Mid-ocean ridge
<p>Jun 20, 2014 10:36 AM</p>
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underwater mountain system with a valley or rift running along its spine.</p>
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this is an oceanic spreading center and is respon for seafloor spreading.</p>
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magma rises up and emerges as lava which creates new crust...</p>
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this is divergent plate boundary.</p>
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like the seams of a baseball;</p>
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all mid-ocean ridges are connected... this is the longest mtn range in the world.
it is 50,000 miles long = 80K km.</p>
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see figure with "SLAB PULL" main mech of plate tectonics...</p>
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subducting lithosphere pulls seafloor along as it sinks.</p>
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also see magnetis striping (bands due to switches in earths mag field)
as crust spreads toward trenches.
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