海水中のメタンを指標に用いた三宅島周辺海底における火山活動調査の結果について  [in Japanese] Geochemical Exploration of Volcanic Activity on the Sea Floor Using CH_4 as a Tracer : Miyakejima Volcano, Izu-Bonin Arc, Japan  [in Japanese]

In June 2000, several eruptions occurred on Miyake-jima Island, accompanied by volcanic and/or hydrothermal activity offshore from the island. In January 2001, water samples were collected from five stations around the island in order to reveal the existence of volcanic activity on the seafloor in the area. Concentrations and stable carbon isotopic compositions of dissolved methane in the water samples, however, showed no sign of submarine volcanic activity over the area. These results indicate that the submarine volcanic activity in the area was not in steady state at least during the sampling program.