...PLATE TECTONICS THEORY The theory of plate tectonics is widely accepted by scientists and it derived from the Continental Drift theory devised by Alfred Wegener. * In the 17th century is occurred to people that Africa and South America look as though they once fitted together. There were suggestions that the continents have moved apart. * In 1912, Alfred Wegener proposed the theory of continental drift. He suggested all continents were once joined as one supercontinent called ‘Pangaea’ which drifted apart. * He based the theory on geological evidence and fossils, but could not back it up with a mechanism explaining how the continents separated in the first place. * In the 1950’s palaeomagnetism provided evidence supporting continental drift. * In the 1960’s the process of seafloor spreading was discovered which provided a mechanism for continental drift. * The continental drift theory was further developed after these findings and became the foundations of plate tectonics theory. Evidence for the theory: Geology: - Areas of South America and Africa have rocks of the same age and composition. If you fit the continents together the distribution of the rocks match up. You can also match up the age, rock type and distribution of some mountain ranges. E.g. mountains in Scotland, Norway, Sweden and Finland are similar to those on the east coast of North America. These rocks and mountains must have formed under the same conditions and in the same...
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...Evolution and Theory of Plate Tectonics The most important and vital development of plate tectonic theory and evolution appeared to be among the most crucial scientific achievements in the 20th century. The theory concept offers a relevant structure towards the knowledge of all natural Earth attributes. It additionally provides one particular framework with regard to the knowledge of both planet's origin and outlook. Notably, the evolution of life on the planet remains significantly impacted by plate tectonic processes. This may involve the historic, societal, and cultural advancement of humanity. In other words, plate tectonic theory is an encompassing conjecture regarding different scientific theories that demonstrate the naturally occurring Earth characteristics have actually formed the historical past from the solid Earth, the oceans, the atmosphere, and all life organisms. Many scientific theories are so well established that no new evidence is likely to alter them substantially. For example, no new evidence will demonstrate that the Earth does not orbit around the sun (heliocentric theory), or that living things are not made of cells (cell theory), that matter is not composed of atoms, or that the surface of the Earth is not divided into solid plates that have moved over geological timescales (the theory of plate tectonics). Like these other foundational scientific theories, the theory of evolution is supported by so many observations and confirming experiments...
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...The Development Theory of Plate Tectonics * Introduction In this report I will be describing the theory of the Plate tectonics and showing its main points of development. There are matches between the shapes of South America and Africa. The two continents look like pieces of a jigsaw. Alfred Wegner thought that this meant that the continents where moving. They had once been joined together. He looked for evidence which was recorded in their rocks. In 1912 Wegner presented the idea of continental drift and his supporting evidence to a meeting of the Geological Society of Frankfurt. Geologists around the world read the English Translation of his book the Origin of Continents and Oceans which was published in 1922. He found interesting evidence from mountain chains, rocks and fossils on different continents. However most geologists reject such a grand and unlikely explanation of these explanations. Wegner Claimed: Fossil plants from both Africa and South America were identical. Reptile fossils matched too. People claimed he couldn’t just draw conclusions from a few fossils. They thought that there could once have been a land bridge joining Africa and South America. Wegner disagreed with the idea and asked for the evidence of there being a land bridge. The rock types on each continent fit like pictures on a jigsaw. The continents were once joined together. He claimed continents moved slowly. However one of the key principles of geology was to ‘use the present to interpret...
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...Developed in the 1950’s through to the 1970’s, plate tectonics is the scientific theory first proposed and elaborated by scientist, Alfred Wegener in 1912. The theory explains that the lithosphere is divided up into multiple plates that are moving constantly. (Cloos, 2018). This theory is regularly being adapted and developed as it has been through the past 400 years by several scientists. At first scientists, including Wegener only compiled a small amount of evidence supporting this theory. However, scientists have now composed a more accurate and reliable hypothesis about the movement of all contents as well as the forming of several of the Earth’s geographical features, such as earthquakes, volcanos, tsunamis and mountain ranges. The scientific...
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...The Development Theory of Plate Tectonics * Introduction In this report I will be describing the theory of the Plate tectonics and showing its main points of development. There are matches between the shapes of South America and Africa. The two continents look like pieces of a jigsaw. Alfred Wegner thought that this meant that the continents where moving. They had once been joined together. He looked for evidence which was recorded in their rocks. In 1912 Wegner presented the idea of continental drift and his supporting evidence to a meeting of the Geological Society of Frankfurt. Geologists around the world read the English Translation of his book the Origin of Continents and Oceans which was published in 1922. He found interesting evidence from mountain chains, rocks and fossils on different continents. However most geologists reject such a grand and unlikely explanation of these explanations. Wegner Claimed: Fossil plants from both Africa and South America were identical. Reptile fossils matched too. People claimed he couldn’t just draw conclusions from a few fossils. They thought that there could once have been a land bridge joining Africa and South America. Wegner disagreed with the idea and asked for the evidence of there being a land bridge. The rock types on each continent fit like pictures on a jigsaw. The continents were once joined together. He claimed continents moved slowly. However one of the key principles of geology was to ‘use the present to interpret...
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...Sea-floor spreading, the theory of plate tectonics, and continental drift, are three different theories stating three different things. These theories have many aspects that they share, while they also have their own unique aspects. The theory of sea-floor sreading says that molten material is shot up from the mantle through mid-ocean ridges and cools, forming magnetic strips across the ocean floor. Then, as the molten material cools it gets heavier and sinks into trenches to start this process all over. sea-floor spreading is a proven theory. The theory of plate tectonics says that the earth is divided into many equal plates that are constantly moving, due to convection currents. The continental drift is the theory that all of the continents...
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...Wegener's theory Continental drift-In 1915, the German geologist and meteorologist Alfred Wegener first proposed the theory of continental drift, which states that parts of the Earth's crust slowly drift atop a liquid core. The fossil record supports and gives credence to the theories of continental drift and plate tectonics. Pangea was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It formed approximately 300 million years ago and then began to break apart after about 100 million years. Unlike the present Earth, much of the land mass was in the Southern Hemisphere. Pangea was fully assembled by the Early Permian Period, some 270 million years ago. It began to break apart about 200 million years ago, during the Early Jurassic Period, eventually forming the modern continents and the Atlantic and Indian Oceans.The giant ocean that surrounded the continent is known as Panthalassa. The movement of Earth's tectonic plates formed Pangaea and ultimately broke it apart. Pangaea existed during the Permian and Triassic geological time periods, which were times of great change. This therefore shows that a certain extent of tectonic activity took place 200 million years ago to form our world that we know today. The idea of Pangea fitting together in a jigsaw fashion compared to how convection currents dictate the movement of the plate boundaries it can be seen as tangible that these pieces were to fit together very easily, however certain processes of...
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...Evaluate how plate tectonics theory helps our understanding of the distribution of seismic and volcanic events. Plate tectonics is a relatively new science. It’s partially explained in the sense that we still don’t know fully about how the plates came together, what they were before they were the seven continents we know today. We already know, or have a theory, about what our world was like a long time ago and so if we already know that the plates can pull and push against each other, then surely there must have been a different set up to the one we have now. There is a theory that we were once a supercontinent called Pangaea that began to break up around 200 million years ago. Using plate tectonics, we can explain, predict and see which type of seismic and volcanic events are related to plate tectonics, using more theories like Pangaea to explain them. Covering our earth’s surface there are seven major plates. These plates cover the inside structure of our earth, which consists of our inner core, our outer core, the mantle and then the crust which is what the plates are made out of. Plate tectonics is the theory of these plates moving along the earth’s lithosphere. The lithosphere is in the upper mantle and the lower crust and is responsible for continental drift. This is also because of the convection current running underneath and pulling and pushing the plates apart and together, causing them to converge and destruct. There are two types of plates, oceanic and continental...
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...and intruded during an eruption. The plate tectonic theory was developed by Alfred Wegener in 1912, however initially his theory of how the plates all ‘fit together’ was ignored as there was simply not enough evidence. After technology had significantly advanced later in the 20th Century, the theory was developed further by several scientists. This theory suggests that the crust is split into a number of plates, all of which float on molten mantle rock and are constantly moving on the Earth’s surface. We are also now aware that there are two types of plate, oceanic and continental and it is the movement of these two plates that can cause both volcanic and seismic events. However these events are not the only pieces of evidence that prove the plate tectonic theory is valid; there are many other factors which include sea-floor spreading and fossil distribution. Pyroclastic materials and molten magma escape the mantle and emerge above the Earth’s crust through volcanos. All of Earth’s active volcanos are distributed in clusters around the pacific ocean, southern Europe, the east coast of Africa and through the Atlantic Ocean. These specific locations are all as a result of the nearby constructive and destructive tectonic plate boundaries, this is known as ‘The Ring of Fire’. It is named so because of the large concentration of a large, ring like formation of volcanos around the Pacific Ocean, which provides strong evidence for the above theory and statement. The reason there is...
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...According to the plate tectonic theory, the earths crust is made up of 8 main plates, as well as a number of smaller ones. These plates float on top of the asthenosphere and move around quite regularly. This movement causes interaction between the plates which is thought to bring about seismic and volcanic events at its margins. Therefore the plate tectonics theory is a key concept in understanding the distribution of seismic and volcanic events. Plate tectonic theory was first suggested by Alfred Wegener in 1912. He believed that a single continent called Pangea existed around 300 million years ago before splitting it began to split because of continental drift, into two continents and continuing to split to form the continents we see today. His theory was supported by both geological and biological evidence, such as the bulge of South America seeming to fit into the indent of West Africa. He believed this suggested that they were once attached and had been separated through continental drift. Later evidence was also found as fossil remains of the reptile mesosaurus were found in both South America and Southern Africa. It is unlikely that the same reptile could have developed in both area or that it could have migrated across the Atlantic especially due to the fact that the reptile was believed to be a poor swimmer. This continental drift leads to seismic and volcanic events and is very important in understanding their distribution. Although Wegeners ideas seemed simple...
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...towards proving that plate tectonics theory is valid” Discuss the extent to which you agree with this statement. (40 Marks) The theory of plate tectonics is a relatively new idea – only conceived and developed within the last 100 years and is now generally accepted as the explanation for the causation of earthquakes and volcanoes and where they occur. It has now replaced the theory that tectonic events are caused by god in most western countries. The theory of plate tectonics was first developed by Alfred Wegener in 1912. He saw that the continents seem to have a jig-saw fit e.g. Africa and South America coastlines fitting together, suggesting that they were at one time joined together as part of a super continent called Gondwanaland and the other super continent Laurasia was in the north. Later evidence supported this – the fossilised remains of a dinosaur, the mosasaurs, was found on the coasts of Brazil and Gabon. There were also the same fossilised pollen species and rock sediments on these coastlines. Wegener’s ideas, though simple, were proved further right and built upon which further increased our understanding of tectonic events. Sea floor spreading was discovered showing that rock is being created and destroyed, leading us to believe in the existence of plates and plate boundaries. Sea floor spreading was shown in the Atlantic, where it is believed the Eurasian and North American plates are moving apart, at what is called a constructive plate boundary. Here magma...
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...“Volcanic and seismic events are major pieces of evidence towards proving that plate tectonics theory is valid”. Discuss the extent to which you agree with this statement. Plate tectonics is the theory that suggests that the Lithosphere is separated up into approximately twelve plates that can be moved around via convection currents, changing the land and sea formations across the globe. Since interest began during the early 20th century a variety of propositions have been put forward to suggest the existence of plate tectonics. The most prominent of these theories is the existence of seismic waves and volcanic activity, especially the location and distribution of these. Along with these theories is the discovery of fossils and their locations across the globe, as well as the shape of the existing continents and the “jigsaw” theory. During the 17th century Francis Bacon noted that the West coast of Africa and Europe coincidentally looked as though they would fit with the East coast of the Americas. However, Bacon had little evidence for this theory, meaning it was swiftly forgotten. During the 1920’s, Alfred Wegner, proposed that the formation of the continents today has occurred via continental drift. However, Wegner goes on to suggest that 300 million years ago there was a single landmass, commonly known as Pangaea, as shown in Figure 1.1. Pangaea was one supercontinent that existed during the late Palaeozoic and carrying on into the early Mesozoic eras. It consisted of...
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...that plate tectonic theory is valid. Discuss the extent to which you agree with this view. (40) Plate tectonics is the theory that explains the structure and motion of the Earth’s lithosphere. The theory states that the Earth’s crust is split into large sections called tectonic plates, and these move relative to one another creating boundaries at which plates converge, diverge and move past each other. Alfred Wegener pioneered the theory of continental drift in the early 1900s which he supported with multiple pieces of evidence. Perhaps the earliest indicator of the theory was the apparent fit of some of the Earth’s continents; analysis of these coastlines, notably the eastern edge of South America and the western edge of Africa, has shown that they are very similar geologically suggesting that at some point in the Earth’s history the landmasses were joined together. Another indicator that the continents were once distributed differently was geological evidence of glaciation in India – it is unlikely that glaciers could ever reach such low latitudes, but this problem can easily be explained by continental drift. Fossil distribution also provided some of the earliest evidence for plate tectonics – certain land-dwelling fossil species have been found in areas that are now separated by ocean which indicates that those areas were at some point joined together. However at the time of Wegner’s work many of the geophysical tools that are used today did not exist making the theory much...
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...Plate tectonics is the theory that explains the structure and motion of the Earth’s lithosphere. The theory states that the Earth’s crust is split into large sections called tectonic plates, and these move relative to one another creating boundaries at which plates converge, diverge and move past each other. Alfred Wegener pioneered the theory of continental drift in the early 1900s which he supported with multiple pieces of evidence. Perhaps the earliest indicator of the theory was the apparent fit of some of the Earth’s continents; analysis of these coastlines, notably the eastern edge of South America and the western edge of Africa, has shown that they are very similar geologically suggesting that at some point in the Earth’s history the landmasses were joined together. Another indicator that the continents were once distributed differently was geological evidence of glaciation in India – it is unlikely that glaciers could ever reach such low latitudes, but this problem can easily be explained by continental drift. Fossil distribution also provided some of the earliest evidence for plate tectonics – certain land-dwelling fossil species have been found in areas that are now separated by ocean which indicates that those areas were at some point joined together. However at the time of Wegner’s work many of the geophysical tools that are used today did not exist making the theory much more difficult to support. Paleomagnetism is one of the strongest pieces of evidence for plate...
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...Effects of the Motions of Tectonic Plates Worksheet From Visualizing Earth Science, by Merali, Z., and Skinner, B. J, 2009, Hoboken, NJ: Wiley. Copyright 2009 by Wiley. Adapted with permission. Part 1 This diagram was similar to one Alfred Wegener drew to show the distribution of continents 300 million years ago. His theory of continental drift was met with skepticism in the scientific community. [pic] 1. Describe three forms of evidence Wegener used to support his ideas of continental drift. Wegener used landorms, climate, and fossils to support his theory of continental drift. He said that when it came to landforms all the continents seemed to fit like a “jigsaw puzzle”. Even went as as far to say the mountain ranges seemed to line up as well. Wegener said that the same fossils and rock from one continent would end up on a different continent. For instance a fossil found in Africa would also be found in South America. When it came to climate, Wegener said that some fossils did not match the climate. For instance, there a glacier scratches in South Africa. 2. Years later, the continental drift theory reemerged as plate tectonic theory, with two additional pieces of evidence. [pic] [pic] Refer to the images above. Discuss in detail the two pieces of additional evidence that supported Wegener’s theory, now known as the theory of plate tectonics. The first image shows the...
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