Akan
Caldera in Japan
Key Facts
Elevation
1,499 m (4,918 ft)
Type
Caldera
Location
43.384°, 144.013°
Region
Kuril Volcanic Arc
Total Eruptions
36
Max VEI
VEI 4
Rock Type
Andesite / Basaltic Andesite
Tectonic Setting
Subduction zone
Location
Loading map...
Eruption Timeline
Minor phreatic eruption at Meakandake
Small phreatic eruption
Phreatic eruptions from Ponmachineshiri crater
Minor eruption at Meakandake
Small phreatic activity
Phreatomagmatic eruption
Eruption at Meakandake with ashfall
Minor activity
Phreatic eruption
Small eruption
Minor phreatic activity
Small eruption at crater
Phreatic eruption
Minor activity
Small eruption
Moderate eruption with ash emissions
Minor phreatic eruption
Small eruption
Historical eruption
Early 19th century activity
Overview
Akan is a 13 x 24 km caldera located immediately SW of Kussharo caldera in eastern Hokkaido. The elongated, irregular outline of the caldera rim reflects its incremental formation during major explosive eruptions from the early to mid-Pleistocene. There are four post-caldera stratovolcanoes, three at the SW end of the caldera and the other on the NE side.
Conical Oakandake was frequently active during the Holocene. The 1-km-wide Nakamachineshiri crater of Meakandake was formed during a major pumice-and-scoria eruption about 13,500 years ago. The Meakandake group, composed of nine overlapping cones E of Lake Akan, has produced mild phreatic eruptions since the beginning of the 19th century.
The main cone of Meakandake proper has a triple crater at its summit. Although recorded eruptions at Meakandake have consisted of minor phreatic explosions, four major magmatic eruptions with pyroclastic flows have also occurred during the Holocene.
Volcanic Hazards & Risk Assessment
Primary Hazards
- Pyroclastic flows and surges
- Large explosive eruptions (VEI 4+)
- Ash fall and tephra deposits
- Lahars and debris flows
Risk Level
Geological Composition & Structure
Rock Types
Tectonic Setting
Age & Formation
Eruption Statistics & Analysis
| Metric | Value | Global Ranking | Significance |
|---|---|---|---|
| Total Recorded Eruptions | 36 | High | Highly active volcano |
| Maximum VEI | VEI 4 | Major | Regional impact potential |
| Recent Activity | 1 years ago | Very Recent | Currently active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Northwestern Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 285070
- •Evidence: Eruption Observed
- •Epoch: Holocene
About the Photo
Oakandake, the largest post-caldera cone at Akan volcano, is seen here from the W across the Akan Caldera lake. It was constructed at the NE end of the 13 x 14 km caldera, opposite a cluster of stratovolcanoes at the SW end. Meakan in the SW group has been frequently active.
Photo by Wataru Hirose, 1996 (Hokkaido 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.