What kind of volcano is Asama?

Asama is classified as a Complex volcano in Japan. Its tectonic setting is Subduction zone / Continental crust (> 25 km).

How is seismicity near Asama monitored here?

Earthquakes within 50 km of the crater are aggregated from 18 seismic networks and checked against a swarm rule that compares the current rate with this volcano's own 30-day background. Ash advisories come from the VAAC centres that are connected.

Steep slopes and summit craters of Mount Asama in central Honshu

Photo:Richard Fiskevia Smithsonian GVP

Volcano Dossier•GVP #283110

36.41°N, 138.52°E

Erupted since 2000

Japan→

Volcano Asama

One of Honshu's most active volcanoes, about 140 km northwest of Tokyo. The great eruption of 1783 sent a debris avalanche and lahars that killed some 1,500 people, and its ash worsened the Tenmei famine. Frequent small explosions keep it among Japan's most closely monitored volcanoes.

Last eruption

2019

Erupted since 2000

Summit

2.6 km

Complex volcano · Andesite / Basaltic Andesite

Activity

Normal Baseline

0 events (1.0x rate)

Interactive Volcano & Seismicity Map

Seismicity within 50 km radius, active VAAC ash plumes, and tectonic plate boundaries.

Recent seismicity within 50 km

0 events in the last 12 h within 25 km of the crater.

No catalogued earthquakes within 50 km in the last 90 days.

Geological & Tectonic Profile

Complex volcano

Asama is an active Complex volcano formed in an active Subduction zone / Continental crust (> 25 km). Dominant lithology: Andesite / Basaltic Andesite.

Edifice TypeComplex volcano

Major rockAndesite / Basaltic Andesite

TectonicsSubduction zone

Volcanic ArcNortheast Japan Volcanic Arc

Volcano Dossier

VN #283110

Official catalogue parameters, coordinates, elevation and geotectonic classification.

CountryJapan

Crater Coordinates36.406°, 138.523°

Summit2.6 km

SubregionNortheast Japan Volcanic Arc

Catalog SourceSmithsonian GVP (#283110)

Authoritative Monitoring Infrastructure

All 18 Networks & VAAC →

Seismic ObservatoryJMA

Japan Meteorological Agency (Volcano Observation)

Official Portal

ICAO Aviation Ash Center

Tokyo VAAC (JMA)

Tokyo, Japan

VAAC Advisory Desk

Swarm telemetry correlated across 18 networks against a 30-day baseline.Read Science & Physics →

Regional Seismic Profile

Tokyo & Kanto Plain

Explore live seismic monitoring, historical danger benchmarks, fault slip models and recurrence intervals for Tokyo & Kanto Plain.

Open Regional Hub

Frequently Asked Questions (FAQ)

Verified scientific, operational, and emergency protocols

The most recent eruption of Asama recorded by the Smithsonian Global Volcanism Program was in 2019.

Catalogue: Smithsonian Institution, Global Volcanism Program.Smithsonian GVP profile