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Zircon as a recorder of the oxygen fugacity of magmas
2012Zircon (ZrSiO4) is a durable mineral found in most igneous rocks; it is highly retentive of the trace element concentrations it acquires at crystallisation, and its high initial concentrations of U and Th relative to Pb make it the most important mineral for radiometric dating.
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Kaersutitic and Ti-pargasitic amphiboles and oxygen fugacity
2008Since long time kaersutite and Ti-pargasite were studied because they are retained to be useful for the estimation of fO2 and fH2 conditions of their hosting rocks (especially for mantle derived rocks and nodules). These amphiboles have currently low hydrogen (even close to 0) content than the classical 2 a.p.f.u..
Iezzi G +3 more
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Oxygen fugacity controls in the Earth's upper mantle
Nature, 1990DESPITE significant progress in recent years1–3, there is still considerable debate surrounding the oxygen fugacity (fo2) of the Earth's upper mantle and the chemical reactions that buffer it. Electrochemical measurements1,3 give heterogeneous oxidation states, with one group near the fayalite–magnetite–quartz (FMQ), and the other near the iron-wustite
C. Ballhaus, R. F. Berry, D. H. Green
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Equilibrium oxygen fugacity in zinc-titanium ferrites of ideal oxygen stoichiometry
Materials Research Bulletin, 1988Abstract A thermodynamic analysis is provided to specify the oxygen equilibrium pressures in the system Znx Tiy Fe3−x−yO4 for the special case of the ideal oxygen stoichiometry O ( Zn + Ti + Fe ) , 4 3 . The principal features of the results are briefly discussed.
P. Wang, J.M. Honig
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Records of Archean mantle oxygen fugacity
Goldschmidt2023 abstracts, 2023Elizabeth Cottrell +5 more
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The effect of hydrogen, oxygen, and water fugacity on oxygen diffusion in alkali feldspar
Geochimica et Cosmochimica Acta, 1990Abstract Oxygen self-diffusion in adularia and albite single crystals was studied hydrothermally at 650°C from 5 to 1500 MPa confining pressure using a combination of hydrogen/oxygen buffers, a hydrogen ion buffer, and variable mole fractions of water (dilution with CO2).
John R. Farver, Richard A. Yund
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The oxidation state of europium as an indicator of oxygen fugacity
Geochimica et Cosmochimica Acta, 1975Empirical oxygen barometers based on Eu(2+)/Eu(3+) ratios in plagioclase feldspar and magmatic liquid were developed using Philpott's (1970) approach and the experimental data of Drake (1972). Oxygen fugacities calculated on the basis of Eu(2+)/Eu(3+) ratios for terrestrial basalts cluster tightly around 10 to the negative seventh power.
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Journal of Geophysical Research, 1973
Water fugacity and oxygen fugacity can be controlled concomitantly in solid-media high-pressure apparatus by using CO2-H2O vapors and the double-capsule technique with oxygen buffers. Calculations based on an ideal-solution model yield values of the fugacities of O2, H2, and H2O in the samples.
A. L. Boettcher +2 more
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Water fugacity and oxygen fugacity can be controlled concomitantly in solid-media high-pressure apparatus by using CO2-H2O vapors and the double-capsule technique with oxygen buffers. Calculations based on an ideal-solution model yield values of the fugacities of O2, H2, and H2O in the samples.
A. L. Boettcher +2 more
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Oxygen buffering of Kilauea volcanic gases and the oxygen fugacity of Kilauea basalt
Geochimica et Cosmochimica Acta, 1993Volcanic gases collected during episode 1 of the Puu Oo eruption along the east rift zone of Kilauea Volcano, Hawaii, have uniform C-O-H-S-Cl-F compositions that are sharply depleted in CO2. The CO2-poor gases are typical of Type II volcanic gases (gerlach and Graeber, 1985) and were emitted from evolved magma stored for a prolonged period of time in ...
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The effects of oxygen fugacity on mineral stabilities in kimberlite
Goldschmidt2022 abstracts, 2022Zairong Liu +3 more
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