Vailulu'u
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| Vailulu'u | |
|---|---|
 Location of American Samoa |
|
| Summit depth | 590 metres (1,940 ft) |
| Height | 4,200 m (13,800 ft) |
| Location | South Pacific Ocean |
| Coordinates | Coordinates: |
| Country | United States |
| Discovered | 1975 |
Vailulu'u is a volcanic seamount, not discovered until 1975, which rises 4200 m from the sea floor to a depth of 590 m about one-third of the way between Ta'u and Rose islands at the eastern end of the American Samoas. The basaltic seamount, is considered to mark the current location of the Samoan Hotspot. The summit of Vailulu'u contains a 2-km wide, 400-m-deep oval-shaped caldera. Two principal rift zones extend east and west from the summit, parallel to the trend of the Samoan hotspot, and a third less prominent rift extends southeast of the summit.
The rift zones and escarpments produced by mass wasting phenomena give the sea mount a star-shaped pattern. On July 10, 1973, explosions from Vailulu'u were recorded by SOFAR (hydrophone records of underwater acoustic signals). An earthquake swarm in 1995 may have been related to an eruption from the seamount. Turbid water above the summit shows evidence of ongoing hydrothermal plume activity.
Evidence released in 2006 suggest that Vailulu'u may breach the surface of the ocean and officially become an island during this century.[1]
[edit] Nafanua
Nafanua is an active underwater volcanic cone that has been growing inside the summit crater of Vailulu'u since 2001. In 2005 it was 300 m tall, but still 708 m below sea level.[2] It is best known as the site of 'Eel City,' a hydrothermal vent biological community consisting mainly of eels (rather than the usual invertebrates).[3]
[edit] References
- Smithsonian Institution Global Volcanism Program: Vailulu'u Retrieved 30 August 2007
- ^ Foxnews.com Emerging Ocean Volcano, Retrieved 30 August 2007
- ^ Staudigel, H. et al. (2006) Vailulu’u Seamount, Samoa: Life and death on an active submarine volcano, Proceedings of the National Academy of Sciences, volume 103 Number 17, pages 6448 to 6453, Retrieved 30 August 2007
- ^ Astrobiology Magazine: Extremes of Eel City Retrieved 30 August 2007
[edit] External links
- NOAA Ocean Explorer Vailulu'u 2005 Expedition, Retrieved 30 August 2007
- Vailulu'u web site, information about the Vailulu'u seamount
