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September 12, 2016

It’s not flirting for submarines, but this week’s EarthWord does feature the ocean...

EarthWords is an on-going series in which we shed some light on the complicated, often difficult-to-pronounce language of science. Think of us as your terminology tour-guides, and meet us back here every week for a new word!

A figure showing the oceanic plate sliding beneath the continental plate. Credit: USGS

The EarthWord: Subduction


  • No, this isn’t how submarines flirt, but it does involve the ocean. Subduction occurs when an oceanic plate runs into a continental plate and slides beneath it.


  • Subduction comes from the Latin subductionem, which meant “a withdrawal” or “hauling ashore.”

Use/Significance in the Earth Science Community:

  • Subduction is one of the several ways that tectonic plates interact with each other. Since each interaction can produce natural hazards like earthquakes, tsunamis, volcanoes, and landslides, understanding each type of interaction is important.

  • Subduction zones, since they involve oceanic plates, are known for earthquakes that produce tsunamis and are often responsible for volcanic ranges too.


  • USGS studies natural hazards associated with subduction zones as part of our Natural Hazards Mission Area.

  • The primary subduction zone we study is the Cascadia Subduction Zone, where the Juan de Fuca Plate is sliding beneath the North American Plate. That subduction zone is largely responsible for the Cascade Volcanic Range, as well as significant earthquake and tsunami hazard for the Pacific Northwest.

  • In addition, USGS studies natural hazard risk at the subduction zone where the Pacific Plate is sliding underneath the North American Plate along the Aleutian Islands and Coastal Alaska.

Next EarthWord: It’s what all these tectonic plates make up...

Hungry for some science, but you don’t have time for a full-course research plate? Then check out USGS Science Snippets, our snack-sized science series that focuses on the fun, weird, and fascinating stories of USGS science.