Available Weekly Reports
21 August-27 August 2002
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.
Sources: Japan Meteorological Agency (JMA) via the Volcano Research Center
21 August 2002Back to Top
14 August 2002Back to Top
7 August 2002Back to Top
Summary of eruption dates and Volcanic Explosivity Indices (VEI).
|Start Date||Stop Date||Eruption Certainty||VEI||Evidence||Activity Area or Unit|
|2002 Aug 12||2002 Aug 20||Confirmed||2||Historical||Iwo-yama|
|1975 Oct 2||Unknown||Confirmed||2||Historical||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||North side of 1902 crater (Iwo-yama)|
|1902 Aug 7||1902 Aug 24||Confirmed||3||Historical||Komochi-yama, N & SW offshore flanks|
The circular, 2.7-km-wide island of Tori-shima in the southern Izu Islands is capped by an unvegetated summit cone formed during an eruption in 1939. Fresh lava flows from this eruption form part of the northern coastline of the basaltic-to-dacitic edifice. 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"). The main cone is truncated by a 1.5-km-wide caldera that contains two central cones, of which 394-m-high Iwo-yama is the highest. Historical eruptions have also occurred from flank vents near the north coast and offshore submarine vents. A 6-8 km wide submarine caldera lies immediately to the north of Tori-shima.