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Plate Tectonics: it is the theory that explains how the continents move and how it is the study of the formation of the features in earth's crust.
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Continental Drift: it is the hypothesis that states that the continents once formed a single landmass, broken, and drifted to their present locations.
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Pangaea; it is the super continent that formed 300 million years ago and that began to break up beginning 250 million years ago.
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Asthenosphere: it is the solid,plastic layer of the mantle beneath the lithosphere; made of mantle rock that flows very slowly,which allows tectonic plates to move on top of it.
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Lithosphere: it is the solid,outer layer of the earth that consist of the crust and the rigid upper part of the mantle.
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Mid-ocean ridge: it is a long, undersea mountain chain that has a steep, narrow valley at its center, that forms as magma rises from the asthenosphere , and that creates new oceanic lithosphere (sea floor) as tectonic plates moves apart.
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Rift valleys: an elongated valley formed by the depression of a block of the earth's crust between two faults or groups of faults of approximately parallel orientation.
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Subduction: it is the region along a plate boundary where one plate moves under another plate.