Macquarie Ridge

ridge, Pacific Ocean

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June 30, 2026

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The Macquarie Ridge is a significant underwater mountain range in the Pacific Ocean that forms a boundary between the Pacific and Indian Oceans. It extends southward from the Tasman Basin, located between New Zealand and eastern Australia. Macquarie Island, a volcanic landmass, is an exposed part of this ridge, situated where the Pacific and Indian-Australian plates meet. This geological activity results in earthquakes occurring approximately once a year. The island is recognized for being the only place globally where rocks from Earth's mantle are exposed above sea level.12

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Pacific Ocean
Principal ridges and basins
…and eastern Australia) is the Macquarie Ridge, which forms a major boundary between the deep waters of the Pacific and Indian oceans. The Hawaiian Ridge extends westward from Hawaii to the 180° meridian.
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…and eastern Australia) is the Macquarie Ridge, which forms a major boundary between the deep waters of the Pacific and Indian oceans. The Hawaiian Ridge extends westward from Hawaii to the 180° meridian.
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transform fault
…across a transform called the Macquarie Ridge. There subduction may be taking place at a slow rate.
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…across a transform called the Macquarie Ridge. There subduction may be taking place at a slow rate.
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