Dronning Maud Land Jurassic volcanism : volcanology and petrology

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Luttinen , A 2021 , Dronning Maud Land Jurassic volcanism : volcanology and petrology . in J L Smellie , K S Panter & A Geyer (eds) , VOLCANISM IN ANTARCTICA: 200 MILLION YEARS OF SUBDUCTION, RIFTING AND CONTINENTAL BREAK-UP : 200 Million Years of Subduction, Rifting and Continental Break-up . , 157 , Geological Society Memoirs , vol. 55 , Geological Society of London , London , pp. 157-181 . https://doi.org/10.1144/M55-2018-89

Title: Dronning Maud Land Jurassic volcanism : volcanology and petrology
Author: Luttinen, Arto
Other contributor: Smellie, J. L.
Panter, K. S.
Geyer, A.
Contributor organization: Department of Geosciences and Geography
Natural Sciences Unit
Publisher: Geological Society of London
Date: 2021-01-27
Language: eng
Number of pages: 25
Belongs to series: VOLCANISM IN ANTARCTICA: 200 MILLION YEARS OF SUBDUCTION, RIFTING AND CONTINENTAL BREAK-UP
Belongs to series: Geological Society Memoirs
ISSN: 0435-4052
DOI: https://doi.org/10.1144/M55-2018-89
URI: http://hdl.handle.net/10138/340246
Abstract: The Jurassic igneous rocks of Dronning Maud Land represent Karoo flood basalt magmatism in Antarctica. Fifty years of research has documented systematic differences between magmas associated with the Karoo rift-zone (Vestfjella and Ahlmannryggen) and the rift-shoulder (Sembberget, Kirwanveggen) settings. The 189–182 Ma rift-zone tholeiites were chemically diverse and mainly formed compound-braided flow fields which record several magnetic polarity reversals. In contrast, the c. 181 Ma rift-shoulder tholeiites were chemically uniform and formed thick tabular sheet lavas within a single normal polarity period. The volcanic architecture! records a long initial phase of slow eruptions from shield volcanoes in the initial rift and a brief phase of voluminous fissure eruptions flooding the rift shoulder. All of the major magma types in the rift-zone and rift-shoulder settings belong to a Nb-depleted category of Karoo flood basalts and were mainly derived from depleted convective upper mantle by magmatic differentiation. Pyroxenite-rich mantle components may have been significant sources for the most enriched magma types. Geochemical fingerprints of recycled crustal material imply that the Nb-depleted Karoo tholeiites may have been derived from mildly subduction-modified parts of the same overall upper-mantle reservoir which has been associated with the Ferrar tholeiites.
Subject: 1171 Geosciences
Peer reviewed: Yes
Usage restriction: openAccess
Self-archived version: acceptedVersion
Funder: SUOMEN AKATEMIA
Grant number:


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