Izu-Torishima

Photo of this volcano
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 30.484°N
  • 140.303°E

  • 394 m
    1292 ft

  • 284090
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 3 July-9 July 2013 Citation IconCite this Report


According to the Tokyo VAAC a pilot observed an ash plume from Tori-shima drifting at an altitude of 2.1 km (7,000 ft) a.s.l. on 6 July.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


Most Recent Bulletin Report: October 2002 (BGVN 27:10) Citation IconCite this Report


Mid-August 2002 plumes, larger crater, and discolored water

Following ship-based reports of activity at Tori-shima on 11 August 2002, scientists from the Japanese Meterological Agency overflew the area the next day when they observed and photographed ash plumes being erupted from the crater (BGVN 27:07). According to the Japan Coast Guard (via JMA), the activity continued as of 1200 on 14 August; the plume reached ~1.2-1.5 km above sea level on 13 August (figure 3), and ~900 m on 14 August. Emissions were observed from three active areas along the western inner-wall of the summit crater. The crater appeared to have widened. By 21 August, the Japan Coast Guard reported that Izu-Tori-shima no longer "smoked" and only weak steaming was seen in the southern portion of the crater. Faintly discolored sea surface was observed around the island.

Figure (see Caption) Figure 3. Izu-Tori-Shima plume on 13 August 2002. Courtesy Air Force Weather Agency.

Information Contacts: Tomonori Kannno and Hitoshi Yamasato, Japanese Meteorological Agency (JMA), Volcanological Division, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan (URL: http://www.kishou.go.jp/english/, Email: tkanno@met.kishou.go.jp, yamasato@met.kishou.go.jp); Volcano Research Center (VRC), Earthquake Research Institute (ERI), University of Tokyo (URL: http://hakone.eri.u-tokyo.ac.jp/vrc/erup/torisima.html); U.S. Air Force Weather Agency, Offutt AFB, NE 68113-4039, USA.

Weekly Reports - Index


2013: July
2002: August


3 July-9 July 2013 Citation IconCite this Report


According to the Tokyo VAAC a pilot observed an ash plume from Tori-shima drifting at an altitude of 2.1 km (7,000 ft) a.s.l. on 6 July.

Source: Tokyo Volcanic Ash Advisory Center (VAAC)


21 August-27 August 2002 Citation IconCite this Report


An eruption began at Tori-shima on 11 August and an aerial inspection by the Japan Coast Guard on 21 August revealed that "smoke" was no longer rising from the volcano as it had been on the 14th. Weak steaming was visible in the southern part of the crater. In addition, the sea surface around the island was faintly discolored.

Source: Japan Meteorological Agency (JMA) via the Volcano Research Center


14 August-20 August 2002 Citation IconCite this Report


The eruption that began at Tori-shima on 11 August continued until at least noon on the 14th. Eruption clouds reached ~1.2 km a.s.l. on the 13th and ~1 km a.s.l. on the 14th. During observations on the 14th, scientists found smoke was being emitted from three areas on the western inner wall of the summit crater. They also found that the crater seemed to have widened during the eruption and the sea surface was no longer discolored.

Source: Japan Meteorological Agency (JMA) via the Volcano Research Center


7 August-13 August 2002 Citation IconCite this Report


On 11 August around 1530 a ship sailing near Tori-shima reported to the Japan Coast Guard that they observed white smoke rising from the summit of the volcano. JMA reported that an aerial inspection the following day during 1145-1245 revealed an ash-laden plume rising from the SW crater wall of the summit crater (Iwoyama) and white plumes emanating from the S to SE portion of the crater wall. Vigorous ash plumes rose 200-300 m above the crater every few minutes, drifted W, and ultimately reached a height of 1 km a.s.l. The summit area and the middle slope NNW of the summit were covered with ash-fall deposits. Discolored sea water extended 20 km W of the island. Tori-shima is not inhabited by humans, but an endangered albatross species lives there.

Sources: Japan Meteorological Agency (JMA) via the Volcano Research Center; Associated Press; Reuters; NOAA Marine Forecasts


Bulletin Reports - Index


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) Possible submarine eruption in October 1975

07/2002 (BGVN 27:07) Ash plumes during August 2002 indicate first activity since 1975

10/2002 (BGVN 27:10) Mid-August 2002 plumes, larger crater, and discolored water




Information is preliminary and subject to change. All times are local (unless otherwise noted)


January 1977 (NSEB 02:01) Citation IconCite this Report


Possible submarine eruption in October 1975

[A table of possible submarine eruptions based on aerial observations of water discoloration by the Japanese Maritime Safety Agency included an entry for 30.38°N, 140.32°E, in October 1975. This location is ~11 km S of Tori-shima.]

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


July 2002 (BGVN 27:07) Citation IconCite this Report


Ash plumes during August 2002 indicate first activity since 1975

Around 1530 on 11 August 2002, a ship sailing near Tori-shima reported white smoke rising from the summit of the island. The Japanese Coast Guard inspected the island from the air during 1738-1818 and confirmed that the plume was rising 200-300 m from near the summit crater (Iwo-yama).

During an overflight on 12 August from 1145 to 1245 by the Japanese Meteorological Agency (JMA), an ash-laden plume was rising from the SW wall of the Iwo-yama summit crater. White plumes were also observed rising from the S to SE crater wall (figures 1 and 2). A vigorous ash plume rose 200-300 m above the crater every few minutes and drifted W to ~1 km above sea level. The summit area and the middle slope NNW of the summit were covered with ashfall deposits. The sea surface was discolored in an area up to 20 km W of the island. Izu-Tori-shima island is currently uninhabited.

Figure (see Caption) Figure 1. Photo showing the Iwo-yama crater of Tori-shima volcano, taken around 1200 on 12 August 2002. Courtesy JMA.
Figure (see Caption) Figure 2. Southern view of Tori-shima volcano showing ash plume from the summit crater, taken around 1200 on 12 August 2002. Courtesy JMA.

Information Contacts: Tomonori Kannno and Hitoshi Yamasato, Japanese Meteorological Agency (JMA), Volcanological Division, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan (URL: http://www.kishou.go.jp/ english/, Email: tkanno@met.kishou.go.jp, yamasato@met.kishou.go.jp).


October 2002 (BGVN 27:10) Citation IconCite this Report


Mid-August 2002 plumes, larger crater, and discolored water

Following ship-based reports of activity at Tori-shima on 11 August 2002, scientists from the Japanese Meterological Agency overflew the area the next day when they observed and photographed ash plumes being erupted from the crater (BGVN 27:07). According to the Japan Coast Guard (via JMA), the activity continued as of 1200 on 14 August; the plume reached ~1.2-1.5 km above sea level on 13 August (figure 3), and ~900 m on 14 August. Emissions were observed from three active areas along the western inner-wall of the summit crater. The crater appeared to have widened. By 21 August, the Japan Coast Guard reported that Izu-Tori-shima no longer "smoked" and only weak steaming was seen in the southern portion of the crater. Faintly discolored sea surface was observed around the island.

Figure (see Caption) Figure 3. Izu-Tori-Shima plume on 13 August 2002. Courtesy Air Force Weather Agency.

Information Contacts: Tomonori Kannno and Hitoshi Yamasato, Japanese Meteorological Agency (JMA), Volcanological Division, 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100, Japan (URL: http://www.kishou.go.jp/english/, Email: tkanno@met.kishou.go.jp, yamasato@met.kishou.go.jp); Volcano Research Center (VRC), Earthquake Research Institute (ERI), University of Tokyo (URL: http://hakone.eri.u-tokyo.ac.jp/vrc/erup/torisima.html); U.S. Air Force Weather Agency, Offutt AFB, NE 68113-4039, USA.

Eruptive History


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


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 2013 Jul 6 ] [ 2013 Jul 6 ] Uncertain 2  
2002 Aug 12 2002 Aug 20 Confirmed 2 Historical Observations Iwo-yama
1975 Oct 2 Unknown Confirmed 2 Historical Observations 9 km S of Torishima
1965 Nov 13 1965 Dec 5 ± 4 days Confirmed 0 Hydrophonic
1939 Aug 17 1939 Dec 26 ± 5 days Confirmed 3 Historical Observations North side of 1902 crater (Iwo-yama)
1902 Aug 7 1902 Aug 24 Confirmed 3 Historical Observations Komochi-yama, N & SW offshore flanks
1871 Apr Unknown Confirmed 0 Historical Observations

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.

Photo Gallery


An August 12, 2002 photo shows an ash plume rising from the summit crater of Tori-shima volcano. The unvegetated cone of Iwo-yama, seen here from the south, was constructed during an eruption in 1939 within a 1.5-km-wide caldera that truncates the eroded flanks of the volcano. The circular, 2.7-km-wide island of Tori-shima is located in the southern Izu Islands. The volcano is also referred to as Izu-Tori-shima to distinguish it from the several other Japanese island volcanoes called Tori-shima ("Bird Island").

Photo courtesy of Japan Meteorological Agency, 2002.
See title for photo information.
The dark-colored lava flow along the coast in the foreground was emplaced during an eruption that began on 17 August 1939. A new cinder cone (Iwo-yama) was constructed in that year at the north end of the 1902 crater. Two lava flows reached the sea, the first at Hyogo-wan (the bay at the far right) and the second at Chitose Bay. Two people were killed during the eruption, which ended at the end of December.

Copyrighted photo by Akira Takada (Japanese Quaternary Volcanoes database, RIODB, http://riodb02.ibase.aist.go.jp/strata/VOL_JP/EN/index.htm and Geol Surv Japan, AIST, http://www.gsj.jp/).
See title for photo information.

Smithsonian Sample Collections Database


There are no samples for Izu-Torishima in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

Affiliated Sites