Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland
Processes in upper-crustal magma reservoirs such as recharge, magma mixing, recycling of previously crystallized material, and eruption affect both the physical state and the chemical composition of magmas. A growing body of evidence shows that crystals in intermediate or silicic volcanic rocks pres...
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ftcaltechauth:oai:authors.library.caltech.edu:n98eh-zhy78 2024-09-15T18:13:31+00:00 Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland Cooper, Kari M. Sims, Kenneth W. W. Eiler, John M. Banerjee, Neil 2016-06 https://doi.org/10.1007/s00410-016-1267-3 unknown Springer https://doi.org/10.1007/s00410-016-1267-3 oai:authors.library.caltech.edu:n98eh-zhy78 eprintid:69271 resolverid:CaltechAUTHORS:20160728-083003248 info:eu-repo/semantics/openAccess Other Contributions to Mineralogy and Petrology, 171(6), Art. No. 54, (2016-06) Iceland – Crystal mush – Uranium-series disequilibria – Oxygen isotopes – Magmatic timescales info:eu-repo/semantics/article 2016 ftcaltechauth https://doi.org/10.1007/s00410-016-1267-3 2024-08-06T15:35:05Z Processes in upper-crustal magma reservoirs such as recharge, magma mixing, recycling of previously crystallized material, and eruption affect both the physical state and the chemical composition of magmas. A growing body of evidence shows that crystals in intermediate or silicic volcanic rocks preserve records of these processes that may be obscured due to mixing in the liquid fraction of magmas. Fewer studies have focused on crystals in basaltic lavas, but these show evidence for a more subtle, but still rich record of magmatic processes. We present new ^(238)U–^(230)Th–^(226)Ra data for plagioclase, combined with δ^(18)O and trace-element measurements of the same crystal populations, from basalts erupted at Krafla Volcanic Center, Iceland. These data document the presence of multiple crystal populations within each sample, with chemical and oxygen isotope heterogeneity at a variety of scales: within individual crystals, between crystals in a given population, between crystal populations within the same sample, and between crystals in lavas erupted from different vents during the same eruption. Comparison to whole-rock or groundmass data shows that the majority of macroscopic crystals are not in trace-element or oxygen isotope equilibrium with their host liquids. The most likely explanation for these data is that the macroscopic crystals originated within a highly heterogeneous crystal mush in the shallow magma reservoir system. U-series and diffusion data indicate that the crystals (and therefore the mush) formed recently (likely within a few thousand years of eruption, and with a maximum age of 8–9 ka), and that the crystals resided in their host magma prior to eruption for decades to a few centuries at most. These data, in conjunction with other recent studies, suggest a model where erupted Icelandic magmas are the result of diverse magmas entering the crust, followed by complex interactions between melts and previously crystallized material at all crustal levels. © 2016 Springer Berlin ... Article in Journal/Newspaper Iceland Caltech Authors (California Institute of Technology) Contributions to Mineralogy and Petrology 171 6 |
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Caltech Authors (California Institute of Technology) |
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unknown |
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Iceland – Crystal mush – Uranium-series disequilibria – Oxygen isotopes – Magmatic timescales |
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Iceland – Crystal mush – Uranium-series disequilibria – Oxygen isotopes – Magmatic timescales Cooper, Kari M. Sims, Kenneth W. W. Eiler, John M. Banerjee, Neil Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
topic_facet |
Iceland – Crystal mush – Uranium-series disequilibria – Oxygen isotopes – Magmatic timescales |
description |
Processes in upper-crustal magma reservoirs such as recharge, magma mixing, recycling of previously crystallized material, and eruption affect both the physical state and the chemical composition of magmas. A growing body of evidence shows that crystals in intermediate or silicic volcanic rocks preserve records of these processes that may be obscured due to mixing in the liquid fraction of magmas. Fewer studies have focused on crystals in basaltic lavas, but these show evidence for a more subtle, but still rich record of magmatic processes. We present new ^(238)U–^(230)Th–^(226)Ra data for plagioclase, combined with δ^(18)O and trace-element measurements of the same crystal populations, from basalts erupted at Krafla Volcanic Center, Iceland. These data document the presence of multiple crystal populations within each sample, with chemical and oxygen isotope heterogeneity at a variety of scales: within individual crystals, between crystals in a given population, between crystal populations within the same sample, and between crystals in lavas erupted from different vents during the same eruption. Comparison to whole-rock or groundmass data shows that the majority of macroscopic crystals are not in trace-element or oxygen isotope equilibrium with their host liquids. The most likely explanation for these data is that the macroscopic crystals originated within a highly heterogeneous crystal mush in the shallow magma reservoir system. U-series and diffusion data indicate that the crystals (and therefore the mush) formed recently (likely within a few thousand years of eruption, and with a maximum age of 8–9 ka), and that the crystals resided in their host magma prior to eruption for decades to a few centuries at most. These data, in conjunction with other recent studies, suggest a model where erupted Icelandic magmas are the result of diverse magmas entering the crust, followed by complex interactions between melts and previously crystallized material at all crustal levels. © 2016 Springer Berlin ... |
format |
Article in Journal/Newspaper |
author |
Cooper, Kari M. Sims, Kenneth W. W. Eiler, John M. Banerjee, Neil |
author_facet |
Cooper, Kari M. Sims, Kenneth W. W. Eiler, John M. Banerjee, Neil |
author_sort |
Cooper, Kari M. |
title |
Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
title_short |
Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
title_full |
Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
title_fullStr |
Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
title_full_unstemmed |
Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
title_sort |
timescales of storage and recycling of crystal mush at krafla volcano, iceland |
publisher |
Springer |
publishDate |
2016 |
url |
https://doi.org/10.1007/s00410-016-1267-3 |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Contributions to Mineralogy and Petrology, 171(6), Art. No. 54, (2016-06) |
op_relation |
https://doi.org/10.1007/s00410-016-1267-3 oai:authors.library.caltech.edu:n98eh-zhy78 eprintid:69271 resolverid:CaltechAUTHORS:20160728-083003248 |
op_rights |
info:eu-repo/semantics/openAccess Other |
op_doi |
https://doi.org/10.1007/s00410-016-1267-3 |
container_title |
Contributions to Mineralogy and Petrology |
container_volume |
171 |
container_issue |
6 |
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1810451281954734080 |