Skip to main content
← Back to map
⇄ Compare

Myōjin-shō

Myojinsho

Caldera · Japan · 11m

Steam emission from the blocky summit of a lava dome formed during a submarine eruption at the Beyonesu Rocks vent of the Myojinsho caldera in 1952. This 22 September photo was taken six days after the dome began to breach the sea surface. Later that day the eruption became highly explosive and the dome was destroyed. Three cycles of dome growth and destruction occurred until October 1953.
Steam emission from the blocky summit of a lava dome formed during a submarine eruption at the Beyonesu Rocks vent of the Myojinsho caldera in 1952. This 22 September photo was taken six days after the dome began to breach the sea surface. Later that day the eruption became highly explosive and the dome was destroyed. Three cycles of dome growth and destruction occurred until October 1953. · Photo: Photo courtesy of Helen Foster, 1952 (U.S. Geological Survey). · Wikimedia Commons
Type
Caldera
Country
Japan
Region
Northwestern Pacific Volcanic Regions / Izu Volcanic Arc
Elevation
11m
Coordinates
31.888, 139.918
Last eruption
1970
Tectonic setting
Subduction zone / Oceanic crust (< 15 km)
Landform
Caldera
Major rock type
Dacite
Geological summary

Beyonesu Rocks are part of the barely exposed rim of the largely submarine Myojinsho caldera. Formation of the 8-9 km wide caldera was followed by construction of a large (2.6 km3) lava dome and/or lava flow complex on the caldera floor, originally located at a depth of 1,000-1,100 m. Most eruptions recorded since the late-19th century have occurred from the dacitic post-caldera Myojinsho lava dome on the NE caldera rim. Deposits from submarine pyroclastic flows associated with growth of the dome cover it and extend both into the NE part of the caldera and down its outer slopes. An explosive submarine eruption from Myojinsho in 1952 destroyed a Japanese research vessel, killing all 31 on board. Submarine eruptions have also been observed from other points on the caldera rim and outside of the caldera. The Beyonesu Rocks were named after the French warship the Bayonnaise, which was surveying volcanic islands south of Tokyo Bay in 1850.

From Wikipedia

Myōjin-shō (明神礁) is a submarine volcano located about 450 kilometers south of Tokyo on the Izu-Ogasawara Ridge in the Izu Islands. Volcanic activity has been detected there since 1869. Since then it has undergone more eruptions, the most powerful of which resulted in the appearance and disappearance of a small island.

Wikipedia · CC BY-SA · Read full article →

Eruption history

Summary (VEI over time)
Click a bar to see individual eruptions
1869~1884 · 2 eruptions · max VEI 01884~1900 · 1 eruptions · max VEI 21900~1915 · 2 eruptions · max VEI 11931~1946 · 1 eruptions · max VEI 01946~1961 · 8 eruptions · max VEI 21961~1977 · 2 eruptions · max VEI 21977~1992 · 7 eruptions · max VEI 02008~2023 · 2 eruptions · max VEI ?18691900194619772008

Detailed timeline

  1. 2023VEI ?Observed
    2023-01-26 – 2023-01-26
  2. 2018VEI ?Observed
    2018-03-24 – 2018-03-24
  3. 1988VEI 0Geological estimate
    1988-03-18 – 1988-03-19
    Myojinsho
  4. 1987VEI 0Geological estimate
    1987-10-21 – 1987-12-09
    Myojinsho
  5. 1986VEI 0Geological estimate
    1986-10-24 – 1986-10-24
    Myojinsho
  6. 1983VEI 0Geological estimate
    1983-05-12 – Ongoing
    Myojinsho
  7. 1982VEI 0Geological estimate
    1982-08-10 – Ongoing
    Myojinsho
  8. 1980VEI 0Geological estimate
    1980-11-15 – 1980-12-23
    Myojinsho
  9. 1979VEI 0Geological estimate
    1979-07-13 – Ongoing
    Myojinsho
  10. 1971VEI 0Geological estimate
    1971-03-18 – Ongoing
  11. 1970VEI 2Observed
    1970-01-29 – 1970-06-16
    Myojinsho
  12. 1960VEI 2Observed
    1960-07-21 – Ongoing
    Myojinsho
  13. 1959VEI 0Observed
    1959-07-02 – Ongoing
  14. 1958VEI 0Observed
    1958-07-02 – Ongoing
  15. 1957VEI 0Observed
    1957-05-02 – Ongoing
  16. 1955VEI 0Observed
    1955-06-25 – Ongoing
    4 km north of Bayonnaise Rocks
  17. 1954VEI 0Observed
    1954-11-04 – 1954-11-05
    Myojinsho
  18. 1952VEI 2Observed
    1952-09-16 – 1953-10-16
    Myojinsho
  19. 1946VEI 2Observed
    1946-02-04 – Ongoing
    Island at 31.95 N 140.02 E
  20. 1934VEI 0Observed
    1934-05 – Ongoing
    9 km E of Bayonnaise Rocks
  21. 1915VEI 0Observed
    1915-02 – 1915-07
    11 km east, 19 km NE, 4 km SW
  22. 1906VEI 1Observed
    1906-04-07 – 1906-04-14
    9-15 km SE of Bayonnaise Rocks
  23. 1896VEI 2Observed
    1896 – Ongoing
    14 km north of Bayonnaise Rocks
  24. 1871VEI 0Geological estimate
    1871 – Ongoing
    Volcano Uncertain
  25. 1869VEI 0Geological estimate
    1869-05-06 – Ongoing
    Volcano Uncertain

External links

⚠ For reference only. Not for emergency response.