THEY+1.5

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=1.5 The Theory Of Plate Tectonics=

Vocabulary

 * Plates**: A section of the lithosphere that slowly moves over the asthenosphere
 * Scientific Theory**: A well tested concept that explains a Plate Tectonics
 * Plate Tectonics**: The theory that pieces of Earth's lithosphere are in constant motion
 * Faults**: A break in the Earth's crust were rocks slip past each other
 * Transform Boundary**: A plate boundary were the plates slip past each other in opposite directions
 * Divergent Boundary**: A plate boundary were the plates move away from each other
 * Rift Valley**: A deep valley were two plates move apart
 * Convergent Boundary**: A plate boundary where two plates move into each other

A Theory of Plate Motion

 * This theory explains the formation, movement, and subduction
 * Convection currents rise in the asthenosphere with the lithosphere

Plate Boundaries

 * The edges of different pieces of the lithosphere, Earth's rigid shell meets lines called Boundaries
 * Faults are the break in the Earth's Crust

Transform Boundary

 * The meaning of transform boundary is when the two plates move past each other in opposite directions
 * Earthquakes occur with transform boundaries

Divergent Boundaries

 * The places where the two plates diverge is called divergent boundary
 * Most divergent boundaries occur at the Mid-Ocean Ridge
 * A Deep valley is called a Rift Valley
 * Rift Valleys form along different boundaries

Convergent Boundaries

 * The place where two plates converge is called convergent boundary
 * When the plates converge they form mountains
 * Collision may bring together continental crust & oceanic crust

The Continents' Slow Dance

 * The plates move in at an amazingly slow rate (from about one to ten centimeter per year)
 * About 260 years ago the continents were all together and it formed Pangaea