Introduction to Earth Science - Research Paper Example

Earthquakes Earthquakes are said to occur as a result of the elastic strain of the part of Earth which is suddenly released by slip on a fault (Brown et al., 1992; Grotzinger et al., 2006). And the termed used to describe the series of events that eventually led to an occurrence of an earthquake is seismic cycle. Seismic cycle is a sequence of activities that consists of building up of elastic strain, releasing it in an earthquake and building the strain up again (Brown et al., 1992). It is helpful to use marker or markers to know the movement across the faults during seismic cycle. Figure 1 below shows some markers like inter-seismic, co-seismic and post-seismic stages in the Earth that often lead to the happening of an earthquake. 2 The best approach for measuring the size of an earthquake is by determining the orientation of the fault, the direction of the slip, and the area of the fault that was affected during the earthquake (Brown et al., 1992). Through this process, it will be possible to estimate the amplitude of the waves generated by the earthquake by considering the area of the fault that broke and the magnitude of the slip caused by the vibration. In other words, earthquake sizes are currently estimated based on the amplitude of their seismic waves (Brown et al., 1992; Grotzinger et al., 2006). Earthquake magnitudes are measured on the Richter Scales. The figure 2 below show the relationship among the magnitude of an earthquake, the area of a fault that broke in the earthquake, the amount of slip in an earthquake, and the amount of strain energy released in the earthquake (Brown et al., 1992) Magnitude Fault Area (km2) Fault Length (km) Slim (m) Energy (joule) Number/year 3 0.15 0.4 0.008 2x109 100,000 4 1.5 1.2 0.025 6x1010 15000 5 15 4 0.08 2x1012 3000 6 150 12 0.25 6x1013 100 7 1500 40 0.8 2x1015 20 8 1.5x104 120 2.5 6x1016 2 9 1.5x105 400 8 2x1018 Figure 2: Courtesy of Brown et al., 1992. 3 Because of the ways they affect human activities, earthquakes have been subjected to series of studies. One important aspect of the studies is to identify the causes of an earthquake, its size and its overall implications in the areas where it has struck. The old technique of analyzing these issues concentrate on the first seismic waves that emanate from an earthquake occurrence. These first seismic waves are referred to as first motions (Brown et al., 1992; Grotzinger et al., 2006). The first motions are then observed from a distant and analyzed to determine the focal mechanism of the earthquake. However, modern method of studying of earthquakes utilizes sophisticated analysis that may be difficult to explain because of its technical requirements. Lately, scientists are studying the impacts of earthquakes on the environments. Some of the questions experts are asking include but are not restricted the following: (i) Do earthquake cause social hygienic problems whenever it occur? (ii) How do earthquake affect the economy of a particular place where it has occurred. Some answers have been offered to explain the implications of earthquakes in our world; but some experts are still digging for more facts to identify the actual economic cost of an earthquake, and how such a catastrophe can be mitigated in the future (Brown et al., 1992). The most important thing about earthquake is finding the most efficient way to ignite alarm system to the people immediately it strikes. This would be able to minimize both human and economic losses the situation would have caused. In the developed 4 countries, policy makers are spending a lot of money to find out the most applicable earthquake signals that would encourage people to follow evacuation procedures as soon as the earthquakes occurred (Grotzinger et al., 2006). Countries like Indonesia and Japan where the occurrence of earthquakes seem to be once in every other week are constantly seeking the final solutions to the earthquake signal system so as to improve both the pre- and post-occurrence incidents, and subsequently save more lives and protect properties that would have been affected by the huge blast of the earthquakes. References Brown, G.C., Hawkesworth, C.J., and Wilson, R.C.L. (1992). Understanding the earth (2nd ed). Cambridge, UK: CUP Archive. Grotzinger, J.P., Jordan, T.H, Press, F., and Siever, R. (2006). Understanding the earth (5th ed). New York, NY: W.H. Freeman. 5 Volcanoes Volcanoes can be described as an opening in the earth’s surface which gives out red-hot melted rock, gases, ash, pyroclastic debris and chunk of rocks. It is generally believed that volcanic activity occurs when melted rock or magma forces its way up to the earth’s surface from a far distance below (Woods and Woods, 2006). Volcanoes have different physical appearances: some look like vents—holes or cracks in the ground, while others appear like domes, shields, or mountain-like structures with craters at the top (Woods and Woods, 2006; Grotzinger et al., 2006). Figure 1 below shows the main features of a volcano. Figure 1 6 It has been discovered that some of the most beautiful mountains in the world are volcanoes. For example, the Mount Fuji in Japan and Mount Saint Helen in the U.S. state of Washington. Actually, the word “volcano” is comes from the Roman god of fire named Vulcan. It was believed that Vulcan had a forge on the mountain Vulcano, which is a volcanic mountain on the Lipari Islands in Italy (Woods and Woods, 2006). The processes that lead to volcanic eruptions entails some series of underground activities, which include but are not restricted to the following processes: first of all, magma, which is also referred to as molten rock will be formed under the earth crust through some geological procedures. This molten rock would then find its way to the surface of the earth through some internal pressure within the earth crust. And the magma becomes lava when it reaches the surface of the earth. Hence, at the time of the eruptions, lots of lava will shoot out of the volcano and spread around the areas around the volcano. Sometimes, dangerous gases and debris also come out with the lava (Woods and Woods, 2006; Grotzinger et al., 2006). The lava could also be seen flowing around the ground. The speed of lava along the ground could be anywhere between 35 to 60 miles per hour. On most occasions, the lava carried debris along it and volcanic gas like sulphur could be seen emanating from the surface of the lava. Volcanic eruption is often a violent activity that causes severe damage to the environment and unleashes dangerous disasters whenever it occurs. Apart from the tremor and quakes that always follow the eruption, the lava flowing out of the crater could cause 7 environmental disasters. Arable farmland may be completely covered with poisonous debris and gases; roads, bridges and houses may be submerged under the heavy ashes; and people and animals may be killed in the course of the eruption. Averagely, ten volcanic eruptions occur in a year; and it estimated that over a quarter of a million people have been killed by volcanic activities in the last 300 years (Woods and Woods, 2006). This scale of destruction makes volcanoes of the dangerous enemies of human beings and the environment. As a result of this, scientists are constantly identifying the appropriate ways to mitigate the effects of volcanoes by creating a pre-eruption warning system, which would encourage people to evacuate before a volcano blasts off. It may take some years before a perfect warning procedure could be put in place to help prevent the catastrophe that often follow a volcanic activity. References Grotzinger, J.P., Jordan, T.H, Press, F., and Siever, R. (2006). Understanding the earth (5th ed). New York, NY: W.H. Freeman. Woods, M., and Woods, M. Volcanoes. Minneapolis, MN: Lerner Publications. 8 Global Climate Change The issue of global climate change has reached a serious level that it calls for more proactive approaches to stem the danger of the problem. Some of the proposed causes of the global climate change or global warming can be categorized into two broad classes: (i) Natural causes:- examples of the natural causative factors of the global warming include the changes in solar radiations, change in earth’s orbit and changes in ocean processes. In recent years, scientists have been able to prove that the solar output or radiation to the earth has become intense due to the depletion in the ozone layer that had previously protected the earth from such dangers. Similarly, the transition in the earth’s orbit has led to the changes in temperature at different locations on the earth, which invariably increased the temperatures of those places. The fluctuations recorded in the seas and other oceanic bodies have affected the natural land-and-sea breeze, which is a kind of energy transfer processes that helps to heat the land when the seas are at rest, and vice versa (Houghton, 2004). (ii) Artificial causes:- A number of artificial or man-made causes are responsible for the global climate change. Some of these man-made cause include but are not restricted to: (i) increased production of the greenhouse gases through the actions of men by deforestation or engaging in carbon dioxide-production activities like gas flaring and combustion of carbon-rich substances (Houghton, 2004). Human beings 9 are also responsible for the over-heating of the earth through the burning of fossil fuels and other unhygienic disposal of waste products. The global climate change has produced some physical manifestations that confirm that our earth is passing through some strategic changes. Nowadays, there are complaints of intense sunburns owing to the unprotected exposure to solar radiation. Previously, ozone layers have been helpful in preventing such scathing heat from reaching the earth. Likewise, oceans are drying up, and forests are being depleted (Karling, 2001). Therefore, the urgency of finding a lasting solution to the problem of global warming has created an opportunity for nationals to come together and forge a common solution to the problem. Although politics and commercial interests have always been a huge hindrance to the implementation of the solutions to global climate change in many countries; however, efforts have been made by the independent earth conservation organization and other concerned groups that earth must be seriously protected from the impending destruction. Recently, representatives of many governments met in Kyoto, Japan to deliberate on how to reduce the production of greenhouse gases. It is scientifically believed that greenhouse gases are mainly responsible for the variations in the earth’s temperature. The Kyoto Accord and other environmental meetings since then had concentrated on the way to reduce the emission of carbon dioxide in the world. A typical approach discussed but which many countries find economically 10 not feasible is to place a “carbon tax” on their citizens based on the amount of carbon dioxide they generated (Karling, 2001). Big corporations and multinationals have always been in the forefront of opposition to this carbon tax, and they make the little progress that had been made towards conserving our earth to be unsustainable. The sad news is that this trend of earth’s destruction would continue for many years to come until the governments, business organizations and individuals learn how to avoid carrying out actions or activities that could make our world unlivable! References Houghton, J.T. (2004). The global warming: the complete briefing. Cambridge, UK: Cambridge University Press. Karling, H.M. (2001). Global climate change. Hauppauge, NY: Nova Publishers. 11 Hurricanes Hurricanes are described as the huge storms that move with winds at a speed faster than 74 hours per mile. Hurricanes are characteristically accompanied by heavy rains and loud and deafening thunderclouds (Souza, 1996). Figure 1 below shows how hurricanes become quite powerful and surprisingly destructive. Figure 1: The winds are the primary drivers of hurricanes. The faster the winds, the more powerful the hurricanes would be. Figure 1 above reveals that hurricanes need air, winds and warm oceans water to move around. The required conditions are as simple as this: (i) warm ocean water gives energy to the hurricanes to become more destructive in nature; (ii) light winds outside the hurricanes direct their movements and help hurricanes to expand in sizes; (iii) 12 humid air produces the clouds of the storms. All these processes are constantly in motion as the hurricanes make landfall in one tropic place to another (Fitzpatrick, 2006). Hurricanes are also given different names in different parts of the world: In the pacific, they are known as typhoons; in the Caribbean, they are called cyclones. But in the United States, they are primarily called hurricanes. From observations, the hurricanes in America seem to be stronger than either cyclones or typhoons (Souza, 1996). Hurricanes can be categorized into some classes based on their average speed as calculated on the sustained movement of winds within 10 minutes. A mere depression occurs when the hurricanes move at 52km/h. It then becomes a cyclonic storm at about 87km/h; it reaches severe cyclonic storm at 117 km/h; and it finally becomes super-cyclonic storm at 220km/h. These designations reveal that the power of an hurricane is directly proportional to the speed of the wind carrying it in an estimated time period (Fitzpatrick, 2006). Several researches have been carried out about the possibility of mitigating the destructive effects of hurricanes. In the US alone, hurricanes cause untold level of destruction, both on human lives and the physical properties. It is estimated that hurricanes cause some states to lose billions of dollars a year (Souza, 1996). As a result of this, hurricanes become a threatening natural force that requires some strategic approaches to reduce the amount of destruction it causes yearly all over the world. 13 One of the prominent ways of controlling the impacts of hurricanes is to establish a pre-warming system that would alert people to take covers or evacuate to a safe haven before the hurricanes begin (Fitzpatrick, 2006). Warning system could be transmitted live on TVs, as it is done in the United States and through mobile networks like cell phones, PDAs and IPODs. Evacuation officers should be properly trained and made ready whenever the hurricanes want to make landfall at a particular place. However, hurricanes are still a serious issue in developing countries where there are always poor preparations to forewarn people about an impending hurricane or organize quick evacuation exercises in case the hurricane goes out of hand in destroying things. It will also be helpful if an independent organization like the U.N can establish a procedure where developed countries can share ideas with the developing ones about the latest technology or invention to announce a coming hurricane before it makes a dangerous landfall. In this way, more lives would be saved and many properties would be protected (Fitzpatrick, 2006). This suggestion is progressive and may eventually lead to a functional procedure for creating the appropriate awareness for the whole world concerning hurricanes. References Fitzpatrick, P.J. (2006). Hurricanes; a reference handbook. Santa Barbara, CA: ABC-CLIO. Souza, D.M. (1996). Hurricanes. Minneapolis, MN: First Avenue Editions. 14 Tectonic Plates In an attempt to explain the existence of many physical mysteries that have troubled everyone in this world, like how do mountains rise to their current heights or why do earthquakes or volcano cause tremor on the earth, geologists have tried to apply a scientific theory known as tectonics plate to describe how these physical structures came into being. The theory assumes that the Earth’s crust or lithosphere is segmented into huge blocks or plates, whose shape is comparable to that of soup bowls with an average thickness of 40miles. There are some six major plates and about a dozen minor ones which are believed to be in constant motion, gliding over a semi-molten layer under them. This continuous motion is believed to be responsible for the creation of geological features like Alps or the Himalayas as the continents are being carried along in the motion, colliding them against the Earth to form different physical shapes (Speicher, 1972). Some of the assumptions in tectonics plate theory are as follows: That all continents were once a single supercontinent that became broken into parts at the beginning of the age of dinosaurs, about 200 million years ago; and with this arrangement, United States appears to be getting closer to China than to Europe. All of the eastern United States was once parts of West Africa which collided with North America to form the Appalachians. 15 The sea floor is younger than the earth being 160-200 million years old, while the earth is estimated to be 4.5 billion years old. Figure 1 below reveal how physical structures or continents shift or drift to form new geological features. There is ocean to ocean convergence, whereby the oceanic plate and lithosphere are moved into a new structure due to the concept of oceanic drift. As shown in figure 1, it is also possible to ocean-continental convergence and continent-continent convergence. The essence of the convergence is to create a new geological feature that would take the place of the former physical structure. This theory could be used to explain why there are shells on the mountains instead of on the sea beds, where they are supposed to be, naturally (Condie and Pease, 2008). 16 The occurrence of earthquakes, hurricanes and other change in geological structures have, in part, supported the theory of tectonics plate. Continental drift over molten-like earth surface seems to have permitted the structural readjustments in oceans, continents and other geogolical structures (Speicher, 1972). However, the earth may benefit from this theory in the long run as some parts of the continents and oceans are moved over the lithtospheres to create features that could stand the current changes in tempratures. Incidentally, it may be possible to see a hot polar region, while the hottest Sahara desert becomes a cooler area. This would help transform the effects of the current global climate change (Speicher, 1972). The good news is that geologists are still researching how tectonics plate theory will positively transform the earth surface into structures or features that would become less problematic. At that time, there may be less occurrence of earthquakes, typhoons or hurricanes, and the sea beds would not be destroyed so that the marine life in them would continue to exist for both commercial and ecosystem purposes. References Condie, K.C., and Pease, V. (2008). When did plate tectonics begin on planet Earth? Boulder, CO: Geological Society of America. Speicher, J. (1972). Plate tectonics: a startling new view of our turbulent earth. Popular Science, 200 (6), 84-160. 17 Coastal Processes The coastal processes are regarded as a set of mechanisms that operate along the coastline, which causes various combinations of erosion and deposition (Shibayama, 2008). As a result of this, the land water always interfaces along the coastline in a dynamic nature that would foster equilibrium between them. This equilibrium helps to constantly prevent the overflowing of water (erosion) from destroying the coastline (Dean and Dalrymple, 2004). Interestingly, it is believed that the energy working in the coastal zone normally originates from tide, waves, wind and currents. Therefore, the release of this energy is often provided by the beaches, mudflats, marshes and mangroves (Shibayama, 2008; Dean and Dalrymple, 2004). Since the human use of the coasts require a definite amount of space, this has always caused some conflict leading to unstable coastal usage that mostly ends up in critical coastal erosion, sediment transport and accretion (Shibayama, 2008). Figure 1 below reveals how the coastal processes work. 18 From figure 1, it is possible to identify some forces that play significant parts in the coastal processes. They include but are not limited to: (i) environmental forcing; (ii) marine sediments; (iii) sea topography; (iv) erosion/sedimentation/accretion. The coastal processes are interesting but quite unpredictable (Dean and Dalrymple, 2004). This is why the entire processes are challenging to the coastal scientists who work hard to find out more about sediment transport, currents, denudation, deposition, erosion, flooding, diffraction, refraction and all other factors that play prominent parts in the coastal processes. It is an undeniable fact that sediment transport is the major coastal process. This is why coastal scientists are concentrating on this area of study. Findings have shown that great analysis and prediction of sediment transport have aesthetic, commerrcial, social, and scientific usefulness (Shibayama, 2008). The social usefulness of sediment transport is that if the coastal managers could apply any system that would reduce the pollution of the coastline through sedimentation, the beaches would be clean enough to attract many people going to the sea for relaxation. Invariably, the operators of seaside businesses would be able to benefit immensely from this circumstance, as many beach-combers would flock to the clean beaches. Hence, the scientific implication of this is that clean coastline would be good for the marine life under the sea, and scientists can now concentrate on other factors that may be affecting coastal processes. 19 The most interesting aspect of this observation is that every coastal process is dependent on the other; as a result of this, if the problem of sedimentation is completely managed, the other factors would be put under control (Dean and Dalrymple, 2004). Some main terms to describe the coastal processes are defined below: Erosion—the removal of sediment from a particular location by the action of wind or water Accretion—natural or artificial deposition of sediment in a particular location. Beach nourishment—the restoration of a beach by the mechanical placement of sand on the beach for recreational and/or shore protection purpose. Core shore transport—the displacement of sediment perpendicular to the shore. References Dean, R.G., and Dalrymple, R.A. (2004). Coastal processes with engineering applications. Cambridge: Cambridge University Press. Shibayama, T. (2008). Concept processes: concepts in coastal engineering and their applications to multifarious environments. Hackensack, NJ: World Scientific. 20 Hydrological Cycles The hydrologic cycle can be defined as the process strengthened by the sun's energy, which dramatically moves water between the oceans, the sky, and the land (Balek, 1983; Beniston, 2002). It is possible to consider the hydrologic cycle with concentration on the oceans, which controls over 97% of the planet's water. The sun leads to the evaporation of water on the surface of the ocean. The water vapor rises and condenses into little droplets which cling to dust particles. These droplets bring about the clouds. Water vapor usually remains in the atmosphere for a little time, from a few hours to a few days until it becomes precipitation and comes to the earth as rain, snow, sleet, or hail. This precipitation is absorbed (infiltration) or becomes surface running water which gradually flows into gullies, streams, lakes, or rivers. Water in streams and rivers flows to the ocean, seeps into the ground, or evaporates back into the atmosphere. Water in the soil can be absorbed by plants and is then transferred to the atmosphere by a process known as transpiration. Water from the soil is evaporated into the atmosphere. These processes are generally called as evapotranspiration. Some water in the soil flows downward into an area of porous rock which contains groundwater. A permeable underground rock layer which is capable of storing, transmitting, and supplying huge quantities of water is known as an aquifer. 21 Researchers have shown that there is more precipitation than evaporation or evapotranspiration occurs over the land but accounts for a larger portion of the earth's evaporation (86%) and precipitation (78%). The quantity of precipitation and evaporation is made equal all over the world. While certain regions of the earth have more precipitation and less evaporation than others, and the reverse is like possible, on a global scale over a few periods of time, but they will eventually become equal. Water can be found everywhere in the world. The figure 1 below demonstrates the complete hydrological cycles, and shows the relations between water and other substances in the universe. Hydrological cycles is composed of five main processes: (i) condensation; (ii) precipitation; (iii) infiltration; (iv) runoff, and (v) evapotranspiration. The continuous 22 circulation of water in the ocean, in the atmosphere, and on the land is fundamental to the availability of water on the planet. Only during the ice ages are there noticeable differences in the location of water storage on the earth. During these cold cycles, there is less water stored in the oceans and more in ice sheets and glaciers. Understanding the hydrological cycles in our world helps us to play our parts in conserving the environment and support the dynamic ecosystem. We should engage in practices that would not dry up our water faster than expected. We should use water carefully. References Balek, J. (1983). Hydrology and water resources in tropical regions. New York, NY: Elsevier. Beniston, M. (2002). Climatic change: implications for the hydrological cycle and for water management. New York, NY: Springer. 23 Self Assessment I learnt a lot of things in the course of researching about earthquakes, volcanoes, hurricanes, tectonic plates, coastal processes, hydrological cycles and global climate change. Some of the processes I undertook in this writing assignment include but are not limited to: Carrying out in-depth research about the topics and presenting only the cogent facts about them. Making sure that the statistics and other mathematical representations that are related to the topics are verified before using them. Verification of the facts through the use of peer-reviewed publications that have more originality and genuine ideas. Identifying the areas where the issues discussed in the topics affect the earth, environment and world economies. It is important to state that collecting the appropriate facts, concepts, statistics and records about the topics was not all that easy. I have visited the library several times to research the appropriate information I think would be valuable to this assignment. Selecting the right materials to be presented in the assignment called for pragmatic behavior, and the willingness to test all data to determine their usefulness in the final writing. Other challenges I had faced in the course of doing this assignment include questioning my choice of words. All the topics in this assignment have technical 24 expressions that are normally used in describing them. To fully understand these technical jargons, I have spent some time to understand their meanings. This had helped me discover which technical expressions to use at a particular point in time. I also spent time to familiarize myself with the writing procedure so that each important aspect of the topics is cleanly presented in paragraphs that would make reading them easy. I likewise avoided using difficult or incomplete expressions that could confuse readers. I found out that natural disasters are caused by some of the activities discussed in the topics. And that most of the problems we face in our environment today are about 40% man-made and 60% natural causes. Since it is impossible for us—human beings—to control the nature, I think we can do little to control our fate as far as these natural disasters are concerned. Human knowledge could be applied in inventing the best and accurate warning system that would give people the necessary warning before a volcano or earthquake occurs. As a result of this, we can be able to control the effects of these natural disasters on our environments, human lives and properties. This kind of research and writing assignment is so important in training my mind to identify the main issues bothering every person on this planet. It also broadens my knowledge of how to find solutions to any prevailing problem through the process of collecting vital information or data that could be processed in establishing a final solution to the problem. I think this kind of assignment will 25 likewise help students to develop their data-gathering ability and research presentation. Read More