| Bounty Seamount | |
|---|---|
| Summit depth | 420 metres (1,380 ft) |
| Location | |
| Coordinates | 25°11′S 129°23′W / 25.183°S 129.383°W / -25.183; -129.383 |
Bounty Seamount is a seamount in the Pacific Ocean, which reaches a depth of 420 metres (1,380 ft) or 450 metres (1,480 ft). It is about 3,950 metres (12,960 ft) high.
Geology and geomorphology
The seamount is part of a group of seamounts about 100 kilometres (62 mi) away from Pitcairn Island, which includes several small seamounts and the large Adams Seamount. These seamounts were discovered in 1989.
Bounty has a conical shape, with three summit cones and several rift zones. Pillow lavas and hyaloclastite cover its slopes, and parasitic vents can be observed as well. The volcano has a volume of about 310 cubic kilometres (74 cu mi) and has a width of 19 kilometres (12 mi) at its foot. Bounty has erupted rocks with compositions of alkali basalt, trachyandesite and trachyte.
Eruption history
Bounty Seamount was formed in several stages, and it could have developed over a time of 58,000 years. Alkali basalts from Bounty have been dated by potassium-argon dating to be 344,000 ± 32,000 years before present. Nevertheless, traces of recent volcanic activity and of hydrothermal venting have been found.
This hydrothermal venting manifests itself by the release of low-temperature fluids and the formation of iron-rich crusts. Temperatures of vented fluids amount to 14–19 °C (57–66 °F).
References
- Devey, C.W.; Lackschewitz, K.S.; Mertz, D.F.; Bourdon, B.; Cheminée, J.-L.; Dubois, J.; Guivel, C.; Hékinian, R.; Stoffers, P. (1 May 2003). "Giving birth to hotspot volcanoes: Distribution and composition of young seamounts from the seafloor near Tahiti and Pitcairn islands". Geology. 31 (5): 396. Bibcode:2003Geo....31..395D. doi:10.1130/0091-7613(2003)031<0395:GBTHVD>2.0.CO;2. ISSN 0091-7613.
- ^ Scholten et al. 2004, p. 376.
- Binard, Hékinian & Stoffers 1992, p. 253.
- Guillou, Garcia & Turpin 1997, p. 241.
- Binard, Hékinian & Stoffers 1992, p. 259.
- ^ Hekinian et al. 2003, p. 229.
- Hekinian et al. 2003, p. 228.
- Binard, Hékinian & Stoffers 1992, p. 257.
- Guillou, Garcia & Turpin 1997, p. 243.
- Scholten et al. 2004, p. 388.
Sources
- Binard, Nicolas; Hékinian, Roger; Stoffers, Peter (June 1992). "Morphostructural study and type of volcanism of submarine volcanoes over the Pitcairn hot spot in the South Pacific". Tectonophysics. 206 (3–4): 245–264. Bibcode:1992Tectp.206..245B. doi:10.1016/0040-1951(92)90379-K. ISSN 0040-1951.
- Guillou, Hervé; Garcia, Michael O.; Turpin, Laurent (September 1997). "Unspiked K-Ar dating of young volcanic rocks from Loihi and Pitcairn hot spot seamounts". Journal of Volcanology and Geothermal Research. 78 (3–4): 239–249. Bibcode:1997JVGR...78..239G. doi:10.1016/S0377-0273(97)00012-7. ISSN 0377-0273.
- Hekinian, R; Cheminée, J.L; Dubois, J; Stoffers, P; Scott, S; Guivel, C; Garbe-Schönberg, D; Devey, C; Bourdon, B; Lackschewitz, K; McMurtry, G; Le Drezen, E (March 2003). "The Pitcairn hotspot in the South Pacific: distribution and composition of submarine volcanic sequences" (PDF). Journal of Volcanology and Geothermal Research. 121 (3–4): 219–245. Bibcode:2003JVGR..121..219H. doi:10.1016/S0377-0273(02)00427-4. ISSN 0377-0273.
- Scholten, J. C.; Scott, S. D.; Garbe-Schönberg, D.; Fietzke, J.; Blanz, T.; Kennedy, C. B. (2004). "Hydrothermal Iron and Manganese Crusts from the Pitcairn Hotspot Region". Oceanic Hotspots. pp. 375–405. doi:10.1007/978-3-642-18782-7_13. ISBN 978-3-642-62290-8.