Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland
© 2016, Springer-Verlag Berlin Heidelberg. 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...
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ftcdlib:qt3pv2h3pk 2023-05-15T16:49:13+02:00 Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland Cooper, KM Sims, KWW Eiler, JM Banerjee, N 2016-06-01 application/pdf http://www.escholarship.org/uc/item/3pv2h3pk english eng eScholarship, University of California qt3pv2h3pk http://www.escholarship.org/uc/item/3pv2h3pk public Cooper, KM; Sims, KWW; Eiler, JM; & Banerjee, N. (2016). Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland. Contributions to Mineralogy and Petrology, 171(6). doi:10.1007/s00410-016-1267-3. UC Davis: Retrieved from: http://www.escholarship.org/uc/item/3pv2h3pk article 2016 ftcdlib https://doi.org/10.1007/s00410-016-1267-3 2018-06-29T22:51:47Z © 2016, Springer-Verlag Berlin Heidelberg. 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 new238U–230Th–226Ra data for plagioclase, combined with δ18O 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. Article in Journal/Newspaper Iceland University of California: eScholarship Krafla ENVELOPE(-16.747,-16.747,65.713,65.713) Contributions to Mineralogy and Petrology 171 6 |
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Open Polar |
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University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
description |
© 2016, Springer-Verlag Berlin Heidelberg. 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 new238U–230Th–226Ra data for plagioclase, combined with δ18O 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. |
format |
Article in Journal/Newspaper |
author |
Cooper, KM Sims, KWW Eiler, JM Banerjee, N |
spellingShingle |
Cooper, KM Sims, KWW Eiler, JM Banerjee, N Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland |
author_facet |
Cooper, KM Sims, KWW Eiler, JM Banerjee, N |
author_sort |
Cooper, KM |
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 |
eScholarship, University of California |
publishDate |
2016 |
url |
http://www.escholarship.org/uc/item/3pv2h3pk |
long_lat |
ENVELOPE(-16.747,-16.747,65.713,65.713) |
geographic |
Krafla |
geographic_facet |
Krafla |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Cooper, KM; Sims, KWW; Eiler, JM; & Banerjee, N. (2016). Timescales of storage and recycling of crystal mush at Krafla Volcano, Iceland. Contributions to Mineralogy and Petrology, 171(6). doi:10.1007/s00410-016-1267-3. UC Davis: Retrieved from: http://www.escholarship.org/uc/item/3pv2h3pk |
op_relation |
qt3pv2h3pk http://www.escholarship.org/uc/item/3pv2h3pk |
op_rights |
public |
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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1766039374596669440 |