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Oshima-Oshima

Photo of this volcano
  • Japan
  • Stratovolcano
  • 1790 CE
  •  
  • Country
  • Primary Volcano Type
  • Last Known Eruption
  •  
  • 41.51°N
  • 139.367°E

  • 732 m
    2402 ft

  • 285010
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Bulletin Report: March 1996 (BGVN 21:03) Citation IconCite this Report

Earthquakes and tremor detected

Volcanic earthquakes and tremors were detected near the end of March by instruments maintained by Hokkaido University.

This small island 55 km W of Hokkaido in the Japan Sea consists of two coalescing volcanoes. An eruption in August 1741 produced heavy ashfall on the Hokkaido mainland. A violent explosion and landsliding from the Nishi-yama cone accompanied a large tectonic earthquake and a major tsunami that killed 1,475 people, most on the W coast of the Oshima Peninsula. Subsequent eruptions through early 1742 produced a new central cone and lava flows. Minor explosive activity was documented in 1759, 1786, and 1790.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.

The Global Volcanism Program has no Weekly Reports available for Oshima-Oshima.

Bulletin Reports - Index

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

03/1996 (BGVN 21:03) Earthquakes and tremor detected




Information is preliminary and subject to change. All times are local (unless otherwise noted)


March 1996 (BGVN 21:03) Citation IconCite this Report

Earthquakes and tremor detected

Volcanic earthquakes and tremors were detected near the end of March by instruments maintained by Hokkaido University.

This small island 55 km W of Hokkaido in the Japan Sea consists of two coalescing volcanoes. An eruption in August 1741 produced heavy ashfall on the Hokkaido mainland. A violent explosion and landsliding from the Nishi-yama cone accompanied a large tectonic earthquake and a major tsunami that killed 1,475 people, most on the W coast of the Oshima Peninsula. Subsequent eruptions through early 1742 produced a new central cone and lava flows. Minor explosive activity was documented in 1759, 1786, and 1790.

Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Eruptive History

There is data available for 5 confirmed Holocene eruptive periods.

1790 Jan (?) Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Nishi-yama
1790 Jan (?) - Unknown Evidence from Observations: Reported

List of 2 Events for Episode 1 at Nishi-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
1790 Jan
(?)
   - - - - VEI (Explosivity Index)

[ 1786 ] Uncertain Eruption

Episode 1 | Eruption Episode Nishi-yama
1786 - Unknown Evidence from Unknown

List of 2 Events for Episode 1 at Nishi-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Volcanic "smoke"
1786    - - - - VEI (Explosivity Index)

1759 Aug 19 Confirmed Eruption Max VEI: 2

Episode 1 | Eruption Episode Nishi-yama
1759 Aug 19 - Unknown Evidence from Observations: Reported

List of 3 Events for Episode 1 at Nishi-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion weak or small
   - - - -    - - - - Ash
1759 Aug 19    - - - - VEI (Explosivity Index)

1741 Aug 18 (?) - 1742 May Confirmed Eruption Max VEI: 4

Episode 1 | Eruption Episode Nishi-yama
1741 Aug 18 (?) - 1742 May Evidence from Observations: Reported

List of 11 Events for Episode 1 at Nishi-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion violent, strong, or large
   - - - -    - - - - Lava flow
   - - - -    - - - - Cinder Cone
   - - - -    - - - - Avalanche
   - - - -    - - - - Ash
   - - - -    - - - - Tsunami
   - - - -    - - - - Edifice Destroyed Collapse/avalanche
   - - - -    - - - - Property Damage
1741 Aug 18
(?)
   - - - - VEI (Explosivity Index)
1741 Aug 23    - - - - Fatalities
1741 Aug 29    - - - - VEI (Explosivity Index)

0250 ± 150 years Confirmed Eruption  

Episode 1 | Eruption Episode Nishi-yama
0250 ± 150 years - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 2 Events for Episode 1 at Nishi-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0800 BCE ± 100 years Confirmed Eruption  

Episode 1 | Eruption Episode Nishi-yama
0800 BCE ± 100 years - Unknown Evidence from Isotopic: 14C (uncalibrated)

List of 2 Events for Episode 1 at Nishi-yama

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
Deformation History

There is no Deformation History data available for Oshima-Oshima.

Emission History

There is no Emissions History data available for Oshima-Oshima.

GVP Map Holdings

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.

Smithsonian Sample Collections Database

The following 2 samples associated with this volcano can be found in the Smithsonian's NMNH Department of Mineral Sciences collections, and may be availble for research (contact the Rock and Ore Collections Manager). Catalog number links will open a window with more information.

Catalog Number Sample Description Lava Source Collection Date
NMNH 112974 Hornblende Basalt -- --
NMNH 112975 Olivine Basalt -- --
External Sites