About Toshima
Toshima is a stratovolcano rising to 508 meters (1,667 feet) in Japan's Northwestern Pacific Volcanic Regions. The volcano is currently active, with its most recent eruption in 4550 BCE. The volcano has produced 1 recorded eruption.
Geography & Climate
Toshima is located in Japan, within the Izu Volcanic Arc of the broader Northwestern Pacific Volcanic Regions. Situated at 34.52° N, 139.28° E in the Northern Hemisphere, the volcano lies within a subtropical climate zone. With a summit elevation of 508 meters above sea level, Toshima is a moderately sized peak that remains accessible to hikers and researchers for much of the year. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.
Geological Context
Toshima sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Japan near Toshima, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is basalt / picro-basalt, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.
Eruption History Summary
Toshima has 1 recorded eruption in the geological database, spanning from 4550 BCE to 4550 BCE.
GVP Reference Summary
The small 2 x 2.4 km island of Toshima is located in the northern Izu Islands south of Izu-Oshima Island about 20 km W of the main volcanic front. Steep cliffs up to 300 m high ring the basaltic to basaltic andesite island on three sides. The summit is asymmetrically located opposite the more gentle slopes of the northern side of the island, where the village of Toshima is located. The latest known eruption of this stratovolcano occurred sometime between about 9,000 and 4,000 years ago, producing a lava flow from Kajiana crater.
— Smithsonian Institution, Global Volcanism Program
1 Recorded Eruption
| Year | VEI | Type | Area |
|---|---|---|---|
| 4550 BCE | 0 | Confirmed Eruption | Kajiana crater |
Real-Time Data
USGS Alert Level
Thermal Anomalies
Frequently Asked Questions About Toshima
Is Toshima an active volcano?+
Toshima is not currently classified as active. Its activity evidence is listed as "Eruption Dated." The last known eruption was in 4550 BCE. However, no volcano is ever considered permanently extinct.
When did Toshima last erupt?+
The most recent recorded eruption of Toshima occurred in 4550 BCE with a Volcanic Explosivity Index (VEI) of 0. The eruption was classified as a "Confirmed Eruption." Toshima has 1 recorded eruption in total.
How high is Toshima?+
Toshima has a summit elevation of 508 meters (1,667 feet) above sea level. At 508 meters, it is a relatively low-elevation volcano.
What type of volcano is Toshima?+
Toshima is classified as a Stratovolcano. Stratovolcanoes (also called composite volcanoes) are steep, conical volcanoes built up by many layers of hardened lava, tephra, and volcanic ash. They are among the most common and dangerous types, known for explosive eruptions.
Where is Toshima located?+
Toshima is located in Japan, in the Northwestern Pacific Volcanic Regions. More specifically, it lies within the Izu Volcanic Arc. Its exact coordinates are 34.520° latitude, 139.279° longitude.
Is it safe to visit Toshima?+
Toshima can generally be visited, but as with any volcano, visitors should check local conditions and any advisory notices before traveling. Japan may have specific regulations for accessing volcanic areas. Guided tours are often the safest and most informative way to experience a volcano.
