Suwanosejima is a stratovolcano located in Japan with an elevation of 796 meters, situated in a subduction zone on oceanic crust less than 15 kilometers deep. According to the Smithsonian Global Volcanism Program, the volcano has a total of 24 confirmed eruptions in its official record. Historical documentation spans from the 17th century CE into the 21st century CE, with activity frequently centered around the O-take activity area.
Chronology of Recorded Eruptions
The structured record of confirmed eruptions at Suwanosejima begins in the 1600 CE era and extends through multiple centuries. The earliest recorded eruption in the dataset occurred in the year 1600 CE with a Volcanic Explosivity Index (VEI) of 4.0, supported by tephrochronology correlation evidence. Over subsequent centuries, the frequency and scale of recorded events varied, with the O-take area hosting numerous reported eruptive phases.
The distribution of confirmed eruptions across centuries includes:
- 16th century CE: 1 recorded eruption
- 19th century CE: 5 recorded eruptions
- 20th century CE: 17 recorded eruptions
- 21st century CE: 1 recorded eruption
Notable historical events include an eruption starting on October 2, 1889, and ending on October 13, 1889, which reached a VEI of 4.0. During the 20th and 21st centuries, multiple eruptions with a VEI of 2.0 were documented through direct observation, such as an event starting on December 8, 1921, and ending on January 26, 1922; a long-span period starting on November 16, 1956, and concluding on May 16, 1984; and an eruption starting on October 23, 2004, which concluded on March 16, 2026.
Understanding Eruption Metrics and Records
The Volcanic Explosivity Index (VEI) provides a relative scale to describe the size of explosive volcanic eruptions based on volume of products, eruption cloud height, and qualitative observations. At Suwanosejima, recorded VEI values range up to a maximum of 4.0. The official record distinguishes between individual structured eruption periods and broader profile information; while specific structured eruption entries span up to March 16, 2026, the Smithsonian Global Volcanism Program profile lists a last known eruption year of 2026 as of the retrieval date in August 2026.
Frequently asked questions
How many eruptions has Suwanosejima had?
Suwanosejima has 24 confirmed eruptions recorded in the Smithsonian Global Volcanism Program database.
When did historical eruption records for Suwanosejima begin?
The earliest recorded eruption in the official dataset dates to 1600 CE.
What is the largest recorded VEI for Suwanosejima?
The largest recorded eruptions at Suwanosejima reached a Volcanic Explosivity Index (VEI) of 4.0.
Where is Suwanosejima located and what type of volcano is it?
Suwanosejima is located in Japan and stands at an elevation of 796 meters as a stratovolcano.
Image credits
- Umbra Lab, Inc. — Wikimedia Commons source — CC BY 4.0
Sources and further context
Official datasets support the event-specific facts.