Overview of Ioto
Ioto is a caldera volcano located in Japan. The official record identifies 27 confirmed eruptions spanning from 850 BCE to 2025 CE. The volcano is situated at an elevation of 172 meters and is associated with a subduction zone tectonic setting, though the crustal thickness is not specified in the record.
Eruption History and Scale
The record of Ioto’s activity shows a consistent pattern of eruptions classified by the Volcanic Explosivity Index (VEI). The largest recorded event for Ioto is a VEI 1.0. The eruptions are distributed across different centuries, with the 20th and 21st centuries showing the highest frequency in the official count.
Timeline of Confirmed Eruptions
The following table lists representative confirmed eruptions from the official record. The total number of confirmed eruptions in the collection is 27, with 22 records omitted from this summary.
| Date | Activity Area | VEI | Evidence Method |
|---|---|---|---|
| 850 BCE (±50) | Motoyama | 1.0 | Isotopic: 14C (calibrated) |
| 1957-03-28 | Chidoriga-hara | 1.0 | Observations: Reported |
| 1982-03-09/10 | NW side (Idogahama beach) | 1.0 | Observations: Reported |
| 2015-08-07 | Kianohana Beach (N part of the island) | 1.0 | Observations: Reported |
| 2025-09-01/02 | Unspecified | 1.0 | Observations: Reported |
Recent Activity
The most recent confirmed eruption recorded for Ioto began on September 1, 2025, and ended on September 2, 2025. This event was classified as a VEI 1.0 and was reported through observational methods. Prior to this, significant activity was recorded in 2015 at Kianohana Beach, also classified as a VEI 1.0.
Frequently asked questions
How many eruptions has Ioto had?
The official record lists 27 confirmed eruptions for Ioto.
When was the most recent eruption?
The most recent confirmed eruption occurred in September 2025.
What is the largest recorded eruption of Ioto?
The largest recorded eruption is classified as a VEI 1.0.
Image credits
- Chisatos at ja.wikipedia — Wikimedia Commons source — Public domain
Sources and further context
Official datasets support the event-specific facts.