The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica
Middle Jurassic continental flood basalts of Vestfjella, western Dronning Maud Land are cut by gabbroic intrusions that represent rare exposures of Karoo-related mafic plutons in Antarctica. The gabbros and numerous associated dolerites indicate high magmatic activity along the continental margin of...
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Online Access: | http://dx.doi.org/10.1017/s0954102003001287 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102003001287 |
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crcambridgeupr:10.1017/s0954102003001287 2024-03-03T08:38:49+00:00 The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica VUORI, SAKU K. V. LUTTINEN, ARTO 2003 http://dx.doi.org/10.1017/s0954102003001287 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102003001287 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Antarctic Science volume 15, issue 2, page 283-301 ISSN 0954-1020 1365-2079 Geology Ecology, Evolution, Behavior and Systematics Oceanography journal-article 2003 crcambridgeupr https://doi.org/10.1017/s0954102003001287 2024-02-08T08:37:43Z Middle Jurassic continental flood basalts of Vestfjella, western Dronning Maud Land are cut by gabbroic intrusions that represent rare exposures of Karoo-related mafic plutons in Antarctica. The gabbros and numerous associated dolerites indicate high magmatic activity along the continental margin of Dronning Maud Land during the break-up of Gondwana. The scattered nunataks of Utpostane (∼25 km 2 ) are dominated by olivine gabbronorite and olivine mela-gabbronorite, which can be grouped into four zones. The Utpostane intrusion exhibits inclined sheet-like geometry, is at least ∼3 km thick and shows moderate enrichment of incompatible element contents from its base towards the exposed roof contact (e.g. Zr from ∼15 to ∼60 ppm). High MgO contents (∼8–36 wt%) indicate that the parental magma of Utpostane was more primitive than a typical Karoo tholeiite (MgO ∼6 wt%). At Muren, gabbroic outcrops record a cross section of a ∼1.3 km thick inclined sheet-like intrusion. The intrusion can be divided to two main units, the upper and lower zones, which are dominated by olivine gabbro and gabbronorite, respectively. Parental melts of the geochemically differentiated upper zone and the homogeneous lower zone of Muren were typical low-MgO Karoo tholeiites, but they were chemically distinct and were emplaced as separate magma pulses. Article in Journal/Newspaper Antarc* Antarctic Science Antarctica Dronning Maud Land Cambridge University Press Dronning Maud Land Vestfjella ENVELOPE(-14.000,-14.000,-73.167,-73.167) Utpostane ENVELOPE(-15.667,-15.667,-73.917,-73.917) Muren ENVELOPE(-15.000,-15.000,-73.733,-73.733) Antarctic Science 15 2 283 301 |
institution |
Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
topic |
Geology Ecology, Evolution, Behavior and Systematics Oceanography |
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Geology Ecology, Evolution, Behavior and Systematics Oceanography VUORI, SAKU K. V. LUTTINEN, ARTO The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica |
topic_facet |
Geology Ecology, Evolution, Behavior and Systematics Oceanography |
description |
Middle Jurassic continental flood basalts of Vestfjella, western Dronning Maud Land are cut by gabbroic intrusions that represent rare exposures of Karoo-related mafic plutons in Antarctica. The gabbros and numerous associated dolerites indicate high magmatic activity along the continental margin of Dronning Maud Land during the break-up of Gondwana. The scattered nunataks of Utpostane (∼25 km 2 ) are dominated by olivine gabbronorite and olivine mela-gabbronorite, which can be grouped into four zones. The Utpostane intrusion exhibits inclined sheet-like geometry, is at least ∼3 km thick and shows moderate enrichment of incompatible element contents from its base towards the exposed roof contact (e.g. Zr from ∼15 to ∼60 ppm). High MgO contents (∼8–36 wt%) indicate that the parental magma of Utpostane was more primitive than a typical Karoo tholeiite (MgO ∼6 wt%). At Muren, gabbroic outcrops record a cross section of a ∼1.3 km thick inclined sheet-like intrusion. The intrusion can be divided to two main units, the upper and lower zones, which are dominated by olivine gabbro and gabbronorite, respectively. Parental melts of the geochemically differentiated upper zone and the homogeneous lower zone of Muren were typical low-MgO Karoo tholeiites, but they were chemically distinct and were emplaced as separate magma pulses. |
format |
Article in Journal/Newspaper |
author |
VUORI, SAKU K. V. LUTTINEN, ARTO |
author_facet |
VUORI, SAKU K. V. LUTTINEN, ARTO |
author_sort |
VUORI, SAKU K. |
title |
The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica |
title_short |
The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica |
title_full |
The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica |
title_fullStr |
The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica |
title_full_unstemmed |
The Jurassic gabbroic intrusions of Utpostane and Muren: insights into Karoo-related plutonism in Dronning Maud Land, Antarctica |
title_sort |
jurassic gabbroic intrusions of utpostane and muren: insights into karoo-related plutonism in dronning maud land, antarctica |
publisher |
Cambridge University Press (CUP) |
publishDate |
2003 |
url |
http://dx.doi.org/10.1017/s0954102003001287 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102003001287 |
long_lat |
ENVELOPE(-14.000,-14.000,-73.167,-73.167) ENVELOPE(-15.667,-15.667,-73.917,-73.917) ENVELOPE(-15.000,-15.000,-73.733,-73.733) |
geographic |
Dronning Maud Land Vestfjella Utpostane Muren |
geographic_facet |
Dronning Maud Land Vestfjella Utpostane Muren |
genre |
Antarc* Antarctic Science Antarctica Dronning Maud Land |
genre_facet |
Antarc* Antarctic Science Antarctica Dronning Maud Land |
op_source |
Antarctic Science volume 15, issue 2, page 283-301 ISSN 0954-1020 1365-2079 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0954102003001287 |
container_title |
Antarctic Science |
container_volume |
15 |
container_issue |
2 |
container_start_page |
283 |
op_container_end_page |
301 |
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1792507286162243584 |