...“Volcanic and seismic events are major pieces of evidence towards proving the plate tectonics theory is valid” Discuss the extent you agree with this statement. Plate tectonics is the theory used to explain the structures of the earth’s crust. Direct and indirect evidence can show us what is beneath our feet, or the composition of the crust. Volcanoes and earthquakes are both natural hazards, however are two of the most precise pieces of evidence to explain what is really happening up to 6371 kilometres away. In 1915, Alfred Wegener set out evidence for Continental drift using studies of continents fitting and glacial deposits samples. He discovered a large scale horizontal movement of continents in geological time. Rock types was one piece of evidence when discovering continental drift. The age, discovered by radiometric dating of rocks and distinct characters were both seen on two separate pieces of land. Other evidence such as Fossils from a fresh water Dinosaur, known as the Mesosauraus, is found on South America and Africa, there is no way this dinosaur could have swam across the Atlantic to populate on both lands. Although there was plenty of evidence for Continental drift, there was no reason of why the continents would be driven apart and together. This was until 50 years later, when geologist Harry Hess proposed his hypothesis on Seafloor spreading. He predicted that basaltic magma from the mantle rises to create new ocean floor at the Mid-Ocean Ridges. Seafloor...
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...Evaluate how plate tectonic theory helps our understanding of the distribution of seismic and volcanic events (40 marks) Outline the theories Supporting evidence Notes: * Alfred Wegner – suggested that continents were once all joined together in an ancient super continent called Pangaea. Land masses had drifted apart until they got to a certain position. Used 4 different pieces of evidence to help support his theory: 1. Continental Fit – If you placed certain continents together they look like they should/could have been joined together at some point. For example western seaboard of Africa and Eastern sea board of South America. 2. Geological Evidence – Rocks of similar type and age sharing the same formation can be found in South East Brazil and South Africa, which were believed to be joined. Also similar glacial deposits found in the Antarctica, South America and India. 3. Climatological Evidence – Similar coal deposits have been found in places such as Antarctica, North America and UK, all of similar age and all formed in tropical conditions. Neither of these places is still tropical therefore the coal must have drifted apart. 4. Biological Evidence – Fossil formations can be found on either side of the Atlantic. An example of this is the Mesosaurus, this reptile could not fly, however its fossils were found only in South America and South Africa. Therefore they must have been joined; otherwise the fossils would not be in the same place. * Paleomagnestism...
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...country, University of Utah researchers found. Share This: 125 "We detected seismic waves created by the oceans waves both hitting the East Coast and smashing into each other," with the most intense seismic activity recorded when Sandy turned toward Long Island, New York and New Jersey, says Keith Koper, director of the University of Utah Seismograph Stations. "We were able to track the hurricane by looking at the 'microseisms' [relatively small seismic waves] generated by Sandy," says Oner Sufri, a University of Utah geology and geophysics doctoral student and first author of the study with Koper. "As the storm turned west-northwest, the seismometers lit up." Sufri was scheduled to present the preliminary, unpublished findings in Salt Lake City Thursday, April 18 during the Seismological Society of America's annual meeting. There is no magnitude scale for the microseisms generated by Sandy, but Koper says they range from roughly 2 to 3 on a quake magnitude scale. The conversion is difficult because earthquakes pack a quick punch, while storms unleash their energy for many hours. The shaking was caused partly by waves hitting the East Coast, but much more by waves colliding with other waves in the ocean, setting up "standing waves" that reach the seafloor and transmit energy to it, Sufri and Koper say. While many people may not realize it, earthquakes are not the only events that generate seismic waves. So do mining and mine collapses; storm winds, waves and tornadoes; traffic...
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...A seismic tremor (otherwise called a shudder, tremor or quake) is the shaking of the surface of the Earth, coming about because of the sudden arrival of vitality in the Earth's lithosphere that makes seismic waves. Quakes can extend in size from those that are weak to the point that they can't be felt to those sufficiently vicious to hurl individuals around and decimate entire urban areas. The seismicity or seismic action of a territory alludes to the recurrence, sort and size of quakes experienced over a time frame, Quakes are measured utilizing estimations from seismometers. The minute size is the most well-known scale on which tremors bigger than roughly 5 are accounted for the whole globe. The more various quakes littler than greatness 5...
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...Discuss the view that the impact of earthquakes depends primarily on human factors: Earthquakes are caused by movement of tectonic plates that covering the earth’s surface. They occur at all plate boundaries; destructive, constructive and conservative, but the most intense tend to occur at subduction zones and conservative faults, such as the San Andres Fault in California. Every seismic event will be unique, and there are many factors influencing the extent to which it will have an impact on the environment and the populace. In many situations, both physical factors, related to the nature of the event and the topography of the area, and human factors, linked to demography and land use, have an influence on the effects of a hazard. When evaluating the impacts of an earthquake, the demography of an area will almost certainly have a large influence. Clearly, a very densely populated area will be more likely to have a higher death toll or a wider radius of influence than an event occurring in a more sparsely populated area, due to the simple fact that there are more people in the same amount of space to be affected. However it is not just this statistical fact that leads to a more people being affected. In many LEDC’s, the highest population density occurs in slum areas and shanty towns. The people living in these areas are ill equipped to cope with the effects of an earthquake due to a combination of factors, mostly centred around the conditions in which they live. The same is true...
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...Earthquakes and fault lines Scientists and geologists have a pretty good understanding of how the plates move and how this is related to earthquake activity. There are four different types of plate boundaries. First we have Divergent boundaries, where new crust is generated as the plates pull away from each other. Second we have Convergent boundaries and this is where the crust is destroyed as one plate is forced under another. Third we have the transform boundaries and this is where the crust is not created or destroyed as the plates slide horizontally past the other. Last we have Plate boundary zones where broad belts in which boundaries are not well defined and plate interactions are not clearly understood. The best known divergent boundaries is the mid-Atlantic Ridge, it is a submerged mountain range, which extends from the Arctic Ocean down South of Africa. This mountain range has been spreading apart for millions of years, which allows new magma to surface thus increasing the size of the mountains 2.5 centimeters each year. The two plates involved here are the American and the Eurasian plates and they are separating Iceland. The convergent boundaries are where the crust is being destroyed at about the same rate as it is being replaced in other areas of the world. These boundaries are long and deep trenches in the ocean and it are created by one plate being forced under another. These areas include the ring of fire which is a geographic region that has volcanoes that are...
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...E E 1.26 in 400/1.26=317.46km/inch E=35.5 N 119 W Determining the Epicenter Using 3 Seismographs Michelle Veitz This study determines the exact epicenter of a fictitious earthquake. Using 3 different seismograph reports from three locations (Albuquerque, Boise and Sacramento) and a map, we are able to pinpoint the exact epicenter. The epicenter was estimated to be 35.5 degrees North latitude and 119 degrees West longitude. Partial information was provided in a grid format regarding seismographic data of 3 locations. Using a seismograph report from location Albuquerque, Δt was determined. Using Vp and Vs provided, tp and distance to the epicenter was determined using formulas provided by the professor. After determining a scale for the map, the radial distance was determined by dividing the distance to the epicenter by the appropriate scale. Circles were placed around each location based off of those calculations. At the intersecting point of all three circles is the epicenter for this particular earthquake. These calculations are found in the grid below. Using a measurement of 24 seconds per tic mark on the seismograph, 96 seconds was used as the Δt for Albuquerque. Δt was given as 79.58 sec for Boise and 30.96 for Sacramento. Vp was given as 6.01 km/sec and Vs was given as 4.1 km/sec. Using the formula, tp = (Vs * ∆t) / (Vp – Vs), tp was determined for all 3 locations. Using formula Dist. = Vp km/sec * tp sec, the distances to the epicenter was calculated...
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...Tectonic Hazards: Earthquakes Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves that make the ground shake. When two blocks of rock or two plates are rubbing against each other, they stick a little. They don't just slide smoothly; the rocks catch on each other. The rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up. When the rocks break, the earthquake occurs. During the earthquake and afterward, the plates or blocks of rock start moving, and they continue to move until they get stuck again. The spot underground where the rock breaks is called the focus of the earthquake. The place right above the focus (on top of the ground) is called the epicentre of the earthquake.  Haiti Earthquake: What? A 7.0 magnitude earthquake When?12th January 2010 at 16.53 local time (21.53 GMT). Where?The earthquake occurred 18.457°N, 72.533°W. The focus of the earthquake was 13km (8.1 miles) below the surface of the earth. The short term effects of the Haiti earthquake are· Buildings being destroyed, roads and docks. Making it difficult to get aid to the people who need it. Example food, clean drinking water, clothes, cooking utensils, temporally shelters and most importantly drugs and medicines. · Without clean drinking water and dead bodies rotting in the hot sun the risk of life threatening diseases...
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...Unit 2 DB Subjective Probability “ A probability derived from an individual's personal judgment about whether a specific outcome is likely to occur. Subjective probabilities contain no formal calculations and only reflect the subject's opinions and past experience.” (investopedia.com, 2013) There are three elements of a probability which combine to equal a result. There is the experiment ,the sample space and the event (Editorial board, 2012). In this case the class is the experiment because the process of attempting it will result in a grade which could vary from an A to F. The different grades that can be achieved in the class are the sample space. The event or outcome is the grade that will be received at the end of the experiment. I would like to achieve an “A” in this class but due to my lack of experience in statistical analysis, my hesitation towards advanced mathematics, and the length of time it takes for me to complete my course work a C in this class may be my best result. I have a 1/9 chance or probability to receive an “A” in the data range presented to me which is (A,A-,B,B-,C,C-,D,D- AND F). By the grades that have been posted I would say that the other students have a much better chance of receiving a better grade than mine. I have personally use subjective probability in my security guard business in bidding on contracts based on the clients involved , the rates that I charge versus the rates other companies charge and the amount of work involved...
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... Probability – the chance that an uncertain event will occur (always between 0 and 1) Impossible Event – an event that has no chance of occurring (probability = 0) Certain Event – an event that is sure to occur (probability = 1) Assessing Probability probability of occurrence= probability of occurrence based on a combination of an individual’s past experience, personal opinion, and analysis of a particular situation Events Simple event An event described by a single characteristic Joint event An event described by two or more characteristics Complement of an event A , All events that are not part of event A The Sample Space is the collection of all possible events Simple Probability refers to the probability of a simple event. Joint Probability refers to the probability of an occurrence of two or more events. ex. P(Jan. and Wed.) Mutually exclusive events is the Events that cannot occur simultaneously Example: Randomly choosing a day from 2010 A = day in January; B = day in February Events A and B are mutually exclusive Collectively exhaustive events One of the events must occur the set of events covers the entire sample space Computing Joint and Marginal Probabilities The probability of a joint event, A and B: Computing a marginal (or simple) probability: Probability is the numerical measure of the likelihood that an event will occur The probability of any event must be between 0 and 1, inclusively The sum of the...
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...= {-20, -19, …, -1, 0, 1, …, 19, 20} Number of people arriving at a bank in a day: S = {0, 1, 2, …} Inspection of parts till one defective part is found: S = {d, gd, ggd, gggd, …} Temperature of a place with a knowledge that it ranges between 10 degrees and 50 degrees: S = {any value between 10 to 50} Speed of a train at a given time, with no other additional information: S = {any value between 0 to infinity} 4 Sample Space (cont…) Discrete sample space: One that contains either finite or countable infinite set of outcomes • Out of the previous examples, which ones are discrete sample spaces??? Continuous sample space: One that contains an interval of real numbers. The interval can be either finite or infinite 5 Events A collection of certain sample points A subset of the sample space Denoted by ‘E’ Examples: • Getting an odd number in dice throwing experiment S = {1, 2, 3, 4,...
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...the stage where one can begin to use probabilistic ideas in statistical inference and modelling, and the study of stochastic processes. Probability axioms. Conditional probability and independence. Discrete random variables and their distributions. Continuous distributions. Joint distributions. Independence. Expectations. Mean, variance, covariance, correlation. Limiting distributions. The syllabus is as follows: 1. Basic notions of probability. Sample spaces, events, relative frequency, probability axioms. 2. Finite sample spaces. Methods of enumeration. Combinatorial probability. 3. Conditional probability. Theorem of total probability. Bayes theorem. 4. Independence of two events. Mutual independence of n events. Sampling with and without replacement. 5. Random variables. Univariate distributions - discrete, continuous, mixed. Standard distributions - hypergeometric, binomial, geometric, Poisson, uniform, normal, exponential. Probability mass function, density function, distribution function. Probabilities of events in terms of random variables. 6. Transformations of a single random variable. Mean, variance, median, quantiles. 7. Joint distribution of two random variables. Marginal and conditional distributions. Independence. iii iv 8. Covariance, correlation. Means and variances of linear functions of random variables. 9. Limiting distributions in the Binomial case. These course notes explain the naterial in the syllabus. They have been “fieldtested” on the class of 2000...
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...[pic] [pic] Markov Chain [pic] Bonus Malus Model [pic] [pic] This table justifies the matrix above: | | | |Next state | | | |State |Premium |0 Claims |1 Claim |2 Claims |[pic]Claims | |1 | |1 |2 |3 |4 | |2 | |1 |3 |4 |4 | |3 | |2 |4 |4 |4 | |4 | |3 |4 |4 |4 | | | | | | | | |P11 |P12 |P13 |P14 | | | |P21 |P22 |P23 |P24 | | | |P31 |P32 |P33 |P34 | | | |P41 |P42 |P43 |P44 | | | | ...
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...Permutations The word ‘coincidence’ is defined as an event that might have been arranged though it was accidental in actuality. Most of us perceive life as a set of coincidences that lead us to pre-destined conclusions despite believing in a being who is free from the shackles of time and space. The question is that a being, for whom time and space would be nothing more than two more dimensions, wouldn’t it be rather disparaging to throw events out randomly and witness how the history unfolds (as a mere spectator)? Did He really arrange the events such that there is nothing accidental about their occurrence? Or are all the lives of all the living beings merely a result of a set of events that unfolded one after another without there being a chronological order? To arrive at satisfactory answers to above questions we must steer this discourse towards the concept of conditional probability. That is the chance of something to happen given that an event has already happened. Though, the prior event need not to be related to the succeeding one but must be essential for it occurrence. Our minds as I believe are evolved enough to analyze a story and identify the point in time where the story has originated or the set of events that must have happened to ensure the specific conclusion of the story. To simplify the conundrum let us assume a hypothetical scenario where a man just became a pioneer in the field of actuarial science. Imagine him telling us his story in reverse. “I became...
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...presence with probability 0.99. If it is not present, the radar falsely registers an aircraft presence with probability 0.10. We assume that an aircraft is present with probability 0.05. What is the probability of false alarm (a false indication of aircraft presence), and the probability of missed detection (nothing registers, even though an aircraft is present)? A sequential representation of the sample space is appropriate here, as shown in Fig. 1. Figure 1: Sequential description of the sample space for the radar detection problem Solution: Let A and B be the events A={an aircraft is present}, B={the radar registers an aircraft presence}, and consider also their complements Ac={an aircraft is not present}, Bc={the radar does not register an aircraft presence}. The given probabilities are recorded along the corresponding branches of the tree describing the sample space, as shown in Fig. 1. Each event of interest corresponds to a leaf of the tree and its probability is equal to the product of the probabilities associated with the branches in a path from the root to the corresponding leaf. The desired probabilities of false alarm and missed detection are P(false alarm)=P(Ac∩B)=P(Ac)P(B|Ac)=0.95∙0.10=0.095, P(missed detection)=P(A∩Bc)=P(A)P(Bc|A)=0.05∙0.01=0.0005. Application of Bayes` rule in this problem. We are given that P(A)=0.05, P(B|A)=0.99, P(B|Ac)=0.1. Applying Bayes’ rule, with A1=A and A2=Ac, we obtain P(aircraft present | radar registers) =...
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