroyed (Vanasse 81). The Tsunami of the Anchorage earthquake hit the west coast of the United States and Canada. Thirteen people died in California whilst another four died in Oregon from the Tsunami (Vanasse 81). Millions of properties in the West Coast were destroyed by the Tsunami of the earthquake. IV Risk Assessment Earthquakes can be monitored by an analysis of the faults underneath the earth's surface and examinations of satellite images (Wright 2893). In other words, if the arrangements of faults and the sub-structures of the earth are known, it can be easy to predict where the next earthquake may occur and when. “Satellites and ground based facilities may detect earthquake precursors in the ionosphere a few hours a day before the main shock” (Jason 169). The satellite systems have been set up in different parts of the world to create a warning and alert systems for nations and communities before they hit a given area. Other sound wave detector systems have been developed (Nagle & Guiness 267). They detect changes in waves in the earth and provoke warnings of earthquakes before they hit a given area. However, due to the fact that some of these detectors have inherent limitations, they do not serve their full purpose all the time. Thus, some communities have come to view earthquakes as natural evils that will occur from time to time (Nagle & Guiness 267). In the Houston/Galveston area, earthquakes can hit the community at any point in time. This is because these quakes are natural events that can be hardly controlled by any human beings. However, it does not seem to be very likely because the Houston/Galveston area does not really lie on a major faultline like Japan. The Geological Survey Department of the government has a lot of detectors that can identify risks and warn the communities within a short notice. Although there are little drills and education, the media could be used to prompt alerts and initiate some timely actions to reduce disasters. Conclusion Earthquakes are major natural disasters. It involves the shaking of the earth's surface for a given period of time. Earthquakes can be destructive to human lives and properties. The impacts of earthquakes can vary according to some important aspects of the society it affects. The major earthquakes had impacts on the societies and affected some crucial elements of the nations that they hit. Risk assessment systems for earthquake detection are still undergoing major changes. Sources Fradkin Philip. The Great Earthquake & Firestorms of 1906. University of California Press. 2005. Print. Hill, Barry & Yeager Jim. Alaska North Slope: Requirements for Restoring Land After Oil Production. DIANE Publishing. 2003. Print. Hough, Sugar Elizabeth. Finding Fault in California: An Earthquake Tourist's Guide. 2004. Print. Jason Susan, Pulinets Sergei, Curiel Alex Da Silva, Liddle Doug. “Earthquake Science Research With a Microsatellite”. The Royal Society. 361. Journal. 2002. Kanamori, Hiroo. “Lessons from the 2004 Sumatra-Andaman Earthquake” Philosophical Transactions of Royal Society. 364. 2006. Journal. Kozack Jan & Cermek Vladmir. The Illustrated History of Natural Disasters. London: Springer. 2010. Print. Laitenen Ritta & Cohen Thomas Vance. Cultural History of Early European Streets. BRILL Publications. 2009. Print. Mason Owen, Neal William & Pilkey Orrin. Living With The Coast of Alaska. Duke University Press. 1997. Print. McCormmach Russell. Weighing the World. London: Springer. 2011. Print. McCormmach Russell & Jungnickel Christa. Cavendish American Philisophical Society. Mendes-Victor Luiz, Oliveira Sousa Carlos & Azevedo Joao. The 1755 Lisbon Earthquake Revisited. London: Springer. 2008. Print. Nagle Garrett & Guiness Paul. Geography. London: Hodder Education. 2011. Print. Naske, Clause & Slotnick, Herman. Alaska: A History of the 49th State. University of Oklahoma Press. 1994. Print. National Research Council (USA). The Great Alaska Earthquake of 1964. Vol 1 National Academic Press. 1968. Journal. Prothero Donald. Catastrophes!: Earthquakes, Tsunamis, Tornadoes and other Earth Shattering Disasters Baltimore, Maryland: JHU Press. 2011. Print. Telles, Edward Eric. Race in Another America: The Significance of Skin Color in Brazil. Princeton University Press. 2004. Print. Thomas Gordon. The San Francisco Earthquake Drama. Digital Publishing. 1983. Print. Vanasse Deb. Insider's Guide to Anchorage & Southcentral Alaska Globe Pequot. 2009. Print. Veblen, Thomas, Kitzberger Thomas & Antonio Lara. “Disturbance & Forest Dynamics Along a Transect From Andean Rain Forest to Patagonian Shrubland” in Journal of Vegetation Science. 1992. Journal. Wright Tim. “Remote Monitoring of the Earthquake Cycle Using Satellite Radar Interferometry” The Royal Society. 360. 2002. Journal. Read More