Tectonic Plates

The Pacific Plate is an oceanic tectonic plate beneath the Pacific Ocean.

To the north the easterly side is a divergent boundary with the Explorer Plate, the Juan de Fuca Plate and the Gorda Plate forming respectively the Explorer Ridge, the Juan de Fuca Ridge and the Gorda Ridge. In the middle the easterly side is a transform boundary with the North American Plate along the San Andreas Fault and a boundary with the Cocos Plate. To the south the easterly side is a divergent boundary with the Nazca Plate forming the East Pacific Rise.

The southerly side is a divergent boundary with the Antarctic Plate forming the Pacific-Antarctic Ridge.

The westerly side is a convergent boundary subducting under the Eurasian Plate to the north and the Philippine Plate in the middle forming the Mariana Trench. In the south, the Pacific Plate has a complex but generally convergent boundary with the Indo-Australian Plate, subducting under it north of New Zealand forming the Tonga Trench and the Kermadec Trench. The Alpine Fault marks a transform boundary between the two plates, and further south the Indo-Australian Plate subducts under the Pacific Plate forming the Puysegur Trench. The part of Zealandia to the east of this boundary is the plate's largest block of continental crust.

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Most of information derived from Wikipedia