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Report on Fukutoku-Oka-no-Ba (Japan) — September 1982

Scientific Event Alert Network Bulletin, vol. 7, no. 9 (September 1982)
Managing Editor: Lindsay McClelland.

Fukutoku-Oka-no-Ba (Japan) Discolored water observed on flights during December 1981-June 1982

Please cite this report as:

Global Volcanism Program, 1982. Report on Fukutoku-Oka-no-Ba (Japan). In: McClelland, L. (ed.), Scientific Event Alert Network Bulletin, 7:9. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198209-284130.

Volcano Profile |  Complete Bulletin


Fukutoku-Oka-no-Ba

Japan

24.285°N, 141.481°E; summit elev. -29 m

All times are local (unless otherwise noted)


JMSA [and JMSDF have] continued frequent monitoring flights over several known submarine volcanoes (table 1). On almost all overflights discolored sea water was seen around Fukutoku-Okanoba, the most active submarine volcano in this area.

Table 1. Volcanic activity at three sites (Fukutoku-Okanoba, Minami-Hiyoshi, and Fukujin) in the Volcano Islands, January 1978-December 1982, detected by JMSA and JMSDF monitoring flights. Activity indicated as D = Discolored water; N = No discolored water, - = No overflight, ? = not reported. This table combines data from reports in 1979 (4:7), 1980 (5:4, 5:11, and 5:12), 1981 (6:10), and 1982 (7:9, plus additional data not published in the Bulletin).

Date Fukutoku-Okanoba Minami-Hiyoshi Fukujin
10 Jan 1978 D N D
24 Jan 1978 D N D
25 Jan 1978 D - D
26 Jan 1978 - D D
23 Feb 1978 D D N
24 Mar 1978 D D D
13 Apr 1978 D N N
25 May 1978 D N N
28 Jun 1978 D - -
29 Jun 1978 D N N
25 Aug 1978 D N D
24 Oct 1978 N N N
15 Nov 1978 D - -
16 Nov 1978 D N N
14 Dec 1978 D N N
11 Jan 1979 D - -
24 Jan 1979 D N N
08 Feb 1979 D N N
27 Mar 1979 D [N] -
26 Apr 1979 D N D
15 Jun 1979 N N N
11 Jul 1979 N - -
12 Jul 1979 D N D
24 Aug 1979 N N -
09 Sep 1979 D - -
13 Sep 1979 D N N
25 Oct 1979 D N D
08 Nov 1979 D N D
12 Dec 1979 D N D
29 Jan 1980 - - D
15 Feb 1980 D N D
19 Mar 1980 D N D
24 Apr 1980 D N N
12 May 1980 D - D
16 Jun 1980 D N N
07 Jul 1980 D - -
08 Jul 1980 D N N
14 Jul 1980 D N N
18 Aug 1980 N N N
04 Sep 1980 N N N
21 Oct 1980 N N N
14 Nov 1980 D N N
18 Dec 1980 D N N
07 Jan 1981 - - D
08 Jan 1981 - - D
09 Jan 1981 D N N
29 Jan 1981 D - -
12 Feb 1981 D [-] -
20 Feb 1981 D [N] N
12 Mar 1981 D [-] -
13 Mar 1981 D N N
16 Mar 1981 D N N
20 Apr 1981 D N N
17 Jun 1981 N N N
16 Jul 1981 D - -
17 Jul 1981 D [N] [N]
22 Jul 1981 D N N
17 Aug 1981 D N N
17 Sep 1981 D N N
19 Oct 1981 N N N
11 Nov 1981 N N [-]
21 Dec 1981 D N N
12 Jan 1982 - - D
19 Jan 1982 D N D
09 Feb 1982 D N N
28 Feb 1982 D - -
16 Mar 1982 D N D
01 Apr 1982 D - N
02 Apr 1982 D N N
16 Apr 1982 D N N
14 May 1982 D N N
16 Jun 1982 D N N
22 Jun 1982 D - -
13 Jul 1982 D ? N
20 Aug 1982 D ? N
27 Sep 1982 D ? N
13 Oct 1982 D ? N
17 Nov 1982 D ? N
15 Dec 1982 D ? D

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.