PSNB+1.5

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=1.5 The Theory of Plate Tectonics=

Vocabulary

 * Plates:** Where the Lithosphere is broken into separate parts- called plates.
 * Scientific Theory:** A well tasted concept with lots of observation.
 * Plate Tectonics:** The theory which explains the Formation, movement, and subduction of the plates.
 * Faults:** Cracks in Earth's crust, where rocks have slipped past each other.
 * Transform Boundaries:** Where two plates have slipped past each other.
 * Divergent Boundaries:** Where two plates have moved apart from each other.
 * Convergent Boundaries:** Where two plates have moved into each other, or converged.
 * Rift Valley:** A deep valley that forms along convergent boundaries.

Outline
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 * ===Introduction===
 * Lithoshere is broken into pieces/sections seperated by jagged cracks, plates
 * J.Tuzo Wilson thought of concept
 * ===A theory of Plate Motion===
 * Plates are in constant slow motion driven by convection currents in mantle
 * Plate movements create volcanoes, mountain ranges, and deep-sea trenches
 * ===Plate Boundaries===
 * Lines where plates meet are plate boundaries
 * Faults are breads in earth's crust where rocks have slipped past each other
 * **Transform Boundaries**
 * Crust is neither created nor destroyed
 * Plates slip past each other going in opposite directions
 * Earthquakes occur frequently here
 * **Divergent Boundaries**
 * Plates move apart, usually occurs in mid-ocean ridge, also on land
 * On land, it creates a rift valley, going deeper and deeper into crust
 * Rift valley will someday drop enough for the sea to come in and fill the gap, seperating the land
 * **Convergent Boundaries**
 * Plates collide/come together, may bring together oceanic with oceanic, continental with continental, or oceanic with continental crusts.
 * The denser plate dives under the less dense plate (oceanic goes under continental, for oeanic and oceanic the density decides)
 * Continental and continental usually have same density, so they keep squeezing to make mountains
 * ===The Continents Slow Dance===
 * Plates move from one to ten centimeters per year, as fast as fingernails grow
 * Pangea is true, now scientists support the theory