Kujusan
Stratovolcano(es) in Japan
Key Facts
Elevation
1,791 m (5,876 ft)
Type
Stratovolcano(es)
Location
33.086°, 131.249°
Region
Nankai Volcanic Arc
Rock Type
Andesite / Basaltic Andesite
Tectonic Setting
Subduction zone
Location
Loading map...
Overview
Kujusan is a complex of stratovolcanoes and lava domes lying NE of Aso caldera in north-central Kyushu. The group consists of 16 andesitic lava domes, five andesitic stratovolcanoes, and one basaltic cone. Activity dates back about 150,000 years.
Six major andesitic-to-dacitic tephra deposits, many associated with the growth of lava domes, have been recorded during the Holocene. Eruptive activity has migrated systematically eastward during the past 5000 years. The latest magmatic activity occurred about 1600 years ago, when Kurodake lava dome at the E end of the complex was formed.
The first reports of historical eruptions were in the 17th and 18th centuries, when phreatic or hydrothermal activity occurred. There are also many hot springs and hydrothermal fields. A fumarole on Hosho lava dome was the site of a sulfur mine for at least 500 years.
Two geothermal power plants are in operation at Kuju.
Volcanic Hazards & Risk Assessment
Primary Hazards
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 | 30 years ago | Recent | Recently active |
Monitoring & Alert Status
Monitoring Networks
Current Status
Nearby Volcanoes in Western Pacific Volcanic Regions
Quick Info
- •Smithsonian ID: 282120
- •Evidence: Eruption Observed
- •Epoch: Holocene
About the Photo
The Kuju volcano group in northern Kyushu consists of more than ten cones and lava domes NE of Aso caldera. This view from the E shows Mimatayama (right) and Nakadake (left) lava domes, which formed about 10,000-12,000 years ago. Gas-and-steam plumes rising from fumaroles are seen here in 1994 on the flank of Hosshozan (center), the site of small phreatic explosions in November 1995. Many hot springs and hydrothermal fields are located at the Kuju complex.
Photo by Yasuo Miyabuchi, 1994 (Forestry and Forest Products Research Institute, Kyushu).
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.