a process in which new ocean floor is created as molten material from the earth's mantle rises in margins between plates or ridges and spreads out.
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British Dictionary definitions for sea-floor spreading
a series of processes in which new oceanic lithosphere is created at oceanic ridges, spreads away from the ridges, and returns to the earth's interior along subduction zones: Also called: ocean floor spreading
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for sea-floor spreading
In the theory of plate tectonics, the process by which new oceanic crust is formed by the convective upwelling of magma at mid-ocean ridges, resulting in the continuous lateral displacement of existing oceanic crust. See more at magnetic reversal.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Cultural definitions for sea floor spreading
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.