Umfang:
Online-Ressource
ISSN:
1617-4011
Inhalt:
Abstract/∘ C and three different oxygen fugacities fixed at the rhenium–rhenium oxide buffer (RRO), nickel–nickel oxide buffer (NNO), and iron-wüstite (IW) for oxidizing, intermediate, and reducing conditions, respectively. The water contents of minerals were measured by Raman spectroscopy that allows a very small beam size to be used and were cross-checked on a few samples with NanoSIMS analyses. f O 2 ∘ C, the storage capacity of the nominally anhydrous minerals (NAMS) increases with increasing oxygen fugacity (from the IW to the RRO buffer) from 1 wt % to 1.5 wt % H2 O in wadsleyite and from 0.1 wt % to 0.2 wt % in olivine, owing to the increase in H2 O /2 speciation in the fluid, whereas at 1400 ∘ C the storage capacity decreases from 1 wt % to 0.75 wt % H2 O in wadsleyite and down to 0.03 wt % for olivine. At high temperature, the water storage capacity is lowered due to melting, and the more oxidized the conditions are the more the solidus is depressed. Still, at 1400 ∘ C and IW, wadsleyite can store substantial amounts of water: 0.8 wt % to 1 wt % H2 O. The effect of carbon is to decrease water storage capacity in both wadsleyite and olivine by an average factor 2 at 1300–1400 ∘ C. The trends in water storage as a function of f O 2 ∘ C in the wadsleyite stability field and drops to temperatures below 1300 ∘ C in the olivine stability field. With the addition of C, the solidus is found between 1200 and 1300 ∘ C in both olivine and wadsleyite stability fields.
In:
volume:35
In:
number:4
In:
year:2023
In:
pages:549-568
In:
extent:20
In:
European journal of mineralogy, Göttingen : Copernicus Publications, 1989-, 35, Heft 4 (2023), 549-568 (gesamt 20), 1617-4011
Sprache:
Englisch
DOI:
10.5194/ejm-35-549-2023
URN:
urn:nbn:de:101:1-2023080304261807391193
URL:
https://doi.org/10.5194/ejm-35-549-2023
URL:
https://nbn-resolving.org/urn:nbn:de:101:1-2023080304261807391193
URL:
https://d-nb.info/1298109582/34
URL:
https://ejm.copernicus.org/articles/35/549/2023/ejm-35-549-2023.pdf
URL:
https://ejm.copernicus.org/articles/35/549/2023/
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