Southeast Indian Ridge

oceanic ridge, Indian Ocean

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July 14, 2026

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The Southeast Indian Ridge is a significant underwater mountain chain in the Indian Ocean. It is part of the global oceanic ridge system, characterized by seismically active areas where new seafloor is created through seafloor spreading. This ridge extends eastward from near Madagascar until it connects with the Pacific-Antarctic Ridge south of Tasmania. Oceanic ridges are the largest features in ocean basins and form a vast network across the Earth's ocean floors. The Indian Ocean also features other submarine features like the aseismic Ninetyeast Ridge, which is the world's longest and straightest oceanic ridge.12

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oceanic ridge
Indian Ocean
The Southeast Indian Ridge spreads at intermediate rates. This ridge continues from the western Indian Ocean in a southeasterly direction, bisecting the ocean between Australia and Antarctica. Rifted crests and rugged mountainous flanks are characteristic of the Southwest Indian Ridge. The Mid-Indian Ridge has fewer features…
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The Southeast Indian Ridge spreads at intermediate rates. This ridge continues from the western Indian Ocean in a southeasterly direction, bisecting the ocean between Australia and Antarctica. Rifted crests and rugged mountainous flanks are characteristic of the Southwest Indian Ridge. The Mid-Indian Ridge has fewer features…
Read More