Pacific Plate

The Pacific Plate is a large oceanic tectonic plate beneath most of the Pacific Ocean. It moves generally northwest relative to surrounding plates and is bordered largely by subduction zones and spreading ridges.

Plate tectonics: The theory that Earth's lithosphere is divided into moving plates whose interactions shape the surface. The Pacific Plate is one of the largest moving pieces in this global system.
Oceanic crust: The thin, dense crust that forms the ocean floor, chiefly from basaltic rocks. The Pacific Plate consists predominantly of this crust.
Hawaiian–Emperor seamount chain: A chain of volcanoes and seamounts formed as the Pacific Plate moved over a long-lived mantle hotspot. Its age progression records the plate's changing direction and speed.
San Andreas Fault: A major transform fault in California separating the Pacific Plate from the North American Plate. It is a prominent example of lateral motion at the plate's boundary.
Pacific Ring of Fire: A belt of frequent earthquakes and volcanoes around the margins of the Pacific Ocean. Subduction around much of the plate's perimeter forms this active belt.
Lithosphere: Earth's rigid outer layer, comprising the crust and the uppermost mantle. The Pacific Plate is a moving section of this outer shell.
Hawaiian hotspot: A volcanic hotspot beneath the Pacific Plate that feeds the Hawaiian Islands and associated seamounts. The plate's motion over this hotspot built the Hawaiian–Emperor chain.
Aleutian Trench: A deep ocean trench formed where the Pacific Plate subducts beneath the North American Plate near Alaska. It marks a curved subduction boundary along the plate's northern margin.
Subduction: The descent of one tectonic plate beneath another into Earth's mantle. Much of the Pacific Plate's boundary is consumed where it descends beneath neighboring plates.
Asthenosphere: A hot, weak region of the upper mantle beneath the lithosphere that deforms over geological time. The plate moves over this underlying mantle layer.

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