Plate Tectonics and Landscape

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Chapter One
The theory of plate tectonics explains how forces within the planet create landforms. This theory views Earth’s crust as divided into more than a dozen, rigid, slow-moving plates. Some plates are as large as a quarter of the planet, but others are only a few hundred miles across. The plates slowly move across the upper mantle, usually less than an inch per year. Scientists use the theory of plate tectonics to explain the long history of Earth’s surface. They believe that about a few million years ago, all the continents that we have now today were part of one super continental called Pangaea. Pangaea then broke into two smaller supercontinents called Gandwana and Laurasia. These two then broke into the modern continents we have today. The theory of plate tectonics helps explain the fit between the African coastlines and South America. Rock formations that match up across boundaries provide more evidence. The theory also helps geographers understand the origins of mountains and the landforms of the ocean floor. The earth has a vast range of landscapes including the lay landscapes of Polar Regions, mountainous landscapes, densely forested or wooded landscapes including past bereal forests and tropical rainforests, and agricultural landscapes and tropical regions. My particular interest in this case study is to find out how these plate tectonics affect the landscapes of eastern Asia. I am also hoping to unravel the mystery behind what causes these movements of the plates in that particular area and whether the landscapes would be better or worse without these movements of the plates.

Chapter two
LITERATURE REVIEW AND DEFINITION OF CONCEPTS

PLATE TECTONICS
The German geologist and meteorologist Alfred Wegener hypothesized that there was an original, gigantic supercontinent 200 million years ago, which he named Pangaea, meaning "All-earth". Pangaea was a supercontinent consisting of all of Earth's land masses. It existed from the Permian through Jurassic periods. It began breaking up during the Jurassic period, forming continent Gondwanaland and Laurasia, separated by the Tethys Sea.

Wegener published this theory in his 1915 book, On the Origin of Continents and Oceans. In it he also proposed the existence of the supercontinent Pangaea, and named it (Pangaea means "all the land" in Greek). When geologists refer to plate tectonics as a theory, our attention is immediately shifted to all body of knowledge embodying the earths plates (meaning "plate structure") as was developed in the 1960's. This theory explains the movement of the Earth's plates (which has since been documented scientifically) and also explains the cause of earthquakes, volcanoes, oceanic trenches, mountain range formation, and many other geologic phenomenon. The top layer of the Earth's surface is called the crust (it lies on top of the plates) which solidified billions of years ago, and soon after the Earth formed. This crust is not a solid shell; it is broken up into huge, thick plates that drift atop the soft, underlying mantle. The oceanic crust (the thin crust under the oceans) is thinner and denser than continental crust. This crust is constantly being created and destroyed; oceanic crust is more active than continental crust The plates are made of rock and drift all over the globe. They move both horizontally (sideways) and vertically (up and down). Over long periods of time, the plates have also changed in size as their margins are added to, crushed together, or pushed back into the earth’s mantle. These plates are from 50 to 250 miles (80 to 400 km) thick. This causes the physical map of the earth to be continuously changing. Not only are the underlying plates moving, but the plates change in size. Also, the sea levels change over time (as the temperature on Earth changes and the poles melt or freeze to certain extents), covering or exposing different amounts of crust. The plates are moving at a speed that has been estimated...
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