The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash)
Major, trace and volatile elements were measured in a suite of primitive macrocrysts and melt inclusions from the thickest layer of the 10 ka Grímsvötn tephra series (i.e. Saksunarvatn ash) at Lake Hvítárvatn in central Iceland. In the absence of primitive tholeiitic eruptions (MgO > 7 wt%) withi...
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Berlin : Springer Verlag
2015
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ftunivhannover:oai:www.repo.uni-hannover.de:123456789/884 2023-07-16T03:59:06+02:00 The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) Neave, David A. Maclennan, John Thordarson, Thorvaldur Hartley, Margaret E. 2015 http://www.repo.uni-hannover.de/handle/123456789/884 https://doi.org/10.15488/860 eng eng Berlin : Springer Verlag DOI:https://doi.org/10.1007/s00410-015-1170-3 ISSN:00107999 http://dx.doi.org/10.15488/860 http://www.repo.uni-hannover.de/handle/123456789/884 CC BY 4.0 Unported https://creativecommons.org/licenses/by/4.0/ frei zugänglich Contributions to Mineralogy and Petrology 170 (2015), Nr. 2 Basalt Iceland Plagioclase-hosted melt inclusions Saksunarvatn Thermobarometry barometry enrichment host rock igneous geochemistry melt inclusion phase equilibrium plagioclase pressure effect tephra trace element volcanic eruption Grimsvotn Hvitarvatn ddc:550 status-type:publishedVersion doc-type:Article doc-type:Text 2015 ftunivhannover https://doi.org/10.15488/86010.1007/s00410-015-1170-3 2023-06-28T10:36:04Z Major, trace and volatile elements were measured in a suite of primitive macrocrysts and melt inclusions from the thickest layer of the 10 ka Grímsvötn tephra series (i.e. Saksunarvatn ash) at Lake Hvítárvatn in central Iceland. In the absence of primitive tholeiitic eruptions (MgO > 7 wt%) within the Eastern Volcanic Zone (EVZ) of Iceland, these crystal and inclusion compositions provide an important insight into magmatic processes in this volcanically productive region. Matrix glass compositions show strong similarities with glass compositions from the AD 1783–1784 Laki eruption, confirming the affinity of the tephra series with the Grímsvötn volcanic system. Macrocrysts can be divided into a primitive assemblage of zoned macrocryst cores (An78–An92, Mg#cpx = 82–87, Fo79.5–Fo87) and an evolved assemblage consisting of unzoned macrocrysts and the rims of zoned macrocrysts (An60–An68, Mg#cpx = 71–78, Fo70–Fo76). Although the evolved assemblage is close to being in equilibrium with the matrix glass, trace element disequilibrium between primitive and evolved assemblages indicates that they were derived from different distributions of mantle melt compositions. Juxtaposition of disequilibrium assemblages probably occurred during disaggregation of incompatible trace element-depleted mushes (mean La/Ybmelt = 2.1) into aphyric and incompatible trace element-enriched liquids (La/Ybmelt = 3.6) shortly before the growth of the evolved macrocryst assemblage. Post-entrapment modification of plagioclase-hosted melt inclusions has been minimal and high-Mg# inclusions record differentiation and mixing of compositionally variable mantle melts that are amongst the most primitive liquids known from the EVZ. Coupled high-field strength element (HFSE) depletion and incompatible trace element enrichment in a subset of primitive plagioclase-hosted melt inclusions can be accounted for by inclusion formation following plagioclase dissolution driven by interaction with plagioclase-undersaturated melts. Thermobarometric calculations ... Article in Journal/Newspaper Iceland Institutional Repository of Leibniz Universität Hannover Grimsvotn ENVELOPE(-17.319,-17.319,64.416,64.416) Hvítárvatn ENVELOPE(-19.837,-19.837,64.612,64.612) Laki ENVELOPE(-18.237,-18.237,64.070,64.070) Saksunarvatn ENVELOPE(-7.150,-7.150,62.233,62.233) |
institution |
Open Polar |
collection |
Institutional Repository of Leibniz Universität Hannover |
op_collection_id |
ftunivhannover |
language |
English |
topic |
Basalt Iceland Plagioclase-hosted melt inclusions Saksunarvatn Thermobarometry barometry enrichment host rock igneous geochemistry melt inclusion phase equilibrium plagioclase pressure effect tephra trace element volcanic eruption Grimsvotn Hvitarvatn ddc:550 |
spellingShingle |
Basalt Iceland Plagioclase-hosted melt inclusions Saksunarvatn Thermobarometry barometry enrichment host rock igneous geochemistry melt inclusion phase equilibrium plagioclase pressure effect tephra trace element volcanic eruption Grimsvotn Hvitarvatn ddc:550 Neave, David A. Maclennan, John Thordarson, Thorvaldur Hartley, Margaret E. The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) |
topic_facet |
Basalt Iceland Plagioclase-hosted melt inclusions Saksunarvatn Thermobarometry barometry enrichment host rock igneous geochemistry melt inclusion phase equilibrium plagioclase pressure effect tephra trace element volcanic eruption Grimsvotn Hvitarvatn ddc:550 |
description |
Major, trace and volatile elements were measured in a suite of primitive macrocrysts and melt inclusions from the thickest layer of the 10 ka Grímsvötn tephra series (i.e. Saksunarvatn ash) at Lake Hvítárvatn in central Iceland. In the absence of primitive tholeiitic eruptions (MgO > 7 wt%) within the Eastern Volcanic Zone (EVZ) of Iceland, these crystal and inclusion compositions provide an important insight into magmatic processes in this volcanically productive region. Matrix glass compositions show strong similarities with glass compositions from the AD 1783–1784 Laki eruption, confirming the affinity of the tephra series with the Grímsvötn volcanic system. Macrocrysts can be divided into a primitive assemblage of zoned macrocryst cores (An78–An92, Mg#cpx = 82–87, Fo79.5–Fo87) and an evolved assemblage consisting of unzoned macrocrysts and the rims of zoned macrocrysts (An60–An68, Mg#cpx = 71–78, Fo70–Fo76). Although the evolved assemblage is close to being in equilibrium with the matrix glass, trace element disequilibrium between primitive and evolved assemblages indicates that they were derived from different distributions of mantle melt compositions. Juxtaposition of disequilibrium assemblages probably occurred during disaggregation of incompatible trace element-depleted mushes (mean La/Ybmelt = 2.1) into aphyric and incompatible trace element-enriched liquids (La/Ybmelt = 3.6) shortly before the growth of the evolved macrocryst assemblage. Post-entrapment modification of plagioclase-hosted melt inclusions has been minimal and high-Mg# inclusions record differentiation and mixing of compositionally variable mantle melts that are amongst the most primitive liquids known from the EVZ. Coupled high-field strength element (HFSE) depletion and incompatible trace element enrichment in a subset of primitive plagioclase-hosted melt inclusions can be accounted for by inclusion formation following plagioclase dissolution driven by interaction with plagioclase-undersaturated melts. Thermobarometric calculations ... |
format |
Article in Journal/Newspaper |
author |
Neave, David A. Maclennan, John Thordarson, Thorvaldur Hartley, Margaret E. |
author_facet |
Neave, David A. Maclennan, John Thordarson, Thorvaldur Hartley, Margaret E. |
author_sort |
Neave, David A. |
title |
The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) |
title_short |
The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) |
title_full |
The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) |
title_fullStr |
The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) |
title_full_unstemmed |
The evolution and storage of primitive melts in the Eastern Volcanic Zone of Iceland: the 10 ka Grímsvötn tephra series (i.e. the Saksunarvatn ash) |
title_sort |
evolution and storage of primitive melts in the eastern volcanic zone of iceland: the 10 ka grímsvötn tephra series (i.e. the saksunarvatn ash) |
publisher |
Berlin : Springer Verlag |
publishDate |
2015 |
url |
http://www.repo.uni-hannover.de/handle/123456789/884 https://doi.org/10.15488/860 |
long_lat |
ENVELOPE(-17.319,-17.319,64.416,64.416) ENVELOPE(-19.837,-19.837,64.612,64.612) ENVELOPE(-18.237,-18.237,64.070,64.070) ENVELOPE(-7.150,-7.150,62.233,62.233) |
geographic |
Grimsvotn Hvítárvatn Laki Saksunarvatn |
geographic_facet |
Grimsvotn Hvítárvatn Laki Saksunarvatn |
genre |
Iceland |
genre_facet |
Iceland |
op_source |
Contributions to Mineralogy and Petrology 170 (2015), Nr. 2 |
op_relation |
DOI:https://doi.org/10.1007/s00410-015-1170-3 ISSN:00107999 http://dx.doi.org/10.15488/860 http://www.repo.uni-hannover.de/handle/123456789/884 |
op_rights |
CC BY 4.0 Unported https://creativecommons.org/licenses/by/4.0/ frei zugänglich |
op_doi |
https://doi.org/10.15488/86010.1007/s00410-015-1170-3 |
_version_ |
1771546610849808384 |