Photo of this volcano
Google Earth icon
Google Earth Placemark
  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 27.881°N
  • 128.223°E

  • 212 m
    695 ft

  • 282020
  • Latitude
  • Longitude

  • Summit

  • Volcano

There are no activity reports for Io-Torishima.

 Available Weekly Reports

There are no Weekly Reports available for Io-Torishima.

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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1968 Jul 18 1968 Jul 18 Confirmed 1 Historical Observations
1967 Nov 25 ± 5 days Unknown Confirmed 1 Historical Observations
1959 Jun 8 1959 Jul Confirmed 2 Historical Observations Iwo-dake
1903 Mar 15 ± 5 days 1903 Aug 26 ± 5 days Confirmed 2 Historical Observations
1868 Feb 1868 Apr Confirmed 1 Historical Observations
1855 Mar 1855 May Confirmed 2 Historical Observations
1829 Dec 1 1829 Dec 16 Confirmed 1 Historical Observations
1796 Oct 1796 Nov Confirmed 2 Historical Observations Iwo-dake
1664 Unknown Confirmed   Historical Observations

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. 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. Additional discussion of data sources can be found under Volcano Data Criteria.

Hayakawa Y, 1996. . (pers. comm.).

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, 1975. National Catalogue of the Active Volcanoes in Japan. Tokyo: Japan Meteorological Agency, 119 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,

Kuno H, 1962. Japan, Taiwan and Marianas. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 11: 1-332.

Nakano S, Yamamoto T, Iwaya T, Itoh J, Takada A, 2001-. Quaternary Volcanoes of Japan. Geol Surv Japan, AIST,

The 1 x 2.7 km island of Io-Torishima, located north of the largest island of the Ryukyus, Okinawa, is composed of two andesitic volcanoes. Torishima (Bird Island) is a common name for offshore islands in Japan. Kusuku lava dome occupies the center of the inner of two sommas on the SE-most volcano. The summit crater of the NW-most volcano, Iodake, contains a small lake, solfataras, and sulfur deposits that were mined in the past. Historical eruptions dating back to 1664 have consisted of mild-to-moderate explosive activity.