Continental Drift: What is it?Continental drift was originally a theory formed by Alfred Wegener in 1912, which states that all the landmasses on the planet was on one "super continent" known now as Pangaea, which was surrounded by Panthalassa (a global Ocean. His theory was that the Landmass broke apart and formed the continents today. Though this theory was harshly criticized (e.g., Dr. Chamberlain of University of Chicago), there was lots of evidence to back it up.
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For example, one piece of evidence was the continents fitting like puzzle pieces, similar landforms in different continents (e.g., Appalachian mountains in Europe), even finding resources like fuel and fossils not located in that area. There are also theory's about humans migrating across the Super continent when it was separating, causing there to be humans in other parts of there world, seeing that they were not intelligent enough to build boats.
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How depositation affects Earths landforms
Many thing affect the landforms which make up earths surface, like erosion which slowly chips away at rock until its completely reshaped, or weather, being a large contributor to erosion because of winds, rain and other natural causes. These are some of the well known ways to shape landforms, unlike deposition. Though not commonly known, deposition is a common thing all around the world, occurring in streams to rivers. Deposition is when water floods into a shallow area, known as a flood plain (land where water enters often). Every time it floods the water slowly chips at the surface, causing erosion.
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Human Land Reclamation
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In the video it the commentator said that the Honk Kong airport had narrowed down the options to just two, drained reclamation, and deep cement mixing. the drained reclamation method involves putting layers of earth and materials on the seabed, which creates pressure, then the water is extracted through wheepholes (steel tubes) and squeezes away the water. The issue was the water being squeezed out of the mud could be contaminated, which could hurt the underwater ecology. The second option, deep cement mixing, uses long drills to inject cement into the mud for a base. It has no impact to the environment whatsoever, and though considerably more expensive, In my opinion it was the better choice.
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