- a curved chain of islands, as the Aleutians or Antilles, usually convex toward the ocean and enclosing a deep-sea basin.
Origin of island arc
First recorded in 1905–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- an arc-shaped chain of islands, such as the Aleutian Islands or the Japanese Islands, usually lying at the edge of a Benioff zone, indicating volcanic activity where the oceanic lithosphere is descending into the earth's interior
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A usually curved chain of volcanic islands bounded on the convex side by a deep oceanic trench. Island arcs form in the overriding tectonic plates of subduction zones as the result of rising melt from the downgoing plate. The arcs are curved because of the curvature of the Earth. The Aleutian Islands, in Alaska, are an island arc. An island arc is a kind of volcanic arc.
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