Bounty Seamount

Bounty Seamount
Summit depth	420 metres (1,380 ft)
Location
Coordinates	25°11′S 129°23′W[1]

Bounty Seamount is a seamount in the Pacific Ocean, which reaches a depth of 420 metres (1,380 ft)[2] or 450 metres (1,480 ft). It is about 3,950 metres (12,960 ft) high.[3]

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.[4] These seamounts were discovered in 1989.[2]

Bounty has a conical shape, with three summit cones and several rift zones. Pillow lavas and hyaloclastite cover its slopes,[5] and parasitic vents can be observed as well.[6] 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.[7] Bounty has erupted rocks with compositions of alkali basalt, trachyandesite and trachyte.[8]

Eruption history

Bounty Seamount was formed in several stages,[2] and it could have developed over a time of 58,000 years.[6] Alkali basalts from Bounty have been dated by potassium-argon dating to be 344,000 ± 32,000 years before present.[9] Nevertheless, traces of recent volcanic activity and of hydrothermal venting have been found.[2]

This hydrothermal venting manifests itself by the release of low-temperature fluids and the formation of iron-rich crusts.[2] Temperatures of vented fluids amount to 14–19 °C (57–66 °F).[10]

References

1. 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.
2. Scholten et al. 2004, p. 376.
3. Binard, Hékinian & Stoffers 1992, p. 253.
4. Guillou, Garcia & Turpin 1997, p. 241.
5. Binard, Hékinian & Stoffers 1992, p. 259.
6. Hekinian et al. 2003, p. 229.
7. Hekinian et al. 2003, p. 228.
8. Binard, Hékinian & Stoffers 1992, p. 257.
9. Guillou, Garcia & Turpin 1997, p. 243.
10. 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.