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Iron and water losses from hydrous basalts contained in Au80Pd20 capsules at high pressure and temperature

Published online by Cambridge University Press:  05 July 2018

L. J. Hall ,
J. Brodie ,
B. J. Wood  and
M. R. Carroll
L. J. Hall
Affiliation:
Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK
J. Brodie
Affiliation:
Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK
B. J. Wood*
Affiliation:
Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK
M. R. Carroll
Affiliation:
Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK
*
*E-mail: [email protected]
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Abstract

We have performed experiments to determine the extents to which Fe and H2O are lost from hydrous basaltic melts contained in Au80Pd20 and graphite-lined Pt capsules at 0.7 –1 GPa and 1300–1350°C. All experiments were performed in the piston-cylinder apparatus. In order to minimize the possibility of rupture of the AuPd capsule and to control H2O loss we used a double-capsule method. The inner welded 2 mm diameter Au80Pd20 capsule was placed inside a welded 3 mm diameter Pt capsule, the intervening space being packed with hydrous sample. Loss of FeO* from the sample was found to be ≤4% relative in both the Au80Pd20 and graphite-lined Pt capsules in experiments of up to 24 h duration. Loss of H2O is greater and it depends on the oxidation state of the starting materials and the nature of the capsule. For starting mixes fired at 1 log fO2 unit above the quartz-fayalite-magnetite (QFM) buffer at 1 atm, H2O loss from Au80Pd20 capsules averaged 9% relative. Starting mixes fired at 1 log fO2 unit below the QFM buffer at 1atm lost, on average, 32% of their H2O when run in Au80Pd20 capsules at high pressure. All samples run in graphite-lined Pt capsules experienced dramatic H2O loss, averaging 52% relative, irrespective of initial oxidation state. We conclude that Au80Pd20 capsules are suitable for high-pressure hydrous melting experiments and that the sample loses very little Fe. In order to minimize H2O-loss, however, it is important that the starting materials be relatively oxidized.

Keywords

iron losswaterhydrous basaltAuPdcapsules
Type
Research Article
Information
Mineralogical Magazine , Volume 68 , Issue 1 , February 2004 , pp. 75 - 81
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2004

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Footnotes

**

Present address: Dipt. di Scienze della Terra, Università di Camerino, 62032 Camerino, Italy

References

Dixon, J.E., Stolper, E. and Holloway, J.R. (1995) An experimental study of water and carbon dioxide solubilities in mid-ocean ridge basaltic liquids I: Calibration and solubility models. Journal of Petrology, 36, 1607–1631.Google Scholar
Falloon, T.J. and Green, D.H. (1987) Anhydrous partial melting of MORB pyrolite and other peridotite compositions at 10 kbar–implications for the origin of primitive MORB glasses. Contributions to Mineralogy and Petrology, 37, 181–219.CrossRefGoogle Scholar
Grashoff, G.J., Pilkington, C.E. and Conti, C.W. (1983) The purification of hydrogen. Platinum Metals Review, 27, 157–169.Google Scholar
Green, D.H. (1976) Experimental testing of “equilibrium” partial melting of peridotite under watersaturated, high-pressure conditions. The Canadian Mineralogist, 14, 255–268.Google Scholar
Grove, T.L. (1981) Use of FePt alloys to eliminate the iron loss problem in 1 atm gas mixing experiments: Theoretical and practical considerations. Contributions to Mineralogy and Petrology, 78, 298–304.CrossRefGoogle Scholar
Hirose, K. and Kawamoto, T. (1995) Hydrous partial melting of lherzolite at 1 GPa: The effect of H2O on the genesis of basaltic magmas. Earth and Planetary Science Letters, 133, 463–473.CrossRefGoogle Scholar
Holloway, J.R., Pan, V. and Gudmundsson, G. (1992) High pressure fluid-absent melting experiments in the presence of graphite: Oxygen fugacity, ferric/ferrous ratio and dissolved CO2. European Journal of Mineralogy, 4, 105–114.CrossRefGoogle Scholar
Ito, K. and Kennedy, G.C. (1967) Melting and phase relations in a natural peridotite up to 40 kbar. American Journal of Science, 265, 519–538.CrossRefGoogle Scholar
Johannes, W., Bell, P.M., Boettcher, A.L., Chipman, D.W., Hays, J.F., Mao, H.K., Newton, R.C. and Seifert, F. (1971) An interlaboratory comparison of piston cylinder calibration using the albite breakdown. Contributions to Mineralogy and Petrology, 32, 24–38.CrossRefGoogle Scholar
Kawamoto, T. and Hirose, K. (1994) Au-Pd sample containers for melting experiments on iron and water bearing systems. European Journal of Mineralogy, 6, 381–385.CrossRefGoogle Scholar
O’Neill, H.S. (1987) Quartz-fayalite-iron and quartz-fayalite-magnetite equilibria and the free energy of formation of fayalite (Fe2SiO4) and magnetite (Fe3O4). American Mineralogist, 72, 67–75.Google Scholar
Patin˜o Douce, A.E. and Beard, J.S. (1994) H2O loss from hydrous melts during flfluid-absent piston cylinder experiments. American Mineralogist, 79, 585–588.Google Scholar
Robinson, J.A.C., Wood, B.J. and Blundy, J.D. (1998) The beginning of melting of fertile and depleted peridotite at 1.5 GPa. Earth and Planetary Science Letters, 155, 97–111.CrossRefGoogle Scholar
Stern, C.R. and Wyllie, P.J. (1975) Effect of iron absorption by noble metal capsules on phase boundaries in rock-melting experiments at 30 kb. American Mineralogist, 60, 681–689.Google Scholar
Takahashi, E. and Kushiro, I. (1983) Melting of a dry peridotite at high pressures and basalt magma genesis. American Mineralogist, 68, 859–879.Google Scholar
van der Laan, S.R. and Koster van Groos, A.F. (1991) PtFe alloys in experimental petrology applied to high-pressure research on Fe-bearing systems. American Mineralogist, 76, 1940–1949.Google Scholar