seafloor spreading


Definition of seafloor spreading

: 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

Recent Examples on the Web Instead, they are forged through what Sager refers to as an augmented type of seafloor spreading. Robin George Andrews, National Geographic, "This is now the world's largest volcano, geologists say," 15 July 2019 Even after the seafloor spreading discovery, some Expanding Earth scientists stuck to their guns. Meg Neal, Popular Mechanics, "We’ve Been Wrong Before: The Expanding Earth Theory," 3 Aug. 2018 Soon after, an explosion in oceanic exploration helped flesh out the theory of seafloor spreading, eventually leading to the landmark 1963 paper that vindicated Wegener's original theory—with one major adjustment. Matt Blitz, Popular Mechanics, "How GPS Changed the Way We Think About Our Planet," 18 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'seafloor spreading.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of seafloor spreading

1969, in the meaning defined above

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The first known use of seafloor spreading was in 1969

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Cite this Entry

“Seafloor spreading.” Dictionary, Merriam-Webster, Accessed 29 Oct. 2020.

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