Boomerang Seamount
| Boomerang Seamount | |
|---|---|
 Approximate surface projection of Boomerang Seamount (blue outline). Nearby subsurface transform faults (grey) and fracture zones (orange), their probable extensions (light orange) and plate boundary (white, in this case the Southeast Indian Ridge) are also shown. | |
 | |
| Summit depth | 650 m (2,000 ft)[1] |
| Height | 1,100 m (3,600 ft)[1] |
| Location | |
| Location | Southern Indian Ocean, 18 kilometers northwest of Amsterdam Island |
| Coordinates | 37°43′16″S 77°49′30″E / 37.721°S 77.825°E |
| Country | France |
| Geology | |
| Type | Submarine volcano |
| Last eruption | December 1995 |
| History | |
| Discovery date | 1996[2] |
The Boomerang Seamount is an active submarine volcano, located 18 km (11 mi) northeast of Amsterdam Island, France. It was formed by the Amsterdam-Saint Paul hotspot and has a 2 km (1.2 mi) wide caldera that is 200 m (660 ft) deep. Hydrothermal activity occurs within the caldera.[1] The sampled rocks are basalt and picrite basalt.[2]
The seamount is located on the mainly undersea Amsterdam–Saint Paul Plateau of the Antarctic Plate,[1], which was mainly formed by the volcanic hotspot.[3] There is a magma chamber located at between 20–36 km (12–22 mi) depth below the nearby Amsterdam Island.[4] The plateau which extends north west towards the Nieuw Amsterdam Fracture Zone (Amsterdam Fracture Zone) and south to beyond the island of St Paul with its presently known active area being delimited by the St. Paul Fracture Zone,[5] is a 250 by 200 km (160 by 120 mi) feature of the sea floor near the Southeast Indian Ridge, which is an active spreading center between the Antarctic plate that the seamount lies on, and the Australian Plate.[6] Helium isotopic compositional studies are consistent with its formation from the combined effects of accretion at the mid-ocean ridge ridge and mantle plume activity of a hot spot.[6]This is either the Kerguelen hotspot or a potentially separate Amsterdam-Saint Paul hotspot but resolution of this issue is complicated by the recent volcanism on the island due to it being adjacent to the Southeast Indian Ridge.[7][3] Recent authors have favoured a separate Amsterdam and St. Paul hotspot.[5] Which ever hot spot is responsible is moving south as Île Amsterdam rocks are older than St. Paul rocks.[8] The Amsterdam–St. Paul Plateau while formed in the last 10 million years, started this formation beneath the Australian Plate so the island is built on the components of two tectonic plates.[9]
See also[edit]
References[edit]
- ^ a b c d Johnson et al. 2000, Abstract.
- ^ a b "Boomerang Seamount". Global Volcanism Program. Smithsonian Institution.
- ^ a b Bredow & Steinberger 2018, p. 128.
- ^ Kumar et al. 2023, 7. Conclusions.
- ^ a b Kumar et al. 2023, 2. Regional tectonic setting.
- ^ a b Doucet et al. 2004, p. 180.
- ^ Nobre Silva et al. 2013, p. 1177.
- ^ Doucet et al. 2004, p. 181.
- ^ Kumar et al. 2023, 6.3. Horizontal extent of the ASP plume magma supply, Fig. 6. Schematic diagram depicting interaction of the ASP plume and the SEIR since ~20 Ma in different stages.
Sources[edit]
- Johnson, K.T.M.; Graham, D.W.; Rubin, K.H.; Nicolaysen, K.; Scheirer, D.S.; Forsyth, D.W.; Baker, E.T.; Douglas-Priebe, L.M. (2000). "Boomerang Seamount: the active expression of the Amsterdam-St. Paul hotspot, Southeast Indian Ridge". Earth and Planetary Science Letters. 183: 245–259. Bibcode:2000E&PSL.183..245J. doi:10.1016/S0012-821X(00)00279-X.
- Bredow, E; Steinberger, B (16 January 2018). "Variable melt production rate of the Kerguelen hotspot due to long-term plume-ridge interaction". Geophysical Research Letters. 45 (1): 126–36. doi:10.1002/2017GL075822. hdl:10852/70913.
- Kumar, P.; Singha, P.; Ghosal, D.; Jacob, J.; Gupta, S. (2023). "Lithospheric architecture beneath the Amsterdam-St. Paul plateau, Southern Indian Ocean using the integrated gravity, magnetic and seismological study". Tectonophysics. 863: 229989. Bibcode:2023Tectp.86329989K. doi:10.1016/j.tecto.2023.229989.
- Doucet, S.; Weis, D.; Scoates, J.S.; Debaille, V.; Giret, A. (2004). "Geochemical and Hf–Pb–Sr–Nd isotopic constraints on the origin of the Amsterdam–St. Paul (Indian Ocean) hotspot basalts". Earth and Planetary Science Letters. 218 (1–2): 179–195. doi:10.1016/S0012-821X(03)00636-8.
- Nobre Silva, IG; Weis, D; Scoates, JS; Barling, J (2013). "The Ninetyeast Ridge and its relation to the Kerguelen, Amsterdam and St. Paul hotspots in the Indian Ocean". Journal of Petrology. 54 (6): 1177–210. doi:10.1093/petrology/egt009.
| Authority control databases: Geographic |
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