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  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 36.56°N
  • 139.193°E

  • 1828 m
    5996 ft

  • 283130
  • Latitude
  • Longitude

  • Summit

  • Volcano

The Global Volcanism Program has no activity reports for Akagisan.

The Global Volcanism Program has no Weekly Reports available for Akagisan.

The Global Volcanism Program has no Bulletin Reports available for Akagisan.

Volcano Types

Lava dome(s)

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Rock Types

Andesite / Basaltic Andesite


Within 5 km
Within 10 km
Within 30 km
Within 100 km

Geological Summary

The broad, low dominantly andesitic Akagisan volcano rises above the northern end of the Kanto Plain. It contains an elliptical, 3 x 4 km summit caldera with post-caldera lava domes arranged along a NW-SE line. Lake Ono is located at the NE end of the caldera. An older stratovolcano was partially destroyed by edifice collapse, producing a debris-avalanche deposit along the south flank. A series of large plinian eruptions accompanied growth of a second stratovolcano during the Pleistocene. Construction of the central cone in the late-Pleistocene summit caldera began following the last of the plinian eruptions about 31,000 years ago. During historical time unusual activity was recorded on several occasions during the 9th century, but reported eruptions in 1251 and 1938 are considered uncertain.

Eruptive History

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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1938 Jul 16 (in or before) ] [ Unknown ] Uncertain    
[ 1251 May 18 ] [ Unknown ] Uncertain    

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.




Feature Name Feature Type Elevation Latitude Longitude
Kono Crater 1580 m


Feature Name Feature Type Elevation Latitude Longitude
Dome 1580 m
Dome 1674 m
Miharashi-yama Dome 1440 m
Suzuga-take Dome 1565 m

Photo Gallery

The broad low volcano of Akagi at the northern end of the Kanto Plain contains an elliptical, 3 x 4 km summit caldera with post-caldera lava domes arranged along a NW-SE line. Lake Ono, seen here from the SW with the summit of the volcano at the upper right, occupies the NE end of the caldera. Most of the activity of Akagi occurred during the Pleistocene, when a series of large plinian eruptions accompanied growth of a second stratovolcano. Only one somewhat uncertain eruption was recorded in historical time, in 1251 AD.

Photo by Ichio Moriya (Kanazawa University).
The lake-filled summit caldera of Akagi volcano is a popular winter skiing and ice-skating destination for residents of Tokyo and surrounding areas. Kurohinoki-yama, across Lake Ono to the NE, is the highest point on the caldera rim of Akagi, 350 m above the lake.

Photo by Lee Siebert, 1965 (Smithsonian Institution).


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.

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

Kobayshi K, Nakamura E, 2001. Geochemical evolution of Akagi volcano, NE Japan: implications for interaction between island-arc magma and lower crust, and generation of isotopically various magmas. J Petr, 42: 2303-2331.

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

Moriya I, 1970. History of Akagi volcano. Bull Volc Soc Japan (Kazan), 15: 120-131 (in Japanese with English abs).

Murayama I, 1989. Volcanoes of Japan (II). Tokyo: Daimedo, 285 p (in Japanese).

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/.

Suzuki T, 1996. Discharge rates of fallout tephra and frequency of plinian eruptions during the last 400,000 years in the southern Northeast Japan arc. Quat Internatl, 34-36: 79-87.

Suzuki T, 1990. Tephrochronological study on the 200,000 years eruptive history of Akagi volcano in north Kanto, central Japan. Chigaku Zasshi (Jour Geog), 99: 60-75 (in Japanese with English abs).

Affiliated Databases

Large Eruptions of Akagisan 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.