Akan Volcanic Complex | |
---|---|
![]() Mount Meakan, Akan-Fuji and Mount Oakan on a satellite image of Eastern Hokkaido | |
Highest point | |
Peak | Mount Meakan |
Elevation | 1,499 m (4,918 ft) |
Coordinates | 43°23′11″N 144°00′32″E / 43.38639°N 144.00889°E |
Naming | |
Native name | |
Geography | |
Country | Japan |
State | Hokkaidō |
Subprefectures | Kushiro and Tokachi |
Districts | Ashoro District and Shiranuka District |
Municipalities | Ashoro, Kushiro and Shiranuka |
Geology | |
Orogeny | island arc |
Type of rock | Volcanic |
Last eruption | November 2008 |
![](https://upload.wikimedia.org/wikipedia/commons/thumb/0/06/Akan_Caldera_Relief_Map%2C_SRTM.jpg/220px-Akan_Caldera_Relief_Map%2C_SRTM.jpg)
Me-Akan (bottom left)
O-Akan (center right)
![](https://upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Meakandake_funka.jpg/220px-Meakandake_funka.jpg)
Akan Volcanic Complex is a volcanic group of volcanoes that grew out of the Akan caldera.[1] It is located within Akan National Park, about 50 km Northwest of Kushiro in eastern Hokkaidō, Japan.
Description
[edit]A number of peaks are arranged around the rim of Lake Akan (a.k.a. Akan-ko[2]), which fills a 24×13 km caldera,[3] the tallest being Me-Akan (Meakan), O-Akan (Oakan) and Akan-Fuji.[1]
Oakan is prominently located at the northeast side of the caldera, while Meakan occupies the opposite, southwest side, in a cluster of nine stratovolcanoes that include Akan-Fuji, one of many symmetrical Japanese volcanoes named after the renowned Mount Fuji, and Fuppushi volcano[4] (a.k.a. Fuppushi-dake, not to be confused with Mount Fuppushi, which is located in Southwestern Hokkaido).
Volcanology
[edit]The Akan caldera was formed 31,500 years ago. Its elongated shape is due to its incremental formation during major explosive eruptions, from the early to the mid-Pleistocene periods.
The Nakamachineshiri crater of Meakan volcano was formed during a major eruption about 13,500 years ago.
The Me-Akan group of nine overlapping cones on the eastern side of Lake Akan has had mild eruptions since the beginning of the 19th century.[5] The last eruption of this historical volcano was in 2008.[3]
Oakan, Meakan, Furebetsu and Fuppushi are the major post-caldera volcanoes of the Akan volcanic complex.[1]
Me-Akan is one of the most active volcanoes of Hokkaido. Its summit contains the active craters of Ponmachineshiri and Naka-Machineshiri, sites of frequent phreatic eruptions in historical time. Akan-Fuji and O-Akan have not erupted in historical time.[4]
Akan is rated with a volcanic explosivity index of 4 on the Smithsonian VEI scale, the scale's fourth-highest score, based on the volcano's largest known eruption, around 7050 BC.[6]
Following are prominent features of Akan:[7]
Cones
[edit]- Me-Akan-Dake (Mount Meakan) (1499 m) Stratovolcano
- Akan Fuji (Akan-Fuji, Akan-Huji) (1476 m) Stratovolcano
- Kita-Yama (1400 m) Cone
- O-Akan-Dake (Mount Oakan) (1371 m) Stratovolcano
- Kenga-Mine Cone 1336 m
- Nishi-Yama (Nisi-Yama) (1300 m) Cone
- Fuppushi (Huppusi) (1226 m) Stratovolcano
- Miname-Dake (1217 m) Stratovolcano
- Higashi-Dake (Higasi-Dake) (1140 m) Cone
- Furebetsu (Hurebetu) (1098 m) Stratovolcano
- Kobu-Yama Cone
- Futatsu-Dake Pyroclastic cone
Craters
[edit]- Nakamachineshiri (Nakamatineshiri) Crater
- Ponmachineshiri (Ponmatinesiri) Crater
Thermal features
[edit]- Akan-Kohan Thermal Feature
Other peaks
[edit]- Mount Ken[citation needed]
- Mount Ahoro[citation needed]
References
[edit]- ^ a b c "AKAN Caldera". Quaternary Volcanoes of Japan, Geological Survey of Japan, AIST, 2006. Archived from the original on 2012-12-19. Retrieved 2011-03-09.
- ^ "Akan-ko: Japan". Geographical Names. Retrieved 2011-03-09.
- ^ a b "Akan". Global Volcanism Program. Smithsonian Institution. Retrieved 2021-06-25.
- ^ a b "Akan Volcanic Complex, Japan". Volcano Photos. Retrieved 2011-03-09.
- ^ "MEAKAN-DAKE". Quaternary Volcanoes of Japan, Geological Survey of Japan, AIST, 2006. Archived from the original on 2012-12-19. Retrieved 2011-03-09.
- ^ "Large Volcano Explocivity Index". Countries of the World. Retrieved 2011-03-09.
- ^ "Akan: Synonyms & Subfeatures". Global Volcanism Program. Smithsonian Institution. Retrieved 2021-06-25.
External links
[edit]- Akan Caldera - Geological Survey of Japan
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