Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation
In this study potential iron isotope fractionation by magmatic processes in the Earth's crust was systematically investigated. High precision iron isotope analyses by MC-ICP-MS were performed on a suite of rock samples representative for the volcanic evolution of the Hekla volcano, Iceland. The...
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ftgfzpotsdam:oai:gfzpublic.gfz-potsdam.de:item_238588 2023-05-15T16:34:01+02:00 Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation Schuessler, J. Schönberg, R. Sigmarsson, O. 0 Pre-GFZ, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum 2009 https://gfzpublic.gfz-potsdam.de/pubman/item/item_238588 unknown info:eu-repo/semantics/altIdentifier/doi/10.1016/j.chemgeo.2008.06.021 https://gfzpublic.gfz-potsdam.de/pubman/item/item_238588 Chemical Geology 550 - Earth sciences info:eu-repo/semantics/article 2009 ftgfzpotsdam https://doi.org/10.1016/j.chemgeo.2008.06.021 2022-09-14T05:57:02Z In this study potential iron isotope fractionation by magmatic processes in the Earth's crust was systematically investigated. High precision iron isotope analyses by MC-ICP-MS were performed on a suite of rock samples representative for the volcanic evolution of the Hekla volcano, Iceland. The whole series of Hekla's rocks results from several processes. (i) Basaltic magmas rise and induce partial melting of metabasalts in the lower part of the Icelandic crust. The resulting dacitic magma evolves to rhyolitic composition through crystal fractionation. During this differentiation the δ56/54FeIRMM-014 values increase successively from 0.051±0.021‰ for the primitive dacites to 0.168±0.021‰ for the rhyolites. This increase can be described by a Rayleigh fractionation model using a constant bulk fractionation factor between all mineral phases (M) and the silicate liquid (L) of Δ56/54FeM–L=−0.1‰. (ii) The basaltic magma itself differentiates by crystal fractionation to basaltic andesite composition. No Fe isotope fractionation was found in this series. All basalts and basaltic andesites have an average δ56/54FeIRMM-014 value of 0.062±0.042‰ (2SD, n=9), identical to mean terrestrial basaltic values reported in previous studies. This observation is consistent with the limited removal of iron from the remaining silicate melt through crystal fractionation and small mineral-melt Fe isotope fractionation factors expected at temperatures in excess of 1050 °C. (iii) Andesites are produced by mixing of basaltic andesite with dacitic melts. The iron isotope composition of the andesites is matching that of the basaltic andesites and the less evolved dacites, in agreement with a mixing process. In the Hekla volcanic suite Li concentrations are positively correlated with indicators of magma differentiation. All Hekla rocks have δ7Li values typical for the upper mantle and demonstrate the absence of resolvable Li isotope fractionation during crystal fractionation. As a fluid-mobile trace element, Li concentrations and isotopes are ... Article in Journal/Newspaper Hekla Iceland GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) Chemical Geology 258 1-2 78 91 |
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GFZpublic (German Research Centre for Geosciences, Helmholtz-Zentrum Potsdam) |
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550 - Earth sciences |
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550 - Earth sciences Schuessler, J. Schönberg, R. Sigmarsson, O. Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation |
topic_facet |
550 - Earth sciences |
description |
In this study potential iron isotope fractionation by magmatic processes in the Earth's crust was systematically investigated. High precision iron isotope analyses by MC-ICP-MS were performed on a suite of rock samples representative for the volcanic evolution of the Hekla volcano, Iceland. The whole series of Hekla's rocks results from several processes. (i) Basaltic magmas rise and induce partial melting of metabasalts in the lower part of the Icelandic crust. The resulting dacitic magma evolves to rhyolitic composition through crystal fractionation. During this differentiation the δ56/54FeIRMM-014 values increase successively from 0.051±0.021‰ for the primitive dacites to 0.168±0.021‰ for the rhyolites. This increase can be described by a Rayleigh fractionation model using a constant bulk fractionation factor between all mineral phases (M) and the silicate liquid (L) of Δ56/54FeM–L=−0.1‰. (ii) The basaltic magma itself differentiates by crystal fractionation to basaltic andesite composition. No Fe isotope fractionation was found in this series. All basalts and basaltic andesites have an average δ56/54FeIRMM-014 value of 0.062±0.042‰ (2SD, n=9), identical to mean terrestrial basaltic values reported in previous studies. This observation is consistent with the limited removal of iron from the remaining silicate melt through crystal fractionation and small mineral-melt Fe isotope fractionation factors expected at temperatures in excess of 1050 °C. (iii) Andesites are produced by mixing of basaltic andesite with dacitic melts. The iron isotope composition of the andesites is matching that of the basaltic andesites and the less evolved dacites, in agreement with a mixing process. In the Hekla volcanic suite Li concentrations are positively correlated with indicators of magma differentiation. All Hekla rocks have δ7Li values typical for the upper mantle and demonstrate the absence of resolvable Li isotope fractionation during crystal fractionation. As a fluid-mobile trace element, Li concentrations and isotopes are ... |
author2 |
0 Pre-GFZ, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum |
format |
Article in Journal/Newspaper |
author |
Schuessler, J. Schönberg, R. Sigmarsson, O. |
author_facet |
Schuessler, J. Schönberg, R. Sigmarsson, O. |
author_sort |
Schuessler, J. |
title |
Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation |
title_short |
Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation |
title_full |
Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation |
title_fullStr |
Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation |
title_full_unstemmed |
Iron and lithium isotope systematics of the Hekla volcano, Iceland - Evidence for Fe isotope fractionation during magma differentiation |
title_sort |
iron and lithium isotope systematics of the hekla volcano, iceland - evidence for fe isotope fractionation during magma differentiation |
publishDate |
2009 |
url |
https://gfzpublic.gfz-potsdam.de/pubman/item/item_238588 |
genre |
Hekla Iceland |
genre_facet |
Hekla Iceland |
op_source |
Chemical Geology |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.chemgeo.2008.06.021 https://gfzpublic.gfz-potsdam.de/pubman/item/item_238588 |
op_doi |
https://doi.org/10.1016/j.chemgeo.2008.06.021 |
container_title |
Chemical Geology |
container_volume |
258 |
container_issue |
1-2 |
container_start_page |
78 |
op_container_end_page |
91 |
_version_ |
1766023773672177664 |