Oshima Volcano

Izu-Oshima volcano, 伊豆大島 Izu-ōshima) is the northernmost of the Izu islands of Japan, and one of the world's most active volcanoes. It is a mostly submerged stratovolcano that forms an 11 x 13 km island.
Oshima erupts very frequently, on average every 1-3 years, but has been quiet since 1990, which is an unusual long interval compared to its activity in historic times.
Eruptions at Oshima volcano occur from both summit and flank vents and its lavas are relatively fluid. The eruptions often produce lava fountains, strombolian activity, lava flows and the formation of lava lakes.
Oshima volcano eruptions: 1990, 1987-88, 1986, 1974, 1971, 1970, 1970, 1969, 1968, 1968, 1967, 1965-66, 1962-65, 1961(?), 1959-60, 1959, 1958, 1957, 1956, 1956(?), 1953-54, 1950-51, 1940, 1939, 1939, 1938, 1937, 1935, 1934, 1934(?), 1933, 1928, 1922-23, 1920(?), 1919, 1915, 1914, 1912-13, 1910, 1876-77, 1870, 1868?, 1846, 1837-38, 1827, 1822-24, 1803, 1792, 1789, 1783-86, 1777-79, 1695, 1684-90, 1636-38, 1612-13, 1600-01, 1588, 1552, 1527, 1442, 1421, 1416, 1415, 1338, 1267, 1112, 936, 886, 854(?), 751, 684(?), 681(?), 680(?), 654, 630, 605
Latest nearby earthquakes
Date and Time | Mag / Depth | Distance / Location | |||
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Jun 15, 10:20 pm (GMT +9) | 1.9 12 km | 19 km (12 mi) to the S | ![]() | Info | |
Jun 15, 08:32 pm (GMT +9) | 1.3 7 km | 19 km (12 mi) to the S | ![]() | Info | |
Jun 15, 07:02 pm (GMT +9) | 2.1 12 km | 20 km (12 mi) to the S | ![]() | Info | |
Jun 15, 09:22 am (GMT +9) | 2.3 15 km | 20 km (12 mi) to the S | ![]() | Info | |
Saturday, June 14, 2025 GMT (3 quakes) | |||||
Jun 15, 01:04 am (GMT +9) | 0.8 14 km | 18 km (11 mi) to the S | ![]() | Info | |
Jun 14, 05:52 pm (GMT +9) | 1.5 13 km | 17 km (10.7 mi) to the S | ![]() | Info | |
Jun 14, 05:01 pm (GMT +9) | 1.3 13 km | 17 km (10.5 mi) to the S | ![]() | Info | |
Tuesday, June 10, 2025 GMT (1 quake) | |||||
Jun 10, 08:33 pm (GMT +9) | 3.2 14 km | 19 km (12 mi) to the S | ![]() | Info | |
Sunday, June 8, 2025 GMT (2 quakes) | |||||
Jun 9, 05:28 am (GMT +9) | 2.6 12 km | 28 km (18 mi) to the SW | ![]() | Info |
Background
from Smithsonian / GVP volcano information:Oshima volcano in Sagami Bay, east of the Izu Peninsula, is the northernmost of the Izu Islands. The broad, low stratovolcano forms an 11 x 13 km island and was constructed over the remnants of three dissected stratovolcanoes.
It is capped by a 4-km-wide caldera with a central cone, Mihara-yama, that has been the site of numerous historical eruptions. More than 40 parasitic cones are located within the caldera and along two parallel rift zones trending NNW-SSE. Although Oshima is a dominantly basaltic volcano, strong explosive activity has occurred at intervals of 100-150 years throughout the past few thousand years. Historical activity at Oshima dates back to the 7th century AD.
Oshima Volcano Photos


Significant volcanic eruptions: Oshima volcano
Additionally, there are 9 uncertain or discredited eruptions from Oshima volcano.
Date | Note | VEI | Deaths | Damage | |
---|---|---|---|---|---|
Mihara-yama (1987 summit crater) Historical obs./docs. | 2 | ||||
Mihara-yama Historical obs./docs. | 2 | ||||
Mihara-yama, N part and NW of caldera Historical obs./docs. | 3 | ||||
1986 Nov 15 (eruption | Historical obs./docs. | 3 | 1 | Info | |
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
?? | Uncertain Eruption | ? | |||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
1957 Oct 13 (eruption | Historical obs./docs. | 2 | 1 | Info | |
?? | Uncertain Eruption | 1? | |||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
1953 Oct 5 (eruption | Historical obs./docs. | 1 | 1 | Info | |
Mihara-yama, south rim Historical obs./docs. | 2 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1? | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 0 | ||||
Mihara-yama Historical obs./docs. | 0 | ||||
?? | Uncertain Eruption | ? | |||
Mihara-yama Historical obs./docs. | 0 | ||||
Mihara-yama Historical obs./docs. | 0 | ||||
Mihara-yama Historical obs./docs. | 2 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 0 | ||||
?? | Uncertain Eruption | ? | |||
Mihara-yama Historical obs./docs. | 2 | ||||
Mihara-yama Historical obs./docs. | 2 | ||||
Mihara-yama Historical obs./docs. | 1 | ||||
Mihara-yama Historical obs./docs. | 1 |
Eruptions of Oshima volcano
A major eruption from Izu-Oshima volcano in 1986 produced spectacular lava fountains up to 1600 m height and a 16-km-high subplinian eruption column. More than 12,000 persons were evacuated from the island.
Tall lava fountains:
The 1968 Oshima lava fountain is the second highest ever (photographically) recorded lava fountain from a volcano. The highest is the 1500-2000 m tall lava fountain from the Voragine on Etna volcano on 4 September 1999, the third the 1000-1200 m tall lava fountain from Etna's SE crater during the paroxysm on 23 May 2000.
For comparison, the tallest lava fountains observed on Hawaii were about 590 m tall from Kilauea Iki on 21 November 1959. The specacular lava fountains from Pu'u O'o during 1983-85 reached up to 500 m.
Oshima Volcano FAQ
+When was the last eruption of Oshima volcano?
The last confirmed eruption of Oshima occurred in 1990.
+How often does Oshima volcano erupt?
Since 654 AD, Oshima volcano has had at least 63 historically documented eruptions. This means that it erupts on average every 21.8 years.
Many eruptions of Oshima have lasted more than one year. In total, the volcano has been in eruption during 88 out of 1371 years until now. In other words, Oshima has been active at least one in 15.6 years on average. Note that this value is likely an underestimate, because the known history of eruptions from Oshima is likely incomplete, especially further back in time.
+How active is Oshima volcano at present?
Oshima volcano is very active: Since 1900, it has had 40 eruptions, and been active during 40 years out of 126 as of now. This means, Oshima has been in eruption one in 3.2 years on average. The last eruption was in 1990 and ended 35 years ago.
+When was the largest eruption of Oshima volcano?
The largest eruption of Oshima volcano in historic times occurred in 1421 AD. It ranks as a sub-plinian eruption with a magnitude 4 on the VEI (Volcanic Explosivity Index) scale.
Latest satellite images
Oshima Volcano Maps





















