Abstract
THE Ile de Groix series consists of metavolcanic and metasedimentary rocks, with or without glaucophane. These rocks belong to a South Brittany polymetamorphic complex which is named the ‘domaine de l'Anticlinal de Cornouaille’ by Cogné1. In this complex, anatectic granites occur in the midst of a migmatitic and gneissic terrain1,2. Some meta-sedimentary and metavolcanic rocks which occur in the terrain are cut by Hercynian granites. The Ile de Groix series1,3,4 is characterised by high pressure mineral assemblages with glaucophane, jadeitic pyroxene and lawsonite5—these assemblages are unknown on the adjacent mainland. The series is considered to have formed during two metamorphic periods: the first produced high pressure–low temperature mineral assemblages and the second produced a recrystallisation of mineral assemblages in greenschist facies6. In this note, we shall present new isotopic age data on various rocks and minerals from Ile de Groix, hoping to delineate the time sequence of original magmatism, sedimentation and subsequent metamorphism.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Cogné, J. Mém. Serv. carte geol. Fr. 382 (1960).
Audren, C. & Le Metour, J. Bull. Soc. Geol. France. (7), 18, 1041–1049 (1976).
Felix, C. Annales Soc. geol. Belgique T. 95, (1972); 345–391, (1973).
Makanjuola, A. A. & Howie, R. A. Contr. miner. Petrol. 35, 83–118 (1972).
Cogné, J., Ruhland, M. & Jeannette, D. Bull. Serv. carte Als. Lorr. 93, 370–385 (1966).
Triboulet, C. Contr. miner. Petrol. 45, 65–90 (1974).
Jäger, E. Eclogae geol. Helv. 63/1, 163–172 (1970); Hunziker, J. C. Eclogae geol. Helv. 63/1, 151–161 (1970).
Carpenter, M. S. N. & Civetta, L. Nature 262, 276–277 (1976).
Maluski, H. C.R. Acad. Sci., Paris, 283, 223–226 (1976).
Coleman, R. G. & Lanphere, M. A. Geol. Soc. Am. Bull. 82, 2397–2412 (1971).
Suppe, J. & Armstrong, R. L. Am. J. Sci. 272, 217, 233 (1972).
Hunziker, J. C. Mem. Inst. Geol. Miner. Padova 31, 54 (1974).
Vidal, Ph. Bull. Soc. geol. miner. Bretagne (C), IV, 2, 75–89 (1972).
Clauer, N. & Bonhomme, M. Bull. Serv. Carte geol. Als. Lorr. 23, 191–208 (1970).
Gebauer, D. & Grunenfelder, M. Contr. miner. Petrol. 59, 13–32 (1976).
Calvez, J. Y. Thése 3e cycle Rennes (1976).
Vidal, Ph. Bull. Soc. Geol. France. (7), 15 (1973).
Vidal, Ph. Thèse d'Etat, Rennes (1976).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
PEUCAT, J., COGNE, J. Geochronology of some blueschists from Ile de Groix, France. Nature 268, 131–132 (1977). https://doi.org/10.1038/268131a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/268131a0
This article is cited by
-
Discovery of an albite gneiss from the Ile de Groix (Armorican Massif, France): geochemistry and LA-ICP-MS U–Pb geochronology of its Ordovician protolith
International Journal of Earth Sciences (2012)
-
A Sm-Nd isotopic study of 500 Ma old oceanic crust in the Variscan belt of Western Europe: the Chamrousse ophiolite complex, Western Alps (France)
Contributions to Mineralogy and Petrology (1987)
-
U-Pb dating of an early paleozoic bimodal magmatism in the french Massif Central and of its further metamorphic evolution
Contributions to Mineralogy and Petrology (1982)
-
Intense progressive shear in Ile de Groix blueschists and compatibility with subduction or obduction
Nature (1978)
-
Age and tectonic implications of the Baie d'Audierne basic-ultrabasic complex
Nature (1977)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.
