About Yoteizan
Yoteizan is a stratovolcano rising to 1,888 meters (6,195 feet) in Japan's Northwestern Pacific Volcanic Regions. Its last known eruption dates to 1050 BCE, in prehistoric times. The volcano has produced 2 recorded eruptions.
Geography & Climate
Yoteizan is located in Japan, within the Northeast Japan Volcanic Arc of the broader Northwestern Pacific Volcanic Regions. Situated at 42.83° N, 140.81° E in the Northern Hemisphere, the volcano lies within a temperate climate zone. With a summit elevation of 1,888 meters above sea level, Yoteizan 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
Yoteizan 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 Yoteizan, 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 andesite / basaltic andesite, 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
Yoteizan has 2 recorded eruptions in the geological database, spanning from 3550 BCE to 1050 BCE. These eruptions span roughly 2,500 years of volcanic history.
GVP Reference Summary
Yoteizan is a symmetrical andesitic-to-dacitic stratovolcano with a Fuji-like profile the forms a prominent landmark NW of Toya caldera. Its summit is truncated by a 700-m-wide crater that is cut on its NW rim by overlapping smaller craters. Deep radial gullies cut the flanks. The latest eruption from the main edifice took place about 5000-6000 years ago. Hangetsu-ko (Half Moon Lake), a tuff cone on the lower NW flank, was estimated from stratigraphic evidence to have erupted about 3000 years ago.
— Smithsonian Institution, Global Volcanism Program
2 Recorded Eruptions
| Year | VEI | Type | Area |
|---|---|---|---|
| 1050 BCE | — | Confirmed Eruption | NW flank (Hangetsu-ko) |
| 3550 BCE | — | Confirmed Eruption | — |
Real-Time Data
USGS Alert Level
Thermal Anomalies
Frequently Asked Questions About Yoteizan
Is Yoteizan an active volcano?+
Yoteizan is not currently classified as active. Its activity evidence is listed as "Eruption Dated." The last known eruption was in 1050 BCE. However, no volcano is ever considered permanently extinct.
When did Yoteizan last erupt?+
The most recent recorded eruption of Yoteizan occurred in 1050 BCE. The eruption was classified as a "Confirmed Eruption." Yoteizan has 2 recorded eruptions in total.
How high is Yoteizan?+
Yoteizan has a summit elevation of 1,888 meters (6,195 feet) above sea level. At 1,888 meters, it is a moderately sized volcanic peak, roughly comparable to Mount Vesuvius (1,281m).
What type of volcano is Yoteizan?+
Yoteizan 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 Yoteizan located?+
Yoteizan is located in Japan, in the Northwestern Pacific Volcanic Regions. More specifically, it lies within the Northeast Japan Volcanic Arc. Its exact coordinates are 42.827° latitude, 140.812° longitude.
Is it safe to visit Yoteizan?+
Yoteizan 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.
