Studying Plate Tectonics to Help in the Future Prior to World War II, humans were conformed with the idea that the Earth and its continents had been basically unchanged since the beginning of time. A German meteorologist, Alfred Wegener observed that the coastlines of the seven continents could be fitted together almost perfectly like a jigsaw puzzle. If fitted together, the geological dating the land would match as well as other geological features. He believed that this was more than coincidence, which happened to be the belief at the time. By putting all the continents together, he formed a large landmass that he named Pangea. This would also explain the same fossils found on 2 continents, separated by large oceans. Although the continents fit together nicely, and it would solve many of the earth's mysteries, people still rejected the idea that the continents moved for several reasons. Ignorance and strong religious beliefs played a part in this, but it was mainly rejected because of the lack of a good explanation for the movement of the continents. Wegener's theory for the movement of continents was called continental drift. This was not believable at the time because there was no way the continents could move through the rigid ocean floor. During WWII, people started to explore the ocean floor and discovered evidence that would prove Wegener's ideas about land movement. The most interesting feature of the ocean was the ridges running along the ocean floor. It was discovered that earthquakes were abundant along the ridges that let magma flow from them. The magma would flow out these ridges and push the Earth away from it. This sea floor spreading was how the continents had moved over millions of years. The earth's crust is in mobile sections called plates, moved by the circulation of magma in a layer of the earth called the mantle. The moving and colliding of plates form many of today's landforms such as the Himalayan Mountains. They were formed when India moved into Asia, colliding and making the shores of India go underneath Asia. Although we have found much on plate tectonics, there are still some unanswered questions. The depths of the plates are still unknown. Scientists are still unsure on how the motion of the mantle was initiated. There are many theories on how plate tectonics works and why the polarization of the Earth switches every million years but there have been no concrete facts.
15. The pictures above show how the continents on Earth’s surface have changed position over a very long period of time. What explains this change? (S6E5e, f)
Earthquakes are a natural part of the Earth’s evolution. Scientific evidence leads many geologists to believe that all of the land on Earth was at one point in time connected. Because of plate tectonic movements or earthquakes, continental drift occurred separating the one massive piece of land in to the seven major continents today. Further evidence supports this theory, starting with the Mid-Atlantic ridge, a large mass of plate tectonics, which are increasing the size of the Atlantic Ocean while shrinking the Pacific. Some scientists believe that the major plate moveme...
Source 4. A map of the Earth’s fault lines and plates with the direction of their movement.
Mignolo explained how America was incorporated into the continental triad cosmology created by the Christians. America was incorporated as a forth arm because the world was originally divided into three continents; Asia, Africa, and Europe (Mignolo, 2002, p. 23). The original map was called the “T-in-O” map compiled in the early seventh century (Mignolo, 2002, p. 24). America was not included in this map because the existence was still not heard of. This “T-in-O” map was created by Western Christians. The Western Christians drew their map as a circle and decided to divide the world in three parts. Only two parts of the circle were drawn equally. Asia covered the top half on the circle, which created a semi-circle. Europe then consisted of the bottom left quadrant in the circle, and then followed by Africa at the bottom right quadrant.
To set the stage, we must go back 270 million years ago when a majority of the earth’s land masses were collected together in a single continent, a supercontinent, named Pangaea (Encyclopedia Britannica, 1). Historian Alfred Crosby explained that this collected all of earth’s land based biology into a single place, creating a single Darwinian “arena for competition” (Crosby, 1). Or in other words, one big evolutionary pot. Crosby also explains that 180 million years ago, Pangea split into two major land masses, what is now the Americas in the Western Hemisphere as one land mass and Euro-Asia and Africa as the second lass mass (Crosby, 1). What was once a single evolutionary pot, was now two, allowing for plant and animal life to take different evolutionary paths. These two worlds remained relatively separate from each other until the arrival of Christopher Columbus and other European explorers. That contact between the old world and the new world brought two distinct evolutionary arenas crashing into each other and returned a majority of the earth’s landmass into a single Darwinian pot, (Crosby, 1) This was Crosby’s re-knitting of the torn “seams of Pangaea.”
Like the Arabs, the Europeans sometimes let their religion come between them and the truth. The best example of this is what Boorstin refers to as the “Great Interruption,” a time in the Middle Ages where theological, rather than geographical, accuracy was prioritized in mapmaking. Rather than continuing the work of Ptolemy and refining his rectangular coordinate system, cartographers “spent their energies embroidering a neat, theologically appealing picture of what was already known, or was supposed to be known.” (Boorstin, 100) Maps depicted the world as a circular disc divided into three parts, the three parts being the continents of Asia, Africa, and Europe, separated by a T-shaped flow of water. Jerusalem was always in the center of the maps; the justification came from a verse in Ezekiel saying that God had placed Jerusalem in the midst of the nations, which was interpreted literally. Allowing Christian dogma to determine the shape of the earth was a major failing in Boorstin’s eyes; nevertheless, the episode was only an “interruption,” and Europe eventually resumed discovery. Firstly, Boorstin credits the west for the modern clock and calendar. Although earlier versions of clocks from other parts of the world are mentioned, the author focuses primarily on the contributions of westerners to its development. When missionary
The traditional theory about the Earth’s core suggest that the core of the Earth is a solid nickel and iron sphere surrounded by a fluid metallic magma. The rotation of the Earth is believed to create massive columns of magma to swirl in the core. These columns are believed to produce the Earth’s magnetic field. This theory is based on the assumption that the Earth’s core is cooling and will eventually cool completely and cease to produce energy and a magnetic field. However, this theory does not answer many ongoing mysteries about the Earth, such as why the Earth’s magnetic field periodically shuts down, and questions about the energy production of the Earth. It was apparent that a new theory was needed to explain the mystery of the Earth’s core.
...s from the Paleozoic, Mesozoic, and Cenozoic periods show proof of how animals have gone through evolution and why certain fossils look very similar. The Law of Original Horizontality and the Law of Superposition both express true when looking at modern rock layers today. The Law of Original Horizontality happens when sediments are constantly deposited over old layers of rock forming new layers over millions of years, while the Law of Superposition is the law that older rock layers lie beneath the newer layers. Also, Pangea and Panthalassa are now the seven continents and four oceans of the world today as a result of Continental Drift. All things considered, Rock layers are therefore evidence of Evolution for, rock layers holds proof of evolving animals seen through fossils, the plates in the earth separated Pangea, and the relation of evolution and rock layers.
The rate of seafloor spreading was minimal during the Ordovician Period but thanks to high oceanic ridges, the seafloor became elevated and many parts of the continents were flooded. Shallow seas within the continents were thus formed. Sea levels fluctuated constantly maybe due to the rates of plate motion, ice caps, etc. The major tectonic plates were moving during this period so volcanism was extensive, peaking twice during the early Paleozoic Era. Mountain building belts were created wherever plates converged as well.
Since the beginning of human kind there has been a cloud of wonder of how our planet was formed. Scientist interested in this field through out the years have developed many different theories to how our planet came about. Before the Twentieth Century, scientists and geologists thought that mountain structures were due to the massive tightening of the earth caused by the gradual cooling of molten rocks. In 1900, American scientist Joseph Le Conte, published an article in the Appleton's Popular Scientific Monthly. He described that the problem in understanding mountain building was establishing the cause of sideways pressure. It was not until 1910, that an American Geologist named F.B.Taylor, proposed the idea of a continental drift. Other scientists dismissed Taylor's idea, because there was just not enough proof. However, Taylor's idea was then backed up by a German scientist named Alfred Wegener. He proposed that the continents surrounding the Atlantic Ocean, Africa and South America fit together like a jigsaw puzzle. His broad range of studies enabled him to incorporate his theory of Plate Tectonics. Wegener, later in 1915 while in the German military published his idea that interpreted how his continental drift theory worked. He proposed that a huge landmass called Pangea, meaning ("all land") existed 200 million years ago. He furthered explained that this super continent began to drift apart very slowly throughout millions of years into what it looks like now. Wegener went on several expeditions through out his life to the continents of South America and Africa.
First you might need to know definition of tectonics. It is a theory in geology. The lithosphere of the Earth is divided into a small number of plates which float on and travel independently over the mantle and much of the Earth’s seismic activity occurs at the boundaries of these plates. That is the official definition of Plate tectonics. secondly, this plate covers many parts of continents. plate boundaries don’t go according to Continents boundaries, they make their own boundaries. The North American plat...
Convection currents deep in the mantle of the earth, begin to well up towards the surface. As the pressure increases, it sets the crustal plates in motion. There are different kinds of mountains - Volcanic, Folded, Fault-block, and Dome mountains. Volcanic mountains are formed when magma comes up through cracks in the Earth’s crust and explodes out of lava and ash. The Hawaiian volcanoes, Mt. Hood, Mt. Etna, Vesuvius, and Mt. Saint Helens is an example of volcanic mountains.
Without studying plate tectonics, then we can never evaluate, prepare for, or predict: volcanic eruptions, earthquakes, or tsunamis. Without the theory of plate tectonics we would have never had known what the cause of earthquakes is or how to prepare for the arrival of an S-wave after the arrival of a P-wave. The theory of plate tectonics is not a lost cause or a finished theory. There is still a lot of progress to be made; right now my team and I are working on a way to predict earthquakes up to days in advance so that if the threat of a major earthquake is visible, we can evacuate before the P-wave even hits instead of panicking when the P-wave does hit. My team and I are also working on improved ways to predict and prepare for volcanic eruptions and tsunamis.
Convergent boundaries, divergent boundaries and convection currents all examples of physical evidence that supports the theory of plate tectonics. Continental drift is the theory contrived by Alfred Wegener in 1912 that states that Earth’s tectonic plates are in slow constant movement. At the time he didn’t know how the continents moved. The theory was soon modernized in the 50’s and the theory of plate tectonics became was born. Plate tectonics is the theory that tectonic plates are in slow constant movement due to convection currents in the mantle. Now we know for sure, thanks to scientific studies of convergent boundaries, divergent boundaries, and convection currents in the Earth’s mantle, that the continental drift and plate tectonics theories are not
The concurrent convective circulations in the mantle leads to some segments of the mantle moving on top of the outer core which is very hot and molten in nature. This kind of movement in different segments occurs as tectonic plates. These tectonic plates are basically seven on the earth surface as major ones, although, several small ones exist also. The plates motions are characterized by varying velocities, this variance results to sub sequential collision of two plates (leading to formation of a mountain in a convergent boundary), drift of two plates (leading to formation of rifts in a divergent boundary), or parallel movement in a transform boundary(Webcache 3).