Petrogenesis of Hercynian leucogranites from the southern Armorican Massif: contribution of REE and isotopic (Sr, Nd, Pb and O) geochemical data to the study of source rock characteristics and ages

Chauris, 1977, Les associations paragénétiques dans la métallogénie varisque du Massif armoricain, Mineral. Deposita, 12, 353, 10.1007/BF00206172 Cathelineau, 1982, les gisements d'uranium liés spatialement aux leucogranites sud-armoricains etàleur encaissant métamorphique, Mém. Sci. Terre, 42 Lameyre, 1980, Les magmas granitiques: leurs comportements, leurs associations et leurs sources, Mem. Hors Sér. Soc. Geol. Fr. 10, 51 de La Roche, 1980, Les granitesàdeux micas hercyniens français. Essais de cartographie et de corrélations géochimiques appuyés sur une banque de données. Implications pétrologiques et métallogéniques, Sci. Terre, 24, 5 Debon, 1983, A Chemical-mineralogical classification of common plutonic rocks and associations, Trans. R. Soc. Edinburgh, Earth Sci., 73, 135, 10.1017/S0263593300010117 Cogné, 1974, Le Massif armoricain, 105 Auvray, 1979, Genèse etévolution de la crouˆte continentale dans le nord du Massif armoricain, 681 Vidal, 1980, L'évolution polyorogénique du Massif armoricain: apport de la géochronologie et de la géochimie isotopique du strontium, Mem. Soc. Geol. Mineral. Bretagne, 21, 162 Peucat, 1981, Late Proterozoic zircon ages from a basic-ultrabasic complex: a possible Cadomian orogenic complex in the Hercynian belt of Western Europe, Geology, 9, 169, 10.1130/0091-7613(1981)9<169:LPZAFA>2.0.CO;2 Doré, 1972, La transgression majeure du Paléozoïque inférieur dans le Nord-Est du Massif armoricain, Bull. Soc. Geol. Fr. 14, 79, 10.2113/gssgfbull.S7-XIV.1-5.79 Adams, 1967, K/Ar ages from the basement complex of the Channel Islands (United Kingdom) and the adjacent French island, Earth Planet. Sci. Lett., 2, 52, 10.1016/0012-821X(67)90172-0 Auvray, 1973, Chronologie desévénements géologiques dans le Trégor (Bretagne septentrionale), lère R.A.S.T. Paris, 54 Calvez, 1978, Two billion years relicts in the Hercynian belt of Western Europe, Contrib. Mineral. Petrol., 65, 395, 10.1007/BF00372286 Auvray, 1980, Données nouvelles sur le Protérozoïque inférieur du domaine nord-armoricain (France):aˆge et signification, Can. J. Earth Sci., 17, 532, 10.1139/e80-050 Vidal, 1981, Precambrian relicts in the Armorican Massif. Their age and role in the evolution of the Western and Central European Cadomian-Hercynian belt, Precambrian Res., 14, 1, 10.1016/0301-9268(81)90032-2 Le Corre, 1977, Le Briovérien de Bretagne centrale: essai de synthèse lithologique et structurale, Bur. Rech. Geol. Min. Bull., Sect. 1, 3, 219 Chauris, 1969, Sur un important accident structural dans le Nord-Ouest de l'Armorique, C.R. Acad. Sci. Paris, 268, 2859 Cogné, 1960, Schistes cristallins et granites en Bretagne méridionale: le domaine de l'anticlinal de Cornouaille, Thèse Universitéde Strasbourg, Mém. Carte Géol. Fr. Paris Vidal, 1973, Premières données géochronologiques sur les granites hercyniens du Sud du Massif armoricain, Bull. Soc. Geol. Fr., Sér. 7, 15, 239, 10.2113/gssgfbull.S7-XV.3-4.239 Audren, 1976, Mobilisation anatectique et déformation. Un exemple: les migmatites du Golfe du Morbihan (Bretagne méridionale), Bull. Soc. Geol. Fr., Sér. 7, 18, 1041, 10.2113/gssgfbull.S7-XVIII.4.1041 Cogné, 1977, La chaîne hercynienne ouest-européenne correspond-elleàun orogène per collision? Propositions pour une interprétation géodynamique globale, 268, 111 Peucat, 1979, Définition géochronologique de la phase bretonne en Bretagne centrale:étude RbSr de granites du domaine centre armoricain, Bull. B.R.G.M., Spécial “Colloque 80”, 1, 349 Carpenter, 1976, Hercynian high pressure/low temperature metamorphism in the Ile de Groix blueschists, Nature, 262, 276, 10.1038/262276a0 Peucat, 1977, Geochronology of some blueschists fromîle de Groix, France, Nature, 268, 131, 10.1038/268131a0 Peucat, 1982, Precambrian UPb zircon ages of eclogites and garnet pyroxenites from South Brittany (France): an old oceanic crust in the West European Hercynian Belt?, Earth Planet. Sci. lett., 60, 70, 10.1016/0012-821X(82)90021-8 Montigny, 1974, A la recherche des océans perdus: leséclogites de Vendée, témoins métamorphisés d'une ancienne crouˆte océanique, C.R. Acad. Sci. Paris, Sér. D, 297, 543 Godard, 1981, Lambeaux probables d'une crouˆte océanique subductée: leséclogites de Vendée (Massif armoricain, France), 153 Bernard-Griffiths, 1982, Eclogites et gabbros associés dans la partie armoricaine de la chaîne hercynienne: données géochimiques (Terres Rares) et isotopiques (Sr, Nd), Terra Cognita, 2, 323 J. Bernard-Griffiths and J. Cornichet, Origin of eclogites from South Brittany: a SmNd isotopic and REE study, Chem. Geol. (Isot. Geosci. Sect.) 52 (in press). J.L. Paquette, J.J. Peucat, J. Bernard-Griffiths, and J. Marchand, Evidence for basement relicts shown by UPb zircon dating of eclogites and associated rocks in the Hercynian belt of South Brittany (France), Chem. Geol. (Isot. Geosci. Sect.) 52 (in press). Cogné, 1960, Métamorphismes et granitisations en liaison avec l'évolution orogénique en Bretagne méridionale, Soc. Géol. Fr. Bull., Sér. 7, 3, 213, 10.2113/gssgfbull.S7-II.2.213 Vigueresse, 1978, Gravimétrie et granites armoricains. Structure et mise en place des granites hercyniens Berthé, 1979, Orthogneiss, mylonite and non coaxial deformation of granite: the example of the South Armorican shear zone, J. Struct. Geol., 1, 31, 10.1016/0191-8141(79)90019-1 Jégouzo, 1980, The South armorican shear zone, J. Struct. Geol., 2, 39, 10.1016/0191-8141(80)90032-2 Choukroune, 1983, Cisaillement ductile sud-armoricain et déformations discontinues associées: mise enévidence de la déformation régionale non coaxiale dextre, C.R. Acad. Sci. Paris, 296, 657 Lefort, 1982, The southern part of the armorican orogeny: a result of crustal shortening related to reactivation of a pre-Hercynian mafic belt during carboniferous time, Tectonophysics, 89, 359, 10.1016/0040-1951(82)90143-3 Brun, 1979, Strain heating in continental shear zones: a review, 36 Strong, 1981, The leucogranites of Southern Brittany: origin by faulting, fractional heating, fluid flux and fractional melting, Can. Mineral., 19, 163 J.J. Peucat and P. Jégouzo, Isotopic and age zoning of leucogranites from the hercynian belt of West Europe (South Armorican massif, France) (in preparation). Jahn, 1980, Nd and Sr isotopic compositions and REE abundances of Cretaceous MORB (Holes 417 D and 418 A, Legs 51 52 and 53), Earth Planet. Sci. Lett., 48, 171, 10.1016/0012-821X(80)90180-6 De Albuquerque, 1977, Geochemistry of the tonalitic and granitic rocks of the Nova Scotia Southern plutons, Geochim. Cosmochim. Acta, 41, 1, 10.1016/0016-7037(77)90183-1 Cocherie, 1978, Géochimie des terres rares dans les granitoïdes Kistler, 1981, Petrogenesis of garnet two-mica granites in the Ruby Mountains, Nevada, J. Geophys. Res., 86, 10591, 10.1029/JB086iB11p10591 Strong, 1982, Rare earth elements in the bimodal Mont Peyton batholit: evidence of crustal anatexis by mantle-derived magma, Can. J. Earth Sci., 19, 308, 10.1139/e82-022 Vidal, 1982, Geochemical investigations of the origin of the Manaslu leucogranite (Himalaya, Nepal), Geochim. Cosmochim. Acta, 46, 2279, 10.1016/0016-7037(82)90201-0 Fourcade, 1980, Les granitoïdes de France. Les granites des Pyrénées, C. Typologie des granitoïdes basée sur les concentrations en terres rares, 75 Chauvel, 1982, Géochimie isotopique (Nd, Sr) et géochimie deséléments traces des basaltes alcalins du Massif Central français: contraintes pétrogénétiques et arguments en faveur du métosomatisme mantellique, 180 Allègre, 1980, NdSr isotopic relationship in granitoid rocks and continental crust development: a chemical approach to orogenesis, Nature, 286, 335, 10.1038/286335a0 Ph. Vidal, J. Bernard-Griffiths, A. Cocherie, P. Le Fort, J.J. Peucat and S.M.F. Sheppard, Geochemical comparison between Himalayan and Hercynian leucogranites, Phys. Earth Planet. Inter. (in press). Montgomery, 1979, Uranium-lead geochronology of the Archean Imataca Series, Venezuela Guayana shield, Contrib. Mineral. Petrol., 69, 167, 10.1007/BF00371859 Moorbath, 1981, Origin of granitic magma by crustal remobilisation: RbSr and PbPb geochronology and isotope geochemistry of the late Archean Qoˆrqut granite complex of southern West Greenland, Geochim. Cosmochim. Acta, 45, 1045, 10.1016/0016-7037(81)90131-9 J.J. Peucat and Ph. Vidal, “Isotopic amnesia”?: Do isotopes fail to record premetamorphic events?, in: The Precambrian in Younger Fold Belts, Zoubek, ed., Wiley (in press). Ludwig, 1977, Lead-isotope inhomogeneity in Precambrian igneous K-feldspars, Geochim. Cosmochim. Acta, 41, 1457, 10.1016/0016-7037(77)90251-4 Vidal, 1980, UPb and RbSr systematics of the Suomussalmi Archean Greenstone belt (Eastern Finland), Geochim. Cosmochim. Acta, 44, 2033, 10.1016/0016-7037(80)90201-X Michard-Vitrac, 1981, Lead isotopic composition of Hercynian granitic K-feldspars constraints for continental genesis, Nature, 291, 460, 10.1038/291460a0 Meijer, 1976, Pb and Sr isotopic data bearing on the origin of volcanic rocks from the Mariana islands arc system, Geol. Soc. Am. Bull., 87, 1358, 10.1130/0016-7606(1976)87<1358:PASIDB>2.0.CO;2 Sun, 1980, Lead isotopic study of young volcanic rocks from mid-ocean ridges, ocean islands and island arcs, Philos. Trans. R. Soc. London, 297, 409, 10.1098/rsta.1980.0224 Doe, 1979, Plumbotectonics, the Phanerozoic, 22 Clayton, 1963, The use of bromine penta-fluoride in the extraction of oxygen from oxides and silicates for isotopic analysis, Geochim. Cosmochim. Acta, 27, 43, 10.1016/0016-7037(63)90071-1 Taylor, 1978, Oxygen and hydrogen isotope studies of plutonic granitic rocks, Earth Planet. Sci. Lett., 38, 177, 10.1016/0012-821X(78)90131-0 Sheppard, 1977, The Cornubian batholith, SW England:D/H and18O/16O studies of kaolinite and other alteration minerals, J. Geol. Soc., 133, 573, 10.1144/gsjgs.133.6.0573 Albarède, 1980, 18O/16O evidence for noncogenetic magmas associated in a 300 Ma old concentric pluton at Ploumanac'h (Brittany, France), J. Geol. Soc. London, 137, 641, 10.1144/gsjgs.137.5.0641 Turpin, 1984, Altérations hydrothermales et caractérisation isotopique (OHC) des minéraux et des fluides dans le massif uranifère de St. Sylvestre—extensionàd'autres gisements intragranitiques d'uranium français Turpin, 1983, Stable isotope studies on Saint-Sylvestre granitic complex and associated uranium mineralization (Limousin, Massif Central français), Terra Cognita, 3, 176 Hoefs, 1983, The oxygen isotope composition of Hercynian granites and pre-Hercynian gneisses from the Schwarzwald, SW Germany, Contrib. Mineral. Petrol., 83, 320, 10.1007/BF00371200 Krogh, 1973, A low-contamination method for decomposition of zircon and the extraction of U and Pb for isotopic age determinations, Geochim. Cosmochim. Acta, 37, 485, 10.1016/0016-7037(73)90213-5 Peucat, 1983, Géochronologie des roches métamorphiques (RbSr et UPb). Exemples choisis au Groënland, en Laponie, dans le Massif armoricain et en Grande Kabylie, Mém. Soc. Géol. Min. Bretagne, 28, 158 Chappell, 1974, Two contrasting granite types, Pacific Geol., 8, 173 Gromet, 1983, Rare earth element distributions among minerals in a granodiorite and their petrogenetic implications, Geochim. Cosmochim. Acta, 47, 925, 10.1016/0016-7037(83)90158-8 McCulloch, 1978, SmNd and RbSr chronology of continental crust formation, Science, 200, 1003, 10.1126/science.200.4345.1003 DePaolo, 1981, A neodymium and strontium isotopic study of the Mesozoic calc-alkaline granitic batholiths of the Sierra Nevada and Peninsular Ranges, California, J. Geophys. Res., 86, 10470, 10.1029/JB086iB11p10470 Weaver, 1980, Continental crust composition and nature of the lower crust: constraints from the mantle NdSr isotope correlation, Nature, 286, 342, 10.1038/286342a0 Nakamura, 1974, Determination of REE, Ba, Fe, Mg, Na and K in carbonaceous and ordinary chondrites, Geochim. Cosmochim. Acta, 38, 757, 10.1016/0016-7037(74)90149-5