Report on Fukutoku-Oka-no-Ba (Japan) — October 1985
Scientific Event Alert Network Bulletin, vol. 10, no. 10 (October 1985)
Managing Editor: Lindsay McClelland.
Fukutoku-Oka-no-Ba (Japan) Discolored water
Please cite this report as:
Global Volcanism Program, 1985. Report on Fukutoku-Oka-no-Ba (Japan) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 10:10. Smithsonian Institution.
24.285°N, 141.481°E; summit elev. -29 m
All times are local (unless otherwise noted)
A milky white discoloration, about 100 m in diameter, was observed on 17 September and discoloration was noted again on 17 October.
Geologic Background. Fukutoku-Oka-no-ba is a submarine volcano located 5 km NE of the pyramidal island of Minami-Ioto. Water discoloration is frequently observed from the volcano, and several ephemeral islands have formed in the 20th century. The first of these formed Shin-Ioto ("New Sulfur Island") in 1904, and the most recent island was formed in 1986. The volcano is part of an elongated edifice with two major topographic highs trending NNW-SSE, and is a trachyandesitic volcano geochemically similar to Ioto.
Information Contacts: JMA, Tokyo.