230Th-238 U disequilibrium in East Scotia backarc basalts: Implications for slab contributions

Geology

Volumn 31, Issue 8, 2003, Pages 693-696

  Fretzdorff, S ^a   Haase, K M ^a   Leat, P T ^b   Livermore, R A ^b   Garbe Schonberg C D ^a   Fietzke, J ^a   Stoffers, P ^a  

^a UNIVERSITY OF KIEL   (Germany)

^b BRITISH ANTARCTIC SURVEY   (United Kingdom)

Author keywords

Aqueous fluids; Backarc; East Scotia Ridge; Sediment melts; U series isotopes

Indexed keywords

SEDIMENT MELT;

COMPOSITION; ISOTOPES; SEDIMENTS;

BASALT;

AQUEOUS SOLUTION; BACKARC BASIN; CHEMICAL COMPOSITION; LAVA; MID-OCEAN RIDGE BASALT; SPREADING CENTER; THORIUM ISOTOPE; URANIUM ISOTOPE;

SCOTIA SEA;

EID: 0141792102     PISSN: 00917613     EISSN: None     Source Type: Journal    
DOI: 10.1130/G19469.1     Document Type: Article

References (32)

1. Barker, P.F., 1995, Tectonic framework of the East Scotia Sea, in Taylor, B., ed., Backarc basins: Tectonics and magmatism: New York, Plenum Press, p. 281-314.
2. Barker, P.F., and Lawver, L.A., 1988, South American Antarctic plate motion over the past 50 Myr, and the evolution of the South American-Antarctic Ridge: Geophysical Journal, v. 94, p. 377-386.
3. Beattie, P., 1993, Uranium-thorium disequilibria and partitioning on melting of garnet peridotite: Nature, v. 363, p. 63-65.
4. 230Th disequilibrium data: Nature, v. 384, p. 231 235.
5. Brenan, J.M., Shaw, H.F., Ryerson, F.J., and Phinney, D.L., 1995, Mineral-aqueous fluid partitioning of trace element, at 900 °C and 2.0 GPa: Constraints on the trace element chemistry of mantle and deep crustal fluids: Geochimica et Cosmochimica Acta, v. 59, p. 3331-3350.
6. Brett, C.P., 1977, Seismicity of the South Sandwich Islands region: Royal Astronomical Society Geophysical Journal, v. 51, p. 453-464.
7. Bruguier, N.J., and Livermore, R.A., 2001, Enhanced magma supply at the southern East Scotia Ridge: Evidence for mantle flow around the subducting slab?: Earth and Planetary Science Letters, v. 191. p. 129 144.
8. Cohen, A.S., and O'Nions, R.K., 1993, Melting rates beneath Hawaii: Evidence from uranium series isotopes in recent lavas: Earth and Planetary Science Letters, v. 120, p. 169-175.
9. Elliott, T., Plank, T., Zindler, A., White, W., and Bourdon, B., 1997, Element transport from slab to volcanic front at the Mariana arc: Journal of Geophysical Research, v. 102, p. 14,991-15,019.
10. Fietzke, J., Garbe-Schönberg, C.-D., Scholten, J., and Arpe, T., 2000, Determination of protactinium and thorium isotopes by high resolution sectorfield ICP mass spectrometry: 2000 Winter Conference on Plasma Spectrochemistry: Fort Lauderdale, Florida, ICP Information Newsletter, p. 292-293.
11. Fretzdorff, S., Livermore, R.A., Devey, C.W., Leat, P.T., and Stoffers, P., 2002, Petrogenesis of the back-arc East Scotia Ridge, South Atlantic Ocean: Journal of Petrology, v. 43. p. 1435-1467.
12. Gill, J.B., and Williams, R.W., 1990, Th isotope and U-series studies of subduction-related volcanic rocks: Geochimica et Cosmochimica Acta, v. 54, p. 1427 1442.
13. 230Th disequilibrium: Earth and Planetary Science Letters, v. 109. p. 255 272.
14. Hawkesworth, C.J., Turner, S.P., McDermott, F., Peate, D.W., and van Calsteren, P., 1997a, Elemental U and Th variations in island arc rocks: Implications for U-series isotopes: Chemical Geology, v. 139. p. 207-221.
15. Hawkesworth, C.J., Turner, S.P., McDermott, F., Peate, D.W., and van Calsteren, P., 1997b, U-Th isotopes in arc magmas: Implications for element transfer from the subducted crust: Science, v. 276, p. 551-555.
16. Hofmann, A.W., Jochum, K.P., Seufert, M., and White, W.M., 1986, Nb and Pb in oceanic basalts: New constraints on mantle evolution: Earth and Planetary Science Letters, v. 79, p. 33 45.
17. Johnson, M.C., and Plank, T., 1999, Dehydration and melting experiments constrain the fate of subducted sediments: Geochemistry, Geophysics, Geosystems, v. 1. p. 1999GC000014.
18. Leat, P.T., Livermore, R.A., Millar, I.L., and Pearce, J.A., 2000, Magma supply in back-arc spreading centre segment E2. East Scotia Ridge: Journal of Petrology. v. 41, p. 845-866.
19. Livermore, R., Larter, R.D., Cunningham, A.D., Vanneste, L., and Hunter, R.J., 1995, Hawaii-MRI sonar survey of the East Scotia Ridge: BRIDGE Newsletter, v. 8, p. 51-53.
20. Livermore, R., Cunningham, A., Vanneste, L., and Latter, R., 1997, Subduction influence on magma supply at the East Scotia Ridge: Earth and Planetary Science Letters, v. 150, p. 261-275.
21. 238U disequilibrium systematics in lavas from three hot spot regions: Hawaii, Prince Edward and Samoa: Geochimica et Cosmochimica Acta, v. 48, p. 315 324.
22. Pearce, J.A., Leat, P.T., Barker, P.F., and Millar, I.L., 2001, Geochemical tracing of Pacific-to-Atlantic upper-mantle flow through the Drake Passage: Nature, v. 410, p. 457 461.
23. Peate, D.W., Kokfelt, T.F., Hawkesworth, C.J., van Calsteren, P.W., Hergt, J.M., and Pearce, J.A., 2001, U-series isotope data on Lau Basin glasses: The role of subduction-related fluids during melt generation in back-arc hasins: Journal of Petrology, v. 42, p. 1449-1470.
24. Pelayo, A.M., and Wiens, D.A., 1989, Seismotectonics and relative plate motions in the Scotia Sea region: Journal of Geophysical Research, v. 94, p. 7293-7320.
25. Plank, T., and Langmuir, C.H., 1998, The chemical composition of subducting sediment and its consequences for the crust and mantle: Chemical Geology. v. 145, p. 325-394.
26. Saunders, A.D., and Tarney, J., 1979. The geochemistry of basalts from a back-arc spreading centre in the East Scotia Sea: Geochimica et Cosmochimica Acta, v. 43, p. 555 -572.
27. Sclater, J.G., Bowin, C.O., Hey, R., Hoskins, H., Peirce, J., Phillips, J., and Tapscott, C., 1976. The Bouvet triple junction: Journal of Geophysical Research, v. 81, p. 1957-1869.
28. Spiegelman, M., and Elliott, T., 1993, Consequences of melt transport for uranium series disequilibrium in young lavas: Earth and Planetary Science Letters, v. 118, p. 1-20.
29. Stern, R.J., Lin, P.-N., Morris, J.D., Jackson, M.C., Fryer, P., Bloomer, S.H., and Ito, E., 1990, Enriched back-arc basin basalts from the northern Mariana Trough: Implications for the magmatic evolution of bark-arc basins: Earth and Planetary Science Letters, v. 100, p. 210-225.
30. 238U) of young matic volcanic rocks from Nicaragua and Costa Rica and the influence of flux melting on U-series systematics of arc lavas: Geochimica et Cosmochimica Acta, v. 66, p. 4287-4309.
31. 230Th disequilibria, magma petrogenesis, and flux rates beneath the depleted Tonga-Kermadec island arc: Geochimica et Cosmochimica Acta. v. 61, p. 4855-4884.
32. Vanneste, L., and Larter, R.D., 2002, Sediment subduction, subduction erosion and strain regime in the northern South Sandwich forearc: Journal of Geophysical Research, v. 107, DOI 10.1029/2001JB000396, p. 2149.