Pacific Plate

What happens at its edges

Its edges make up most of the Pacific Ring of Fire. Along its western and northern sides it sinks beneath its neighbors in deep trenches, from Tonga and the Kermadecs to Japan, the Kuril Islands, Kamchatka and the Aleutians, which is why those coasts have frequent large earthquakes and long chains of volcanoes.

In California it meets the North American Plate side-on: the two slide past each other along the San Andreas Fault system rather than one sinking beneath the other. In the southeast it spreads away from the Nazca and Cocos plates along the East Pacific Rise, one of the fastest-spreading ridges on Earth.

The Hawaiian Islands formed as the plate moved over a hotspot in the mantle. The islands get older toward the northwest, the direction the plate is moving.

How fast it moves, and which way

At its center (1.6°N, 157.3°W) the Pacific Plate moves about 7.2 cm (2.8 in) a year toward the west-northwest. Because a plate turns around a pole rather than sliding in a straight line, the speed changes across it: from 3.0 cm (1.2 in) a year to 7.2 cm (2.8 in) a year, with an area-weighted average of 6.5 cm a year. That average makes it the 11th fastest of the 52 plates.

These figures are measured against the average motion of all the plates together (the “no-net-rotation” frame), which is how plate speeds are usually quoted. Measured against the North American Plate instead, the Pacific Plate moves about 8.2 cm (3.2 in) a year toward the northwest at its center.

In the model it rotates about a pole at 63.2°S, 107.7°E at 0.649° per million years. The speeds are averages over years to millions of years of measurement; earthquakes move the ground near a boundary in sudden steps instead.

Neighboring plates and boundaries

Its edges run for 48,330 km (30,030 mi): 40% convergent, where plates move together; 31% divergent, where they move apart; and 28% transform, where they slide past each other. It sinks beneath the North American Plate, Okhotsk Plate, Kermadec Plate, Mariana Plate, Philippine Sea Plate and Tonga Plate at subduction zones. The Australian Plate and Woodlark Plate sink beneath it.

Relative speed is how fast the two plates move against each other along their shared edge, averaged over its length.

Countries and territories on the Pacific Plate

12 lie entirely on it; the other 7 are split between plates. The share is the part of each country’s land on this plate.

• Mexico about 7%
• New Zealand about 44%
• United States about 1%
• Solomon Islands about 98%
• Papua New Guinea about 2%
• French Polynesia all
• Samoa all
• Kiribati all
• Federated States of Micronesia about 85%
• Niue all
• Cook Islands all
• American Samoa all
• Marshall Islands all
• Wallis and Futuna all
• Pitcairn Islands all
• Nauru all
• United States Minor Outlying Islands about 83%
• Tuvalu all
• Clipperton Island all

Volcanoes on the Pacific Plate

The Smithsonian Global Volcanism Program lists 43 volcanoes on this plate that have been active in roughly the past 12,000 years. The most recent eruptions on record:

• Bagana Papua New Guinea, 2026
• Kilauea United States, 2026
• Northern EPR at 9.8°N Seafloor, 2025
• Tinakula Solomon Islands, 2024
• Mauna Loa United States, 2022
• Kavachi Solomon Islands, 2014

Where the edges are blurred

Parts of this plate lie in the New Hebrides-Fiji zone, which the model marks as broad belts of deformation rather than sharp plate edges. There the motion between plates is spread over many faults, and a single boundary line is a simplification.

Sources

Outline, area, boundary types and motion: Bird, P. (2003), An updated digital model of plate boundaries, Geochemistry Geophysics Geosystems, 4(3), 1027, doi:10.1029/2001GC000252. Released by its author into the public domain (CC0 1.0). Areas are the model’s published figures; speeds, directions, boundary lengths and countries are calculated from its outlines, boundary steps and rotation poles.

Volcanoes: Global Volcanism Program, Smithsonian Institution, Volcanoes of the World (v. 5.4.0). Country outlines: Natural Earth.