An undersea volcanic eruption in the Tongan archipelago has sunk one island and created another one that is three times larger, according to a report by geologists released on Thursday.

Taaniela Kula, of the Tonga Geological Service, said the new island is estimated to be about 100 metres wide and 400 metres long, and is situated about 120 metres west of its now-submerged predecessor, Lateiki island.

The upheaval followed an 18-day undersea eruption last month in an area prone to earthquakes and volcanic activity.

The new island lies between Kao and Late in the Pacific island nation’s northern Ha’apai group of islands.

Tonga sits on the notorious Ring of Fire, an area of frequent seismic activity in the Pacific ocean and which is responsible for about 90% of the world’s earthquakes.

In late 2014 the eruption of an undersea volcano created another Tongan island that is now home to plants and birdlife.