The launch of a new GVP website is scheduled for Monday, May 20, 2013.
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Country: | United States | |
| Subregion Name: | Samoan Islands | ||
| Volcano Number: | 0404-01= | ||
| Volcano Type: | Shield volcanoes | ||
| Volcano Status: | Historical | ||
| Last Known Eruption: | 1866 | ||
| Summit Elevation: | 639 m | 2,096 feet | |
| Latitude: | 14.175°S | 14°10'30"S | |
| Longitude: | 169.618°W | 169°37'6"W | |
| 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. The islands are formed by two eroded, coalescing basaltic shield volcanoes whose slopes dip to the east and west. Steep cliffs up to 600-m high truncate the northern and southern sides of the islands. The narrow, steep-sided ridge forming the eastern tip of Ofu Island consists of a dike complex. The shield volcano on Ofu is cut on the north by the A'ofa caldera; bathymetry suggests that a caldera may also exist on the Sili shield volcano of Olosega. The Nu'utele tuff cone, forming a small crescent-shaped island immediately off the west end of Ofu Island, is Holocene in age. A submarine eruption took place in 1866 at the opposite end of the two islands, 3 km SE of Olosega, along the ridge connecting Olosega with Ta'u Island. | |||
