Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano
Here we present a confocal Fe K-edge μ-XANES method (where XANES stands for X-ray absorption near-edge spectroscopy) for the analysis of Fe oxidation state in heterogeneous and one-side-polished samples. The new technique allows for an analysis of small volumes with high spatial 3D resolution of <...
Published in: | European Journal of Mineralogy |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Copernicus Publications (EGU)
2024
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Online Access: | https://oceanrep.geomar.de/id/eprint/59955/ https://oceanrep.geomar.de/id/eprint/59955/1/ejm-36-195-2024.pdf https://oceanrep.geomar.de/id/eprint/59955/2/2024_Botscharnikov%20et%20al.%20-%20Euer.%20J%20Miner%20-%20Supplement.zip https://doi.org/10.5194/ejm-36-195-2024 |
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ftoceanrep:oai:oceanrep.geomar.de:59955 2024-04-28T08:23:07+00:00 Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano Botcharnikov, Roman Wilke, Max Garrevoet, Jan Portnyagin, Maxim Klimm, Kevin Buhre, Stephan Krasheninnikov, Stepan Almeev, Renat Moune, Severine Falkenberg, Gerald 2024-02-12 text archive https://oceanrep.geomar.de/id/eprint/59955/ https://oceanrep.geomar.de/id/eprint/59955/1/ejm-36-195-2024.pdf https://oceanrep.geomar.de/id/eprint/59955/2/2024_Botscharnikov%20et%20al.%20-%20Euer.%20J%20Miner%20-%20Supplement.zip https://doi.org/10.5194/ejm-36-195-2024 en eng Copernicus Publications (EGU) https://oceanrep.geomar.de/id/eprint/59955/1/ejm-36-195-2024.pdf https://oceanrep.geomar.de/id/eprint/59955/2/2024_Botscharnikov%20et%20al.%20-%20Euer.%20J%20Miner%20-%20Supplement.zip Botcharnikov, R., Wilke, M., Garrevoet, J., Portnyagin, M. , Klimm, K., Buhre, S., Krasheninnikov, S., Almeev, R., Moune, S. and Falkenberg, G. (2024) Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano. Open Access European Journal of Mineralogy, 36 (1). pp. 195-208. DOI 10.5194/ejm-36-195-2024 <https://doi.org/10.5194/ejm-36-195-2024>. doi:10.5194/ejm-36-195-2024 cc_by_4.0 info:eu-repo/semantics/openAccess Article PeerReviewed 2024 ftoceanrep https://doi.org/10.5194/ejm-36-195-2024 2024-04-10T00:05:17Z Here we present a confocal Fe K-edge μ-XANES method (where XANES stands for X-ray absorption near-edge spectroscopy) for the analysis of Fe oxidation state in heterogeneous and one-side-polished samples. The new technique allows for an analysis of small volumes with high spatial 3D resolution of <100 µm3. The probed volume is restricted to that just beneath the surface of the exposed object. This protocol avoids contamination of the signal by the host material and minimizes self-absorption effects. This technique has been tested on a set of experimental glasses with a wide range of Fe3+ ΣFe ratios. The method was applied to the analysis of natural melt inclusions trapped in forsteritic to fayalitic olivine crystals of the Hekla volcano, Iceland. Our measurements reveal changes in Fe3+ ΣFe from 0.17 in basaltic up to 0.45 in dacitic melts, whereas the magnetite–ilmenite equilibrium shows redox conditions with Fe3+ ΣFe ≤0.20 (close to FMQ, fayalite–magnetite–quartz redox equilibrium) along the entire range of Hekla melt compositions. This discrepancy indicates that the oxidized nature of glasses in the melt inclusions could be related to the post-entrapment process of diffusive hydrogen loss from inclusions and associated oxidation of Fe in the melt. The Fe3+ ΣFe ratio in silicic melts is particularly susceptible to this process due to their low FeO content, and it should be critically evaluated before petrological interpretation. Article in Journal/Newspaper Hekla Iceland OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) European Journal of Mineralogy 36 1 195 208 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Here we present a confocal Fe K-edge μ-XANES method (where XANES stands for X-ray absorption near-edge spectroscopy) for the analysis of Fe oxidation state in heterogeneous and one-side-polished samples. The new technique allows for an analysis of small volumes with high spatial 3D resolution of <100 µm3. The probed volume is restricted to that just beneath the surface of the exposed object. This protocol avoids contamination of the signal by the host material and minimizes self-absorption effects. This technique has been tested on a set of experimental glasses with a wide range of Fe3+ ΣFe ratios. The method was applied to the analysis of natural melt inclusions trapped in forsteritic to fayalitic olivine crystals of the Hekla volcano, Iceland. Our measurements reveal changes in Fe3+ ΣFe from 0.17 in basaltic up to 0.45 in dacitic melts, whereas the magnetite–ilmenite equilibrium shows redox conditions with Fe3+ ΣFe ≤0.20 (close to FMQ, fayalite–magnetite–quartz redox equilibrium) along the entire range of Hekla melt compositions. This discrepancy indicates that the oxidized nature of glasses in the melt inclusions could be related to the post-entrapment process of diffusive hydrogen loss from inclusions and associated oxidation of Fe in the melt. The Fe3+ ΣFe ratio in silicic melts is particularly susceptible to this process due to their low FeO content, and it should be critically evaluated before petrological interpretation. |
format |
Article in Journal/Newspaper |
author |
Botcharnikov, Roman Wilke, Max Garrevoet, Jan Portnyagin, Maxim Klimm, Kevin Buhre, Stephan Krasheninnikov, Stepan Almeev, Renat Moune, Severine Falkenberg, Gerald |
spellingShingle |
Botcharnikov, Roman Wilke, Max Garrevoet, Jan Portnyagin, Maxim Klimm, Kevin Buhre, Stephan Krasheninnikov, Stepan Almeev, Renat Moune, Severine Falkenberg, Gerald Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano |
author_facet |
Botcharnikov, Roman Wilke, Max Garrevoet, Jan Portnyagin, Maxim Klimm, Kevin Buhre, Stephan Krasheninnikov, Stepan Almeev, Renat Moune, Severine Falkenberg, Gerald |
author_sort |
Botcharnikov, Roman |
title |
Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano |
title_short |
Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano |
title_full |
Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano |
title_fullStr |
Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano |
title_full_unstemmed |
Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano |
title_sort |
confocal μ -xanes as a tool to analyze fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the hekla volcano |
publisher |
Copernicus Publications (EGU) |
publishDate |
2024 |
url |
https://oceanrep.geomar.de/id/eprint/59955/ https://oceanrep.geomar.de/id/eprint/59955/1/ejm-36-195-2024.pdf https://oceanrep.geomar.de/id/eprint/59955/2/2024_Botscharnikov%20et%20al.%20-%20Euer.%20J%20Miner%20-%20Supplement.zip https://doi.org/10.5194/ejm-36-195-2024 |
genre |
Hekla Iceland |
genre_facet |
Hekla Iceland |
op_relation |
https://oceanrep.geomar.de/id/eprint/59955/1/ejm-36-195-2024.pdf https://oceanrep.geomar.de/id/eprint/59955/2/2024_Botscharnikov%20et%20al.%20-%20Euer.%20J%20Miner%20-%20Supplement.zip Botcharnikov, R., Wilke, M., Garrevoet, J., Portnyagin, M. , Klimm, K., Buhre, S., Krasheninnikov, S., Almeev, R., Moune, S. and Falkenberg, G. (2024) Confocal μ -XANES as a tool to analyze Fe oxidation state in heterogeneous samples: the case of melt inclusions in olivine from the Hekla volcano. Open Access European Journal of Mineralogy, 36 (1). pp. 195-208. DOI 10.5194/ejm-36-195-2024 <https://doi.org/10.5194/ejm-36-195-2024>. doi:10.5194/ejm-36-195-2024 |
op_rights |
cc_by_4.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/ejm-36-195-2024 |
container_title |
European Journal of Mineralogy |
container_volume |
36 |
container_issue |
1 |
container_start_page |
195 |
op_container_end_page |
208 |
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1797584289983889408 |