Minami-Hiyoshi

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  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 23.5°N
  • 141.935°E

  • -107 m
    -351 ft

  • 284131
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Bulletin Report: January 1996 (BGVN 21:01)


Discolored seawater plume 6 km long

On 12 January, an aviator from the JMSA observed seawater discolored to yellowish green in an area 500 m wide and 6 km long, flowing from Minami-Hiyoshi seamount to the S. Discolored water was last observed in February 1992 (BGVN 17:02).

Periodic water discoloration and water-spouting has been reported over this submarine volcano since 1975, when detonations and an explosion were also reported. Located 90 km SE of Minami-Iwo-Jima, Minami-Hiyoshi lies near the SE end of a coalescing chain of youthful seamounts, and is the only historically active vent. The morphologically youthful seamounts Kita-Hiyoshi and Naka-Hiyoshi lie to the NW, and Ko-Hiyoshi to the SE.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.

The Global Volcanism Program has no Weekly Reports available for Minami-Hiyoshi.

Index of Bulletin Reports


Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

01/1977 (NSEB 02:01) Bubbling water and discoloration

02/1977 (NSEB 02:02) Two zones of discolored water observed from the air

04/1977 (NSEB 02:04) Zone of discolored water seen on 27-28 March

05/1978 (SEAN 03:05) Green discolored water seen on 10 January

07/1979 (SEAN 04:07) Discolored water seen during January-March 1978

04/1980 (SEAN 05:04) No water discoloration seen since March 1978

11/1980 (SEAN 05:11) No observed activity since March 1978

12/1980 (SEAN 05:12) No seawater discoloration seen in November-December 1980

10/1981 (SEAN 06:10) No discolored water seen during January-October 1981

09/1982 (SEAN 07:09) No water discoloration seen since March 1978

03/1984 (SEAN 09:03) No water discoloration seen since March 1978

12/1990 (BGVN 15:12) No water discoloration seen in 1990

02/1992 (BGVN 17:02) Discolored water

01/1996 (BGVN 21:01) Discolored seawater plume 6 km long




Bulletin Reports

All information contained in these reports is preliminary and subject to change.


01/1977 (NSEB 02:01) Bubbling water and discoloration

The crew of a JMSA aircraft recently observed that bubbling water near Minami Iwo-Jima had changed to an ashen brown color. Orange and yellow flotsam was seen in the area. [The location given for this observation was 23.48°N, 141.67°E, or 90 km SSE of Fukutoku-okanoba, in the vicinity of Minami-Hiyoshi seamount.] Activity was reported nearby (23.50°N, 141.92°E) in August 1975.

Information Contacts: AFP; U.S. Defense Mapping Agency.

02/1977 (NSEB 02:02) Two zones of discolored water observed from the air

On 10 January, a JMSA aircraft noted two adjacent zones of discolored water. One zone was 5.5 x l km, colored gray and milky white at the center. Each color was thought to have been generated by a separate vent. The second zone, 6.5 km long, was pale green to yellowish-brown. No volcanic ejecta were observed. By 24 January, activity had decreased markedly. Depth at the site is reported to be 130 m.

Information Contacts: JMA, Tokyo; Japanese Press.

04/1977 (NSEB 02:04) Zone of discolored water seen on 27-28 March

A discolored belt was observed on the sea surface at this site on 27 and 28 March. Similar activity had been reported at Minami-Hiyoshi beginning 10 January, but had declined by 24 January.

[The JMA provided additional chronological information on the 1977 discolorations. They were observed by the crew of JMSA aircraft on 10-14, 17-18, 21, 26, and 28-29 January, and 3-4, 11, 18, and 24-25 February. JMSDF crews continued to see them on 10, 11, and 17 March, but saw no discolorations on 18, 19, 21, 23, and 25 March. Discolorations were again visible on the next 3 days (26-28 March) during JMSDF flights, but were not seen on 6 April by a JMSA flight nor by any subsequent flights that year.]

Information Contacts: JMA, Tokyo.

05/1978 (SEAN 03:05) Green discolored water seen on 10 January

Four areas of pale green discolored water were observed on 10 January. [JMA has added the information that JMSA flight crews on 10 and 24 January saw no discoloration, but it was seen on 26 January and again on both 23 February and 24 March by JMSDF aircraft personnel. As noted in the long tables above under Fukutoku-okanoba, discoloration was not seen on 13 April or on any subsequent flights.]

Information Contacts: JMA, Tokyo.

07/1979 (SEAN 04:07) Discolored water seen during January-March 1978

Minami-hiyoshi, formerly named Hiyoshi-oki-no-ba, was active January-March 1977 and January-March 1978. [Discolored water was specifically noted, in an included table of observations during January 1978-July 1979, on 26 January, 23 February, and 24 March 1978.]

Information Contacts: JMA, Tokyo.

04/1980 (SEAN 05:04) No water discoloration seen since March 1978

The Japan Maritime Safety Agency continues frequent monitoring flights over three known submarine volcanoes. [Discolored water at Minami-hiyoshi was not seen during August 1979-March 1980 (see table 1 below).]

Information Contacts: JMSA, Tokyo; JMA, Tokyo.

11/1980 (SEAN 05:11) No observed activity since March 1978

The Japan Maritime Safety Agency (JMSA) continues frequent monitoring flights over several known submarine volcanoes. [Discolored water at Minami-hiyoshi was not seen during April-October 1980 (see table 1 below).]

Information Contacts: JMSA, Tokyo; JMA, Tokyo.

12/1980 (SEAN 05:12) No seawater discoloration seen in November-December 1980

The Japanese Maritime Safety Agency (JMSA) continues frequent aerial monitoring of several known submarine volcanoes. [Discolored water was not seen at Minami-hiyoshi during November-December 1980 (see table 1 below).]

Information Contacts: JMSA, Tokyo; JMA, Tokyo.

10/1981 (SEAN 06:10) No discolored water seen during January-October 1981

The Japan Maritime Safety Agency (JMSA) continues frequent monitoring flights over several known submarine volcanoes. [No discolored water was specifically noted, in an included table of observations, during January-October 1981 (see table 1 below).]

Information Contacts: JMSA, Tokyo; JMA, Tokyo.

09/1982 (SEAN 07:09) No water discoloration seen since March 1978

JMSA [and JMSDF have] continued frequent monitoring flights over several known submarine volcanoes (table 1). No discolored sea water has been observed near Minami-Hiyoshi since March 1978.

Table 1. Volcanic activity at three sites 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 4:7, 5:4, 5:11, 5:12, 6:10, and 7:9, plus additional 1982 data not published in the Bulletin.

    Date         Fukutoku-okanoba    Minami-Hiyoshi    Fukujin

    10 Jan 78           D                  N               D
    24 Jan 78           D                  N               D
    25 Jan 78           D                  -               D
    26 Jan 78           -                  D               D
    23 Feb 78           D                  D               N
    24 Mar 78           D                  D               D
    13 Apr 78           D                  N               N
    25 May 78           D                  N               N
    28 Jun 78           D                  -               -
    29 Jun 78           D                  N               N
    25 Aug 78           D                  N               D
    24 Oct 78           N                  N               N
    15 Nov 78           D                  -               -
    16 Nov 78           D                  N               N
    14 Dec 78           D                  N               N

    11 Jan 79           D                  -               -
    24 Jan 79           D                  N               N
    08 Feb 79           D                  N               N
    27 Mar 79           D                 [N]              -
    26 Apr 79           D                  N               D
    15 Jun 79           N                  N               N
    11 Jul 79           N                  -               -
    12 Jul 79           D                  N               D
    24 Aug 79           N                  N               -
    09 Sep 79           D                  -               -
    13 Sep 79           D                  N               N
    25 Oct 79           D                  N               D
    08 Nov 79           D                  N               D
    12 Dec 79           D                  N               D

    29 Jan 80           -                  -               D
    15 Feb 80           D                  N               D
    19 Mar 80           D                  N               D
    24 Apr 80           D                  N               N
    12 May 80           D                  -               D
    16 Jun 80           D                  N               N
    07 Jul 80           D                  -               -
    08 Jul 80           D                  N               N
    14 Jul 80           D                  N               N
    18 Aug 80           N                  N               N
    04 Sep 80           N                  N               N
    21 Oct 80           N                  N               N
    14 Nov 80           D                  N               N
    18 Dec 80           D                  N               N

    07 Jan 81           -                  -               D
    08 Jan 81           -                  -               D
    09 Jan 81           D                  N               N
    29 Jan 81           D                  -               -
    12 Feb 81           D                 [-]              -
    20 Feb 81           D                 [N]              N
    12 Mar 81           D                 [-]              -
    13 Mar 81           D                  N               N
    16 Mar 81           D                  N               N
    20 Apr 81           D                  N               N
    17 Jun 81           N                  N               N
    16 Jul 81           D                  -               -
    17 Jul 81           D                 [N]             [N]
    22 Jul 81           D                  N               N
    17 Aug 81           D                  N               N
    17 Sep 81           D                  N               N
    19 Oct 81           N                  N               N
    11 Nov 81           N                  N              [-]
    21 Dec 81           D                  N               N

    12 Jan 82           -                  -               D
    19 Jan 82           D                  N               D
    09 Feb 82           D                  N               N
    28 Feb 82           D                  -               -
    16 Mar 82           D                  N               D
    01 Apr 82           D                  -               N
    02 Apr 82           D                  N               N
    16 Apr 82           D                  N               N
    14 May 82           D                  N               N
    16 Jun 82           D                  N               N
    22 Jun 82           D                  -               -
    13 Jul 82           D                  ?               N
    20 Aug 82           D                  ?               N
    27 Sep 82           D                  ?               N
    13 Oct 82           D                  ?               N
    17 Nov 82           D                  ?               N
    15 Dec 82           D                  ?               D

Information Contacts: JMSA, Tokyo; JMA, Tokyo.

03/1984 (SEAN 09:03) No water discoloration seen since March 1978

Frequent monitoring of several known submarine volcanoes has continued. . . . Minami-Hiyoshi produced discolored sea water January-March 1977 and January-March 1978 but no further activity has been observed.

Information Contacts: JMA, Tokyo.

12/1990 (BGVN 15:12) No water discoloration seen in 1990

No discolorations were observed at . . . Minami-Hiyoshi . . . during 1990.

Information Contacts: Hydrographic Department, JMSA.

02/1992 (BGVN 17:02) Discolored water

An area of green discolored water, 3-5 km long, was observed over the volcano during an overflight on 12 February. Subsequent overflights revealed additional water discolorations on 28 February, and 2, 3, and 4 March, although no discoloration was seen on 21 February. The 4 March discoloration appeared to have a source area 100 m across. Overflights have been conducted almost every month in the Izu and Volcano Islands by the JMSA. This was the first observed incidence of water discoloration since the mid-to-late 1970's, when bubbling, spouting, and discolored water were occasionally sighted.

Information Contacts: JMSA.

01/1996 (BGVN 21:01) Discolored seawater plume 6 km long

On 12 January, an aviator from the JMSA observed seawater discolored to yellowish green in an area 500 m wide and 6 km long, flowing from Minami-Hiyoshi seamount to the S. Discolored water was last observed in February 1992 (BGVN 17:02).

Periodic water discoloration and water-spouting has been reported over this submarine volcano since 1975, when detonations and an explosion were also reported. Located 90 km SE of Minami-Iwo-Jima, Minami-Hiyoshi lies near the SE end of a coalescing chain of youthful seamounts, and is the only historically active vent. The morphologically youthful seamounts Kita-Hiyoshi and Naka-Hiyoshi lie to the NW, and Ko-Hiyoshi to the SE.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.

Periodic water discoloration and water-spouting have been reported over this submarine volcano since 1975, when detonations and an explosion were also reported. It lies near the SE end of a coalescing chain of youthful seamounts, and is the only historically active vent. The reported depth of the summit of the trachyandesitic volcano has varied between 274 and 30 m. The morphologically youthful seamounts Kita-Hiyoshi and Naka-Hiyoshi lie to the NW, and Ko-Hiyoshi to the SE.

Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1996 Jan 11 ] [ 1996 Jan 12 ] Uncertain 0  
[ 1992 Feb 12 ] [ 1992 Mar 4 ] Uncertain 0  
[ 1978 Jan 26 (?) ] [ 1978 Mar 24 ] Uncertain 0  
[ 1976 Dec 20 ] [ 1977 Mar 28 ] Uncertain 0   Hiyoshi-Okinoba (also 23.48 N 141.67 E)
[ 1976 Feb ] [ Unknown ] Uncertain 0  
1975 Aug 25 Unknown Confirmed 0 Historical Observations 23.50 N 141.92 E

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.


Synonyms

Hiyoshi-okinoba | Hiyosi-okinoba | Minami-Hiyoshi Kaizan

Craters

Feature Name Feature Type Elevation Latitude Longitude
Kita-Hiyoshi Submarine crater
Ko-Hiyoshi Submarine crater
Naka-Hiyoshi Submarine crater
Minami-Hiyoshi submarine volcano (center) is seen in this Japan Coast Guard bathymetric image with north to the right. Periodic water discoloration and water-spouting have been reported over this submarine volcano since 1975, when detonations and an explosion were also reported. Minami-Hiyoshi lies near the SE end of a coalescing chain of youthful seamounts and is the only historically active vent. The morphologically youthful seamount Naka-Hiyoshi (upper right) lies to the NW and Ko-Hiyoshi seamount (left) to the SSE.

Image courtesy of HOD Japan Coast Guard (http://www1.kaiho.mlit.go.jp/jhd-E).

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.

Bloomer S H, Stern R J, Smoot N C, 1989. Physical volcanology of the submarine Mariana and Volcano arcs. Bull Volc, 51: 210-224.

Japan Meteorological Agency, 1996. National Catalogue of the Active Volcanoes in Japan (second edition). Tokyo: Japan Meteorological Agency, 502 p (in Japanese).

Japan Meteorological Agency, 2013. National Catalogue of the Active Volcanoes in Japan (fourth edition, English version). Japan Meteorological Agency.

Kudo T, Hoshizumi H, 2006-. Catalog of eruptive events within the last 10,000 years in Japan, database of Japanese active volcanoes. Geol Surv Japan, AIST, http://riodb02.ibase.aist.go.jp/db099/eruption/index.html.

Nakano S, Yamamoto T, Iwaya T, Itoh J, Takada A, 2001-. Quaternary Volcanoes of Japan. Geol Surv Japan, AIST, http://www.aist.go.jp/RIODB/strata/VOL_JP/.

Smithsonian Institution-SEAN, 1975-89. [Monthly event reports]. Bull Scientific Event Alert Network (SEAN), v 1-14.

Sun C-H, Stern R J, 2001. Genesis of Mariana shoshonites: contribution of the subduction component. J Geophys Res, 106: 589-608.

Volcano Types

Submarine

Tectonic Setting

Subduction zone
Crustal thickness unknown

Rock Types

Major
Trachyandesite / Basaltic trachy-andesite

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
0
0
0
26

Affiliated Databases

Large Eruptions of Minami-Hiyoshi Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
Smithsonian Collections Search the Smithsonian's NMNH Department of Mineral Sciences collections database. Go to the "Search Rocks and Ores" tab and use the Volcano Name drop-down to find samples.