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  • Japan
  • Honshu
  • Stratovolcano(es)
  • 1971 CE
  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 39.761°N
  • 140.799°E

  • 1637 m
    5369 ft

  • 283230
  • Latitude
  • Longitude

  • Summit

  • Volcano

There are no activity reports for Akita-Komagatake.

 Available Weekly Reports

There are no Weekly Reports available for Akita-Komagatake.

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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1970 Sep 18 1971 Jan 26 Confirmed 2 Historical Observations Me-dake
1932 Jul 21 1932 Jul 24 Confirmed 2 Historical Observations Ishibora (south flank of Me-dake)
1902 Unknown Confirmed 1 Historical Observations Yoko-dake
1890 Dec 1891 Jan Confirmed 2 Historical Observations
1100 (?) Unknown Confirmed 2 Tephrochronology
0807 (?) Unknown Confirmed 3 Historical Observations AK-1 tephra
0400 ± 500 years Unknown Confirmed   Tephrochronology Me-dake
0050 BCE ± 200 years Unknown Confirmed 2 Radiocarbon (corrected) AK-2 tephra
0200 BCE ± 200 years Unknown Confirmed   Radiocarbon (corrected) Minami-dake, Ko-dake
0350 BCE ± 200 years Unknown Confirmed 3 Radiocarbon (corrected) AK-3 tephra
1450 BCE ± 50 years Unknown Confirmed   Radiocarbon (corrected) AK-5, AK-4 tephra layers
5950 BCE ± 200 years Unknown Confirmed 3 Radiocarbon (corrected) AK-6 tephra
6150 BCE ± 300 years Unknown Confirmed   Tephrochronology
6350 BCE ± 200 years Unknown Confirmed 3 Radiocarbon (corrected) AK-7 tephra
7100 BCE ± 1000 years Unknown Confirmed   Tephrochronology
7850 BCE ± 200 years Unknown Confirmed 4 Radiocarbon (corrected) AK-8, Horikiri tephra
8300 BCE ± 300 years Unknown Confirmed 4 Tephrochronology AK-9, Arasawa tephra
8800 BCE ± 300 years Unknown Confirmed 3 Tephrochronology AK-11, AK-10 tephra layers

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.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

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.

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, http://www.aist.go.jp/RIODB/strata/VOL_JP/.

Wachi T, Doi N, Koshiya S, 1997. Tephra stratigraphy and eruptive activities of the Akita-Komagatake volcano. Bull Volc Soc Japan (Kazan), 42: 17-34 (in Japanese with English abs).

Yagi K, Takeshita H, Oba Y, 1972. Petrological study on the 1970 eruption of Akita-Komagatake volcano, Japan. Hokkaido Univ Fac Sci Jour, 15: 109-138.

Two calderas partially filled by basaltic cones cut the summit of Akita-Komagatake volcano. The larger southern caldera is 1.5 x 3 km wide and has a shallow sloping floor that is drained through a narrow gap cutting the SW caldera rim. On its northern side the southern caldera borders a smaller more circular 1.2-km-wide caldera, whose rim is breached widely to the NE. The two calderas were formed following explosive eruptions at the end of the Pleistocene, between about 13,500 and 11,600 years ago. Two cones, Medake and Kodake, occupy the NE corner of the southern caldera, whose long axis trends NE-SW. The highest point of the volcano is a cone within the northern caldera, 1637-m-high Komagatake (also known as Onamedake), which has produced lava flows to the north and east and has a 100-m-wide summit crater. Small-scale historical eruptions have occurred from cones and fissure vents inside the southern caldera.