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    Ofu-Olosega

    Part of Manuʻa Islands

    Ofu and Olosega are parts of a volcanic doublet in the Manuʻa Islands, which is a part of American Samoa in the Samoan Islands. These twin islands, formed from shield volcanoes, have a combined length of 6 km and a combined area of 12 square kilometers (5 square miles).

    Ofu-Olosega, American Samoa. Ofu (left) and Olosega (right) are separated by a narrow strait just left of the center
    Ofu-Olosega, American Samoa. Ofu (left) and Olosega (right) are separated by a narrow strait just left of the center

    Peter Craig, National Park Service / Public domain

    Chart

    2 landforms

    Overview

    Ofu and Olosega are parts of a volcanic doublet in the Manuʻa Islands, which is a part of American Samoa in the Samoan Islands. These twin islands, formed from shield volcanoes, have a combined length of 6 km and a combined area of 12 square kilometers (5 square miles). Together, they have a population of about 500 people. Geographically, the islands are volcanic remnants separated by the narrow, 137-meter-wide (449-foot) Āsaga Strait, composed of shallow-water coral reef. Before 1970, people crossed between the two islands by waiting until low tide and then wading across the shallow water of the strait. Since 1970, there has been a bridge over the strait, providing a single-lane road that connects the two islands. The highest peak on Ofu Island is Mount Tumutumu (also called Tumu), at 491 m (1,611 ft). The highest peak on Olosega is Mount Piumafua, at 629 m (2,064 ft). The most recent volcanic eruption was in 1866, 3 km (1.9 mi) southeast of Olosega. Pre-historic artifacts discovered on Ofu by archaeological field work in the 1980s significantly furthered understanding of the ancient history of Ofu in particular, and the Samoa Islands and Polynesia in general. The artifacts include ceramics, adzes, and worked shell and bone pieces. Samples of red-slipped plainware ceramics were found that appear to have been crafted in the tradition of the Lapita culture. The field work, carried out by a team that included Pacific archaeology specialist Patrick Vinton Kirch, focused on a site called To'aga (site AS-13-1), a 2 km (1.2 mi) coastal stretch on the south coast of Ofu. Dating of the artifacts suggested that Ofu has been continuously inhabited by humans for about 3,000 years.

    From Wikipedia, CC BY-SA 4.0

    Census, cataloged

    • Major islands2
    • Minor islands0
    • Islets0
    • Rocks & skerries0

    Major islands

    2
    • Ofu

      Ofu

      Area
      7.2 km²
      High point
      487 m

      Ofu and Olosega are parts of a volcanic doublet in the Manuʻa Islands, which is a part of American Samoa in the Samoan Islands. These twin islands, formed from shield volcanoes, have a combined length of 6 km and a combined area of 12 square kilometers (5 square miles).

    • Olosega

      Area
      5.2 km²
      High point
      623 m

    Figures

    Comparative heights

    Sea level200 m400 m600 m800 m623 mOlosega487 mOfu
    High points by island, metres above sea level.

    Islands by area

    Sources

    Facts

    • Geometry, areas and high points: OpenStreetMap contributors (ODbL), Copernicus GLO-30, via Talus.
    • Wikidata
    • Wikipedia

    Photographs