subduction

American  

[suhb-duhk-shuhn] / səbˈdʌk ʃən /

noun

1. an act or instance of subducting; subtraction or withdrawal.

2. Geology. the process by which collision of the earth's crustal plates results in one plate's being drawn down or overridden by another, localized along the juncture subduction zone of two plates.

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subduction British  

/ səbˈdʌkʃən /

noun

1. the act of subducting, esp of turning the eye downwards

2. geology the process of one tectonic plate sliding under another, resulting in tensions and faulting in the earth's crust, with earthquakes and volcanic eruptions

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subduction Scientific  

/ səb-dŭk′shən /

1. A geologic process in which one edge of one lithospheric plate is forced below the edge of another. The denser of the two plates sinks beneath the other. As it descends, the plate often generates seismic and volcanic activity (from melting and upward migration of magma) in the overriding plate.

2. Compare obduction

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Etymology

Origin of subduction

1570–80; < Latin subductiōn-, stem of subductiō pulling up, computation; subduct, -ion

Example Sentences

Transform boundaries -- the faults where plates slide past each other -- act like natural scissors, slicing across the plate and isolating fragments that form new microplates while subduction continues nearby.

From Science Daily • Oct. 25, 2025

When the massive subduction zone lying under the Pacific Northwest shifts, it does so violently.

From Science Daily • Oct. 22, 2025

North of Cape Mendocino, California, the Juan de Fuca plate dives beneath North America along a megathrust subduction zone known as Cascadia.

From Science Daily • Oct. 22, 2025

New research offers the theory that the San Andreas fault and the Cascadia subduction zone could produce devastating back-to-back earthquake disasters.

From Los Angeles Times • Oct. 15, 2025

There, the Pacific Plate slides beneath the North American Plate in what’s known as a subduction fault.

From "Meltdown" by Deirdre Langeland