seafloor spreading

American  

noun

1. 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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Etymology

Origin of seafloor spreading

First recorded in 1960–65

Example Sentences

Ship-based observations of the alternating magnetic “stripes” that result as slabs of ocean crust unfurl from the seafloor spreading centers helped give credence to the theory of plate tectonics in the 1960s.

From Science Magazine • Dec. 22, 2020

Dalton and her colleagues added to the picture by assembling a complementary high-resolution record for the Pacific Ocean, where seafloor spreading is faster and more complex.

From Science Magazine • Dec. 22, 2020

In 1959, Harry Hess proposed the hypothesis of seafloor spreading – that the mid-ocean ridges represented tectonic plate factories, where a new oceanic plate was issuing from these long volcanic ridges.

From Textbooks • Jan. 1, 2017

The evidence comes from seafloor spreading centers: sites throughout the ocean where plates of ocean crust move apart and magma erupts in between, building new crust onto the plates' trailing edges.

From Science Magazine • Feb. 5, 2015

It was equally dismissive of convection and seafloor spreading.

From "A Short History of Nearly Everything" by Bill Bryson