How much volcanic activity happens underwater?

From Dr. Samuel J. Mitchell’s Garden Talk “What secrets do volcanoes hide?
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Approximately 70-80% of Earth's volcanoes are located underwater, primarily in the Pacific Ocean near the edges of tectonic plates. This is roughly inline with the percentage of the Earth that is covered in water. These underwater volcanoes are formed when magma rises up from deep within the Earth and erupts on the ocean floor. The magma solidifies and forms a volcano, which can build up over time to create an island or seamount. Underwater volcanoes are often less explosive than those on land. The deepest volcanic activity that has been discovered is approximately 5-6km deep, but know every little about volcanic activity below this depth.

Learn more about this with our series “Inner Earth”

From secret worlds to mystical doors, subterranean land appeared in ancient mythology, and legends in all kinds of flavours. But right under our feet lies an incredible force of nature capable of keeping us alive as well as posing existential threats

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