About Yokoatejima
Yokoatejima is a stratovolcano(es) rising to 495 meters (1,624 feet) in Japan's Western Pacific Volcanic Regions. Its last known eruption was in 1835 CE. The volcano has produced 1 recorded eruption, with a maximum Volcanic Explosivity Index (VEI) of 2.
Geography & Climate
Yokoatejima is located in Japan, within the Ryukyu Volcanic Arc of the broader Western Pacific Volcanic Regions. Situated at 28.80° N, 129.00° E in the Northern Hemisphere, the volcano lies within a subtropical climate zone. At just 495 meters above sea level, Yokoatejima is a relatively low-elevation volcanic feature. Despite its modest height, it remains an active geological formation with the same underlying magmatic processes as its taller counterparts. 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
Yokoatejima 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 Yokoatejima, 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
Yokoatejima has 1 recorded eruption in the geological database, spanning from 1835 CE to 1835 CE. The most powerful recorded event was an explosive event producing ash plumes up to several kilometers in 1835 CE, reaching VEI 2 on the Volcanic Explosivity Index.
GVP Reference Summary
Yokoatejima is a small, 3.5-km-long, dumbbell-shaped island NW of Amami Oshima Island at the SW end of the Tokara island chain. Two peaks, Higashimine on the east and Nishimine on the west, form the andesitic island. Higashimine, the high point of the island, has a steep-walled, well-preserved summit crater. An arcuate ridge east of Yokoate-jima appears to be part of 7 x 10 km submarine caldera, with Yokoatejima and Kaminonejima to the NNE being post-caldera cones (Nakano et al., 2001-). Yokoatesho (Yokoate Reef) and Kaminone Kaikyu (Kaminone Knoll) lie to NNW and NE of Yokoatejima, respectively. Historical documents at the end of the Edo Period mention ash plumes from Yokoatejima.
— Smithsonian Institution, Global Volcanism Program
1 Recorded Eruption
| Year | VEI | Type | Area |
|---|---|---|---|
| 1835 | 2 | Confirmed Eruption | — |
Real-Time Data
USGS Alert Level
Thermal Anomalies
Frequently Asked Questions About Yokoatejima
Is Yokoatejima an active volcano?+
Yokoatejima is classified as active based on credible evidence of past eruptions. Although its last known eruption was in 1835 CE, volcanologists consider it capable of erupting again.
When did Yokoatejima last erupt?+
The most recent recorded eruption of Yokoatejima occurred in 1835 CE with a Volcanic Explosivity Index (VEI) of 2. The eruption was classified as a "Confirmed Eruption." Yokoatejima has 1 recorded eruption in total.
How high is Yokoatejima?+
Yokoatejima has a summit elevation of 495 meters (1,624 feet) above sea level. At 495 meters, it is a relatively low-elevation volcano.
What type of volcano is Yokoatejima?+
Yokoatejima is classified as a Stratovolcano(es). Stratovolcano(es) volcanoes have distinct geological characteristics that set them apart from other volcanic types.
Where is Yokoatejima located?+
Yokoatejima is located in Japan, in the Western Pacific Volcanic Regions. More specifically, it lies within the Ryukyu Volcanic Arc. Its exact coordinates are 28.797° latitude, 128.997° longitude.
Is it safe to visit Yokoatejima?+
Yokoatejima 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.
