seafloor spreading

noun

: the divergence at mid-ocean ridges of the tectonic plates underlying the oceans that is due to upwelling from the earth's interior of magma which solidifies and adds to the spreading plates

Examples of seafloor spreading in a Sentence

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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
As the land splits apart, the Afar Depression will sink deeper and deeper, a process known as seafloor spreading. — Ashley Stimpson, Popular Mechanics, 21 June 2023 The plan would take advantage of regions called subduction sinks, where sedimentary material is being drawn downward into the earth’s mantle as a consequence of seafloor spreading. — Mark Fischetti, Scientific American, 1 Feb. 2022

Word History

First Known Use

1969, in the meaning defined above

Time Traveler
The first known use of seafloor spreading was in 1969

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“Seafloor spreading.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/seafloor%20spreading. Accessed 10 Mar. 2025.

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