New island emerges near Japan’s Ogasawara island chain after an undersea volcano erupted

A new island emerged near Japan’s Ogasawara island chain after an undersea volcano erupted late last month. Plumes of smoke and ash, reaching over 50 metres in height, were observed every few minutes during the eruptions which continued for about 10 days. The so far unnamed island is 100 metres in diametre and was formed by phreatomagmatic eruptions, which occur when magma interacts with seawater and produces an explosive burst of steam and ash.

Ogasawara Island chain, also known as Bonin Islands, is a volcanic arc comprising more than 30 islands and islets. Some of them are still active. Formation of the new island is a rare phenomenon with the last record of such volcanic activity in 2013. Japan has the most active volcanoes in the world at 111.