Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach.
Magma generation in the Ross Sea system is related to partial melting of strongly metasomatized mantle sources where amphibole most probably plays a crucial role. In this context, metasomatism induced by a mela-nephelinite melt in lithospheric mantle of the Mt. Melbourne Volcanic Province (northern...
Published in: | Geological Society, London, Special Publications |
---|---|
Main Authors: | , , , , , , |
Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2008
|
Subjects: | |
Online Access: | http://hdl.handle.net/11392/524047 https://doi.org/10.1144/SP293.13 http://usr_valut |
id |
ftunivferrarair:oai:iris.unife.it:11392/524047 |
---|---|
record_format |
openpolar |
spelling |
ftunivferrarair:oai:iris.unife.it:11392/524047 2024-02-11T09:58:33+01:00 Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. Perinelli C. Orlando A. Conte A. M. Armienti P. Borrini D. Misiti V. FACCINI, Barbara Perinelli, C. Orlando, A. Conte, A. M. Armienti, P. Borrini, D. Faccini, Barbara Misiti, V. 2008 STAMPA http://hdl.handle.net/11392/524047 https://doi.org/10.1144/SP293.13 http://usr_valut eng eng volume:293 firstpage:279 lastpage:302 journal:JOURNAL OF THE GEOLOGICAL SOCIETY http://hdl.handle.net/11392/524047 doi:10.1144/SP293.13 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-38349096417 http://usr_valut info:eu-repo/semantics/article 2008 ftunivferrarair https://doi.org/10.1144/SP293.13 2024-01-24T17:36:54Z Magma generation in the Ross Sea system is related to partial melting of strongly metasomatized mantle sources where amphibole most probably plays a crucial role. In this context, metasomatism induced by a mela-nephelinite melt in lithospheric mantle of the Mt. Melbourne Volcanic Province (northern Victoria Land (NVL), Antarctica) was investigated experimentally studying the effects of melt interaction with lherzolite at 1.5–2.0 GPa and T ¼ 975–1300 8C, and wehrlite at 1.0 GPa and T ¼ 1050–1250 8C. The experiments were designed to induce melt infiltration into the ultramafic rocks. The observed modifications in minerals are compared with those found in mantle xenoliths from NVL. The effects of metasomatic modifications are evaluated on the basis of run temperature, distance from the infiltrating melt and the diffusion rates of chemical components. Both in lherzolite and wehrlite, clinopyroxene exhibits large compositional variations ranging from primary diopside to high-Mg–Cr–(Na) augitic and omphacitic clinopyroxenes in lherzolite, and to low-Mg and high-Ti–Al–Fe–Na augites in wehrlite. Olivine (in wehrlite) and spinel (in lherzolite) are also compositionally modified: the former shows enrichment in Fe and the latter displays a higher Cr/(Cr þ Al) ratio. The systematic variations in mineral compositions imply modifications of the chemistry of the infiltrating melt as recorded by the glass veinlets and patches observed in some charges. In experiments involving wehrlite paragenesis, the glass composition approaches that of melt patches associated with both amphibole-free and amphibole-bearing natural samples, and is related to olivine þ clinopyroxene crystallization coupled with primary clinopyroxene dissolution at the contact between the metasomatizing melt and the solid matrix. Even if amphibole crystallization was not attained in the experiments, we were able to explain the occurrence of amphibole in the natural system considering that in this case a hot metasomatizing melt infiltrates a cooler matrix. Article in Journal/Newspaper Antarc* Antarctica antartic* Ross Sea Victoria Land Università degli Studi di Ferrara: CINECA IRIS Ross Sea Victoria Land Geological Society, London, Special Publications 293 1 279 302 |
institution |
Open Polar |
collection |
Università degli Studi di Ferrara: CINECA IRIS |
op_collection_id |
ftunivferrarair |
language |
English |
description |
Magma generation in the Ross Sea system is related to partial melting of strongly metasomatized mantle sources where amphibole most probably plays a crucial role. In this context, metasomatism induced by a mela-nephelinite melt in lithospheric mantle of the Mt. Melbourne Volcanic Province (northern Victoria Land (NVL), Antarctica) was investigated experimentally studying the effects of melt interaction with lherzolite at 1.5–2.0 GPa and T ¼ 975–1300 8C, and wehrlite at 1.0 GPa and T ¼ 1050–1250 8C. The experiments were designed to induce melt infiltration into the ultramafic rocks. The observed modifications in minerals are compared with those found in mantle xenoliths from NVL. The effects of metasomatic modifications are evaluated on the basis of run temperature, distance from the infiltrating melt and the diffusion rates of chemical components. Both in lherzolite and wehrlite, clinopyroxene exhibits large compositional variations ranging from primary diopside to high-Mg–Cr–(Na) augitic and omphacitic clinopyroxenes in lherzolite, and to low-Mg and high-Ti–Al–Fe–Na augites in wehrlite. Olivine (in wehrlite) and spinel (in lherzolite) are also compositionally modified: the former shows enrichment in Fe and the latter displays a higher Cr/(Cr þ Al) ratio. The systematic variations in mineral compositions imply modifications of the chemistry of the infiltrating melt as recorded by the glass veinlets and patches observed in some charges. In experiments involving wehrlite paragenesis, the glass composition approaches that of melt patches associated with both amphibole-free and amphibole-bearing natural samples, and is related to olivine þ clinopyroxene crystallization coupled with primary clinopyroxene dissolution at the contact between the metasomatizing melt and the solid matrix. Even if amphibole crystallization was not attained in the experiments, we were able to explain the occurrence of amphibole in the natural system considering that in this case a hot metasomatizing melt infiltrates a cooler matrix. |
author2 |
Perinelli, C. Orlando, A. Conte, A. M. Armienti, P. Borrini, D. Faccini, Barbara Misiti, V. |
format |
Article in Journal/Newspaper |
author |
Perinelli C. Orlando A. Conte A. M. Armienti P. Borrini D. Misiti V. FACCINI, Barbara |
spellingShingle |
Perinelli C. Orlando A. Conte A. M. Armienti P. Borrini D. Misiti V. FACCINI, Barbara Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. |
author_facet |
Perinelli C. Orlando A. Conte A. M. Armienti P. Borrini D. Misiti V. FACCINI, Barbara |
author_sort |
Perinelli C. |
title |
Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. |
title_short |
Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. |
title_full |
Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. |
title_fullStr |
Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. |
title_full_unstemmed |
Metasomatism induced by alkaline magma in the upper mantle of Northern Victoria Land (Antartica): an experimental approach. |
title_sort |
metasomatism induced by alkaline magma in the upper mantle of northern victoria land (antartica): an experimental approach. |
publishDate |
2008 |
url |
http://hdl.handle.net/11392/524047 https://doi.org/10.1144/SP293.13 http://usr_valut |
geographic |
Ross Sea Victoria Land |
geographic_facet |
Ross Sea Victoria Land |
genre |
Antarc* Antarctica antartic* Ross Sea Victoria Land |
genre_facet |
Antarc* Antarctica antartic* Ross Sea Victoria Land |
op_relation |
volume:293 firstpage:279 lastpage:302 journal:JOURNAL OF THE GEOLOGICAL SOCIETY http://hdl.handle.net/11392/524047 doi:10.1144/SP293.13 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-38349096417 http://usr_valut |
op_doi |
https://doi.org/10.1144/SP293.13 |
container_title |
Geological Society, London, Special Publications |
container_volume |
293 |
container_issue |
1 |
container_start_page |
279 |
op_container_end_page |
302 |
_version_ |
1790594243678437376 |