subduction zone: Quick Facts

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Cross-sectional diagram illustrating plate tectonics, showing oceanic and continental crust moving over the asthenosphere. It highlights divergent boundaries at oceanic ridges where crust forms, convergent boundaries at trenches with subduction zones where crust is destroyed, and a transform boundary with a fault. Features such as island arcs, rising magma, and hotspots are labeled.

The Earth's crust is a jigsaw puzzle of huge rigid plates in constant relative motion. The plates are bounded by three types of features: ridge axes, where new seafloor is created in mid-ocean; transform faults, where plates slide past one another; and subduction zones, where plates overlap, with one plate sliding under the other.

Diagram showing the process of slab pull in plate tectonics, with an oceanic plate subducting beneath a continental plate. Arrows illustrate mantle convection, gravity pulling the slab downward, and viscous resistance in the mantle layers, while labels identify the lithosphere, upper and lower mantle, and the forces acting on the plates.

cross section of a tectonic plate

Cross-sectional diagram of a subduction zone showing oceanic crust moving beneath continental crust, with features labeled including transform fault, oceanic ridge, trench, accretionary wedge, rising magma, and the Benioff-Wadati zone.

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