Kikai Caldera

The Kikai Caldera extends 19 kilometers in diameter beneath the waters of the Osumi Strait, reaching a height of 704 meters above sea level.

The caldera formed through multiple volcanic events, with its most recent major eruption occurring 7,300 years ago, producing extensive pyroclastic flows across southern Japan.

The Kikai-Akahoya eruption transformed the Jomon period settlements in southern Kyushu, leading to widespread demographic changes in prehistoric Japanese communities.

Scientists monitor the underwater caldera continuously through seismic stations and gas emission measurements at Mount Io, an active volcanic vent within the structure.

The caldera contains a central post-eruption lava dome that releases hydrothermal plumes, indicating ongoing magmatic activity beneath the ocean surface.

Location: Kagoshima Prefecture

Elevation above the sea: 704 m

GPS coordinates: 30.78900,130.30800

Latest update: May 26, 2025 19:19