Magma accumulation highlights growing threat from Japanese volcano

A research team led by the University of Bristol has found magma build-up beneath Japan's Aira caldera and Sakurajima volcano may indicate a growing threat to Kagoshima city and its 600,000 inhabitants. The team was headed by Drs James Hickey and Joachim Gottsmann from the Volcanology Research Group at the School of Earth Sciences. They studied surface deformation in and around the caldera and volcano to characterise the magma supply conditions, and how they can be used for eruption forecasting and hazard assessment. The study, in collaboration with the Sakurajima Volcano Research Centre, is published today in Scientific Reports. Aira caldera is a large, submerged crater in the southern part of Kyushu, Japan, caused by the violent explosion and subsequent collapse of a voluminous magma reservoir. The re-growth of this magma storage zone has been feeding Sakurajima volcano, which is located on the southern rim of the caldera. Sakurajima is one of Japan's most active volcanoes with small, localised eruptions nearly every day, but the history of the volcano is even more ferocious.