Ofu-Olosega

Photo of this volcano
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 14.175°S
  • 169.618°W

  • 639 m
    2096 ft

  • 244010
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for Ofu-Olosega.

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

The Global Volcanism Program has no Bulletin Reports available for Ofu-Olosega.

Eruptive History


Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1866 Sep 12 1866 Nov 15 ± 5 days Confirmed 2 Historical Observations Submarine vent 3 km SE of Olosega

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.

Photo Gallery


Clouds drape the tops of the two triangle-shaped islands of Ofu (left) and Olosega (right) in eastern Samoa in this Space Shuttle image (with north to the upper left). The islands, 6 km in combined length, are separated by a narrow strait. They are formed by two eroded, coalescing basaltic shield volcanoes truncated by mostly submarine calderas. A submarine eruption took place in 1866 about 3 km SE of Olosega, along the ridge connecting Olosega with Ta'u Island.

NASA Space Shuttle image ISS002-E-6878, 2001 (http://eol.jsc.nasa.gov/).
See title for photo information.
A narrow strait (just left of center) separates the two triangle-shaped islands of Ofu (left) and Olosega (right) in eastern Samoa. The islands are formed by two eroded, coalescing basaltic shield volcanoes. The narrow, steep-sided ridge forming the western side of Ofu Island is cut by volcanic dikes, and an intrusive plug forms the sharp spire at the left on Ofu Island. A submarine eruption took place in 1866 at the far end of the two islands, 3 km SE of Olosega, along the ridge connecting Olosega with Ta'u Island.

Photo by Peter Craig, 1995 (U.S. National Park Service).
See title for photo information.

Smithsonian Sample Collections Database


There are no samples for Ofu-Olosega in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

Affiliated Sites