United States · Shield volcano
Ofu-Olosega
- Type
- Shield volcano
- Elevation
- 639m
- Last eruption
- 1866
- Type
- Shield volcano
- Country
- United States
- Region
- Southern Pacific / Samoan Hotspot Volcano Group
- Elevation
- 639m
- Coordinates
- -14.175, -169.618
- Last eruption
- 1866
- Tectonic setting
- Subduction zone / Oceanic crust (< 15 km)
- Landform
- Shield
- Major rock type
- Basalt / Picro-basalt
Geological summary
The two triangle-shaped islands of Ofu and Olosega in eastern Samoa, with a combined length of 6 km, are separated by a narrow strait.
Excerpt from the Global Volcanism Program, Smithsonian Institution · Read the full summary on GVP →
From Wikipedia
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. 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.
Wikipedia · CC BY-SA · Read full article →
Eruption history
1 recordedGlossaryRecord summary
- Confirmed eruptions
- 1
- Uncertain eruptions
- 0
- Span of confirmed record
- 1866 – 1866
- Largest confirmed eruption
- VEI 2 (1866)
- Confirmed eruptions since 1900
- 0
Detailed timeline
- 1866VEI 2Observed1866-09-12 – 1866-11-15Submarine vent 3 km SE of Olosega
Nearby volcanoes
External links
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