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Underwater Volcano Eruption

Facts for Prelims (FFP)


Source: TOI


Context: A new island has emerged near Japan’s Ogasawara island chain following an underwater volcano eruption in late October 2023.

  • The island formed through phreatomagmatic eruptions triggered by the interaction of magma with seawater.

What are phreatomagmatic eruptions?

 Phreatomagmatic eruptions are volcanic events triggered by the interaction of magma with water, typically seawater. These interactions lead to explosive releases of ash and steam. The term “phreatomagmatic” combines “phreatic,” relating to water, and “magmatic,” referring to magma. These eruptions often occur underwater and are characterized by the explosive nature of the ash and steam release.

About Japan’s Ogasawara island chain:

The chain, also known as the Bonin Islands, consists of over 30 islands and islets created by volcanic processes, including phreatomagmatic eruptions.