9781422269534

Big Bend National Park is in the Basin and Range province and is another example of a divergent boundary which covers a vast area from southern Idaho to Sonora, Mexico and includes parts of California and Utah as well. The Earth's crust has been stretched up to 100% of its original width, creating large faults and carving out valleys.

Tectonic Plates The earth has seven major tectonic plates that fit together like a jigsaw puzzle. What exactly is a tectonic plate? It is a large rigid piece of the Earth’s lithosphere. The plates constantly move and interact with each other, and that movement results in various geological events, including the formation of mountain ranges, volcanic activity, and earthquakes. The seven plates are the African Plate, Antarctic Plate, Eurasian Plate, Indo-Australian Plate, North American Plate, Pacific Plate, and South American Plate. The plates are named after the continents or oceans they cover. What causes the tectonic plates to move? The asthenosphere is a partially molten layer of the Earth’s mantle. Currents occur in

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Facing the Weather: Earthquakes