Akagisan
Stratovolcano in Japan
Key Facts
Elevation
1,828 m (5,997 ft)
Type
Stratovolcano
Location
36.560°, 139.193°
Region
Northeast Japan Volcanic Arc
Rock Type
Andesite / Basaltic Andesite
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
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.
Volcanic Hazards & Risk Assessment
Primary Hazards
- Pyroclastic flows
- Lava flows
- Volcanic bombs and ballistics
- Lahars and mudflows
Risk Level
Geological Composition & Structure
Rock Types
Tectonic Setting
Age & Formation
Eruption Statistics & Analysis
| Metric | Value | Global Ranking | Significance |
|---|---|---|---|
| Total Recorded Eruptions | Unknown | Low | Moderately active volcano |
| Maximum VEI | VEI Unknown | Minor | Local impact potential |
| Recent Activity | Unknown | Historical | Historically active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Northwestern Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 283130
- •Evidence: Evidence Uncertain
- •Epoch: Holocene
About the Photo
Akagisan at the northern end of the Kanto Plain has a 3 x 4 km summit caldera that contains lava domes. Lake Ono, seen here from the SW with the summit of the volcano to the upper right, occupies the NE end of the caldera. Most of the activity occurred during the Pleistocene when a series of large Plinian eruptions accompanied growth of a second cone.
Photo by Ichio Moriya (Kanazawa University).
Authority Sources
Related Volcanoes
Basic Information
This page shows basic data from the Smithsonian Global Volcanism Program. For more detailed information, visit the official Smithsonian page.