Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Hall, L. J. Articles by Carroll, M. R. Search for Related Content GeoRef GeoRef Citation

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

Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK

^* E-mail: b.j.wood{at}bris.ac.uk

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 f_O2 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 f_O2 unit below the QFM buffer at 1atm lost, on average, 32% of their H₂O when run in Au₈₀Pd₂₀O₂ 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 loss, water, hydrous basalt, AuPd capsules

This article has been cited by other articles:

				R. E. Botcharnikov, R. R. Almeev, J. Koepke, and F. Holtz Phase Relations and Liquid Lines of Descent in Hydrous Ferrobasalt--Implications for the Skaergaard Intrusion and Columbia River Flood Basalts J. Petrology, September 1, 2008; 49(9): 1687 - 1727. [Abstract] [Full Text] [PDF]