Lyell Collection

Geological Society, London, Special Publications

Lyell Centre  |   Lyell Collection  |   Subscriptions   |   Geological Society  |   Email alerts  |   Online bookshop  |   Help


Keywords:
Author:
Advanced search>>
This Article
Right arrow Full Text (PDF)
Right arrow References
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Perini, G.
Right arrow Articles by Doblas, M.
Right arrow Search for Related Content
GeoRef
Right arrow GeoRef Citation
Geological Society, London, Special Publications; 2004; v. 223; p. 415-438;
DOI: 10.1144/GSL.SP.2004.223.01.18
© 2004 Geological Society of London

Carboniferous-Permian mafic magmatism in the Variscan belt of Spain and France: implications for mantle sources

G. Perini1,2, J. M. Cebria2, J. Lopez-Ruiz2 & M. Doblas2

1 Dipartimento di Scienze della Terra, Università di Firenze, Via La Pira 4, 50121 Firenze, Italy gperini{at}steno.geo.unifi.it
2 Departamento de Geología, Museo Nacional de Ciencias Naturales, CSIC, Jose Gutierrez Abascal 2, 28006 Madrid, Spain

Carboniferous-Permian magmatism in the Spanish Central System, Iberian Ranges, Cantabrian Chain, Pyrenees (Maladeta plutonic complex) and the French Massif Central includes a range of mafic calc-alkaline and shoshonitic rock types, as well as amphibole-bearing lamprophyres (spessartites) and minor alkaline lamprophyres (camptonites). Subalkaline basalts with intermediate characteristics between enriched mid-ocean ridge basalts (E-MORB) and the mafic calc-alkaline rocks also occur in the Pyrenees (Panticosa, Cinco Villas and La Rhune). The incompatible trace-element characteristics of the least differentiated subalkaline rocks and lamprophyres indicate that variably enriched mantle sources were involved in their genesis. High large ion lithophile element/high-field-strength element (LILE/HFSE), light rare earth element (LREE) HFSE and low Ce/Pb ratios in the calc-alkaline and shoshonitic rocks require either assimilation of crustal rocks plus fractional crystallization (AFC) of the parental mafic magmas or melting of a previously subduction-modified mantle source. In the Cantabrian Chain and the Massif Central, melting of a subduction-modified mantle source seems more likely. In the Central System, Iberian Ranges and Maladeta area the lack of any evidence for a contemporaneous subduction system suggests that AFC processes were more likely to be responsible for the crustal signature of the magmas. The alkaline camptonites from the Central System were generated from an enriched mantle source, which had lower LREE/HFSE and LILE/HFSE ratios than the source of the older calc-alkaline magmas from the same area. The incompatible trace-element patterns and ratios (e.g., Y/Nb, Zr/Nb) of the subalkaline basalts from Panticosa, Cinco Villas and La Rhune suggest that they were generated from similar parent magmas, formed by mixing of partial melts of an asthenospheric source and a crustal component.





This article has been cited by other articles:


Home page
Geological Society, London, Special PublicationsHome page
D. Orejana and C. Villaseca
Heterogeneous metasomatism in cumulate xenoliths from the Spanish Central System: implications for percolative fractional crystallization of lamprophyric melts
Geological Society, London, Special Publications, 2008; 293: 101 - 120.
[Abstract] [Full Text] [PDF]


Home page
Geological Society, London, Special PublicationsHome page
G. Galan, V. Oliveras, and B. A. Paterson
Types of metasomatism in mantle xenoliths enclosed in Neogene-Quaternary alkaline mafic lavas from Catalonia (NE Spain)
Geological Society, London, Special Publications, 2008; 293: 121 - 153.
[Abstract] [Full Text] [PDF]