Rishirizan
Stratovolcano in Japan
Key Facts
Elevation
1,721 m (5,646 ft)
Type
Stratovolcano
Location
45.179°, 141.242°
Region
Kuril Volcanic Arc
Rock Type
Andesite / Basaltic Andesite
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
Rishirizan is a highly dissected andesitic stratovolcano that forms a 20-km-wide island west of the northern tip of Hokkaido. Extensive erosion has produced an extremely rugged topography, with a dramatic sharp-topped, summit flanked by steep-sided radial ridges. A stratovolcano and flank lava domes were constructed beginning less than 200,000 years ago.
After about 37,000 years ago only flank vents were active. Late-stage eruptions took place from scoria cones and maars along a 15-km-long NW-SE trend that extends to the SE coast. Flank eruptions were dominantly basaltic, but also included andesitic and rhyolitic activity.
Extensive lava flows during the late Pleistocene form much of the northern and western coasts and extend offshore. The latest eruptions took place a few thousand years ago.
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 | 7856 years ago | Historical | Historically active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Northwestern Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 285041
- •Evidence: Eruption Dated
- •Epoch: Holocene
About the Photo
Rishiri is a highly eroded edifice forming an island off the NW tip of Hokkaido. The main edifice contains scoria cones on the flanks, with a maar containing this lake on the lower S flank. It was constructed during the Pleistocene and scoria cones and the maars on the lower flanks erupted 30,000-8,000 years ago.
Photo by Yoshihiro Ishizuka, 1993 (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.