Skip to main content
SpringerLink
Log in

The role of hybridization in the genesis of Hercynian granitodis in the gredos massif, Spain: inferences from Sr-Nd isotopes

  • Published:
Contributions to Mineralogy and Petrology Aims and scope Submit manuscript

Abstract

The Gredos massif is one the better exposed granitoid complexes of the Iberian massif. It is composed mainly of peraluminous granitoids with subordinate basic and ultrabasic complexes. The massif also contains mega-enclaves of migmatites with which the granitoids show transitional contacts. Two major magmatic associations have been distinguished in this study: (1) One comprises the granitoids with microgranular enclaves, the enclaves, and basic rocks; (2) the other is formed by leucogranites, intrusive into the former series and free of microgranular enclaves. Field relationships and microstructures indicate that the rocks of the first series are related by a dominant hybridization process. The Sr-Nd isotopic study reveals that this process is complex, relating different end-members of mantle and crustal affinities, and occurred around 295 Ma ago, late with respect to the main deformation phases of the Hercynian orogeny. The granitoids with microgranular enclaves (GME) are part of an overall mixing trend involving Palaeozoic mantle-derived magma and melts of older crustal material. Amphibole-bearing GME, in general, contain greater proportions of the mantle-derived component than the cordierite-bearing GME. The actual mixing processes took place on a variety of scales, sometimes between melts which were themselves hybrids. On a local scale this hybridization process can be modelled by simple binary mixing as documented in the case of a composite dyke. The isotopic signatures of the basic rocks are probably, to a large degree, the result of interaction with crustal melts, though additionally the presence of an enriched mantle source cannot be elmininated. Microgranular enclaves and their immediate hosts have differing initial Sr and Nd isotopic signatures, indicating that isotopic equilibrium was not attained. This suggests that the enclaves did not reside in their final granitic melt for long before cooling of the whole system. The enclaves are considered to have been derived from basaltic melts which had fractionated and hybridised to varying degrees. Late-stage peraluminous leucogranites have similar initial Nd isotopic compositions to the evolved GME; a crustal source with a radically different Nd isotopic composition or age does not need to be invoked in their petrogenesis.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Allègre CJ, Ben-Othman D (1980) Nd-Sr isotopic relationship in granitoid rocks and continental crust development: a chemical approach to orogenesis. Nature 286:335–341

    Google Scholar 

  • Aparicio A, Barrera JL, Caraballo JM, Peinado M, Tinao JM (1975) Los materials graníticos del Sistema Central Español. Mem I G M E 88:1–145

    Google Scholar 

  • Bea F, Moreno-Ventas I (1985) Estudio petrológico de los granitoides del área centro-norte de la Sierra de Gredos (Batolito de Avila: Sistema Central Español). Stud Geol Salmant XX: 137–174

    Google Scholar 

  • Bea F, Sánchez JG, Serrano-Pinto M (1987) Una compilación geoquímica (elementos mayores) de los granitoides del macizo Hespérico. In: Bea F, Carnicero A, Gonzalo JC, López-Plaza M, Roíguez MD (eds) Geologia de los granitoides y rocas básicas asociadas del Macizo Hespérico. Rueda, Madrid, pp 87–194

    Google Scholar 

  • Ben-Othman D, Fourcade S, Allègre CJ (1984) Recycling processes in granite-granodiorite complex genesis: the Querigut case studied by Nd-Sr isotope systematics. Earth Planet Sci Lett 69:290–300

    Google Scholar 

  • Bernard-Griffiths J, Peucat J, Sheppard S, Vidal P (1985) 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. Earth Planet Sci Lett 74: 235–250

    Google Scholar 

  • Bickle MJ, Wickham SM, Chapman HJ, Taylor Jr (1988) A strontium, neodymium and oxygen isotope study of hydrothermal metamorphism and crustal anatexis in the Trois Seigneurs Massif, Pyrenees, France. Contrib Mineral Petrol 100:399–417

    Google Scholar 

  • Blake S, Koyaguchi T (1991) Insights on the magma mixing model from volcanic rocks. In: Didier J, Barbarin B (eds) Enclaves and granite petrology. Elsevier, Amsterdam, pp 403–413

    Google Scholar 

  • Calvez JY, Vidal Ph (1978) Two billion years old relicts in the Hercynian belt of western Europe. Contrib Mineral Petrol 65:395–399

    Google Scholar 

  • Capdevila R (1969) Le métamorphisme régional progressive et les granites dans le segment Hercyniene de Galice nord oriental (NW de l'Espagne). Thèse d'etat, Univ Montpellier

  • Capdevila R, Floor P (1970) Les différents types de granites hercyniens et leur distribution dans le Nord-Ouest de l'Espagne. Bol Geol Min España LXXXI:215–225

    Google Scholar 

  • Capdevila R, Corretgé G, Floor P (1973) Les granitoides varisques de la Meseta Ibérique. Bull Soc Geol Fr XV-3-4:209–228

    Google Scholar 

  • Carter SR, Evensen NM, Hamilton PJ, O'Nions RK (1978) Neodymium and strontium isotope evidence for crustal contamination of continental volcanis. Science 202:743–746

    Google Scholar 

  • Casillas R (1989) Las asociaciones plutónicas tardihercínicas del sector occidental de la Sierra de Guadarrama-Sistema Central Español (Las Navas del Marqués-S. Martín de Valdeiglessias): petrología, geoquímica, genesis y evolución. Tesis doctoral, Univ Madrid

  • Castro A, de la Rosa J, Stephens WE (1990) Magma mixing in the subvolcanic environment: petrology of the Gerena interaction zone near Seville, Spain. Contrib Mineral Petrol 105:9–26

    Google Scholar 

  • Castro A, Moreno-Ventas I, de la Rosa J (1991) H-type (hybrid) granitoids: a proposed revision of the granite-type classification and nomenclature. Earth-Sci Rev 31:237–253

    Google Scholar 

  • Chappell BW, White AJR (1974) Two contrasting granite types. Pac Geol 8:173–174

    Google Scholar 

  • Corretgé LG (1983) Las rocas graníticas y granitoides del Macizo Ibérico. In: Geología de España. Libro Jubilar JM Rios, tomo I, IGME, pp 569–593

  • Davies G, Gledhill A, Hawkesworth CJ (1985) Upper crustal recycling in southern Britain: evidence from Nd and Sr isotopes. Earth Planet Sci Lett 75:1–12

    Google Scholar 

  • Debon F, Le Fort P (1983) A chemical-minearalogical classification of common plutonic rocks and associations. Philos Trans R Soc Endinburgh 73:135–149

    Google Scholar 

  • DePaolo DJ (1979) Implications of correlated Nd and Sr isotopic variations for the chemical evolution of the crust and mantle. Earth Planet Sci Lett 43:201–211

    Google Scholar 

  • De Paolo DJ, Wasserburg GJ (1979) Sm-Nd age of the Stillwater complex and mantle evolution curve for neodymium. Geochim Cosmochin Acta 43:999–1008

    Google Scholar 

  • Doblas M (1990) Estudio de las deformaciones tardiherćinicas de los granitoides de un sector del Sistema Central Español (Zona Central de Gredos y áreas adyacentes). Tesis doctoral, Univ Complutense de Madrid

  • Downes H, Duthou J-L (1988) Isotopic and trace-element arguments for the lower-crustal origin of Hercynian granitoids and pre-Hercynian orthogneises, Massif Central (France). Chem Geol 68:291–308

    Google Scholar 

  • Duthou JL, Pin C (1988) Sr, Nd isotope geochemistry of Hercynian granitoids from the western Massif Central (France). Soc Ital Mineral Petrol 43:525–530

    Google Scholar 

  • Eberz GW, Nicholls IA, Mass R, McCulloch MT, Whitford DJ (1990) The Nd- and Sr-isotopic composition of I-type microgranitoid enclaves and their host rocks from the Swifts Creek Pluton, southeast Australia. Chem Geol 85:119–134

    Google Scholar 

  • Floor P, Kisch HJ, Oen Ing Soen (1970) Essai de correlation de quelques granites hercyniens de la Galice et du Nord du Portugal. Bol Geol Min España IXXXI:242–244

    Google Scholar 

  • Fourcade S, Javoy M (1991) Sr-Nd-O isotopic features of mafic microgranular enclaves and host granitoids from the Pyrenees, France: evidence for their hybrid nature and inference on their origin. In: Didier J, Barbarian B (eds) Enclaves and granite petrology. Elsevier, Amsterdam, pp 345–364

    Google Scholar 

  • García de Figuerola LC, Ugidos JM, Bea F, Carnicero A, Franco P, Rodríguez D, López-Plaza M (1980) Plutonism of Central Western Spain. A preliminary note. Estud Geol 36:339–348

    Google Scholar 

  • Guerrot C, Peucat JJ, Capdevilla R, Dosso L (1989) Archaean protoliths within early Proterozoic granulitic crust of the west European Hercynian belt: possible relics of the west African craton. Geology 17:241–244

    Google Scholar 

  • Halliday AN, Fallick AE, Hutchinson J, Hidreth W (1984) A Nd, Sr and O isotopic investigation into the causes of chemical and isotopic zonation in the Bishop Tuff, California. Earth Planet Sci Lett 68:379–391

    Google Scholar 

  • Hawkesworth CJ, Vollmer R (1979) Crustal contamination versus enriched mantle: 143Nd/144Nd and 87Sr/86Sr evidence from the Italian volcanics. Contrib Mineral Petrol 69:151–165

    Google Scholar 

  • Holden P, Halliday AN, Stephens WE (1987) Neodymium and strontium isotope content of microdiorite enclaves points to mantle input to granitoid production. Nature 330:53–56

    Google Scholar 

  • Irvine TN, Baragar WRA (1971) A guide to the chemical classfication of the common volcanic rocks. Can J Earth Sci 8:523–548

    Google Scholar 

  • Julivert M, Fontboté JMa, Ribeiro A, Nabais Conde LE (1972) Mapa tectónico de la Península Ibérica y Baleares. E. 1:1000000. Inst Geol Min Esp Mapa Geol Esp

  • Julivert M, Fontboté JMa, Ribeiro A, Nabais Conde LE (1974) Memoria explicativa del mapa tectónico de la Península Ibérica y Baleares: 1-113. Inst Geol Min Esp Mapa Geol Esp

  • Kober B, Lippolt HJ (1985) Pre-Hercynian Pb transfer to basement rocks as indicated by Pb isotopes of Schwarzwald crystalline, SW Germany, I, II. Contrib Mineral Petrol 90:162–178

    Google Scholar 

  • Lameyer J (1966) Leucogranites et muscovitisation dans le Massif Central français. Ann Fac Sc Univ Clermont-Ferrand 29, 264pp

  • Lemeyre J (1987) Las rocas graníticas de la Cadena Hercinica en el sector francés. In: F Bea, A Carnicero, JC Gonzalo, M López Plaza, MD Rodriguez Alonso (eds) Geología de los Granitoides y Rocas Asociadas del Macizo Hespérico. Rueda, Madrid

    Google Scholar 

  • Lesher CE (1990) Decoupling of chemical and isotopic exchange during magma mixing. Nature 344:235–237

    Google Scholar 

  • Liew TC, Hofmann AW (1988) Precambrian crustal components, plutonic associations, plate environment of the Hercynian Fold Belt of central Europe: indications from a Nd and Sr isotopic study. Contrib Mineral Petrol 98:129–138

    Google Scholar 

  • Lotze F (1945) Zur Gliederung der Varisziden der iberischen Meseta. Geotecktonische Forsch 6:78–92

    Google Scholar 

  • Mendes F, Fuster JM, Ibarrola E, Fernández Santín S (1972) L'âge de quelques granites de la Sierra de Gaudarrama (Systéme Central Espagnol). Rev Fac Ci Lisboa 16 (1):345–365

    Google Scholar 

  • Michard-Vitrac A, Albarede F, Allègre CJ (1981) Lead isotopic composition of Hercynian granitic K-feldspars constraints continental genesis. Nature 291:460–464

    Google Scholar 

  • Middlemost EAK (1975) The basalt clan. Earth Sci Rev 11:337–364

    Google Scholar 

  • Miyashiro A (1974)_Volcanic rock series in island arcs and active continental margins. Am J Sci 274:321–355

    Google Scholar 

  • Moreno-Ventas I (1991) Petrología de los granitoides y rocas bácicas de la Sierra de Gredos. Tesis doctoral, Univ Sevilla

  • Paquette JL, Peucat J-J, Bernard-Griffiths J, Marchand J (1985) Evidence of old Precambrian relics shown by U-Pb zircon dating of eclogites and associated rocks in the Hercynian belt of south Brittany, France. Chem Geol Isot Geosci 52: 203–216

    Google Scholar 

  • Pearce JA, Harris NBW, Tindle AG (1984) Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. J Petrol 25:956–983

    Google Scholar 

  • Peccerilo R, Taylor SR (1976) Geochemistry of Eocene calc-alkaline volcanic rocks from the Kastamonu area, northern Turkey. Contrib Mineral Petrol 58:63–81

    Google Scholar 

  • Peucat JJ, Jegouzo P, Vidal P, Bernard-Griffiths J (1988) Continental crust formation seen through the Sr and Nd isotope systematics of S-type granites in the Hercynian belt of western France. Earth Planet Sci Lett 88:60–68

    Google Scholar 

  • Pin C, Duthou J-L (1990) Sources of Hercynian granitoids from the French Massif Central: inferences from Nd isotopes and consequences for crustal evolution. Chem Geol 83:281–296

    Google Scholar 

  • Pin C, Binon M, Belin JM, Barbarin B, Clements JD (1990) Origin of microgranular enclaves in granitoids: equivocal Sr-Nd evidence from Hercynian rocks in the Massif Central. J Geophys Res B95:17821–17828

    Google Scholar 

  • Sparks RSJ, Marshall LA (1986) Thermal and mechanical constraints on mixing between mafic and silicic magmas. J Volcanol Geothermal Res 29:99–124

    Google Scholar 

  • Thy P (1983) Spinel minerals in transitional and alkali basaltic glasses from Iceland. Contrib Mineral Petrol 83:141–149

    Google Scholar 

  • Teixeira C, Gonçalves F (1980) Introduçao a geologia da Portugal I N I C Lisboa: 1–476

  • Turpin L, Cuney M, Friedrich M, Bouchez J-L, Aubertin M (1990) Meta-igneous origin of Hercynian peraluminous granites in N.W. French Massif Central: implications for crustal history reconstructions. Contrib Mineral Petrol 104:163–172

    Google Scholar 

  • Udigos JM (1973) Estudio petrológico del área Bejar-Plasencia (Salamanca Cáceres). Tesis doctoral, Univ Salamanca

  • Vialette Y, Bellido F, F∭ter JMa, Ibarrola E (1981) Données geochronologiques sur les granites de la Cabrera. Cuad Geol Iberia 7:327–335

    Google Scholar 

  • Vidal Ph, Peucat JJ, Lasnier B (1980) Dating of granulities involved in the hercynian fold-belt of Europe: an example taken from the granulite-facies orthogneisses at La Picherais, southern Armorican massif, France. Contrib Mineral Petrol 72:283–289

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Departamento de Geología y Minería, Universidad de Sevilla, E-21819 Palos de la Frontera, Huelva, Spain

    Iñaki Moreno-Ventas & Antomo Castro

  2. Isotope Geology Unit, Scottish Universities Research and Reactor Center, East Kilbride, G75 0QU, Glasgow, UK

    Iñaki Moreno-Ventas & Graeme Rogers

Authors
  1. Iñaki Moreno-Ventas
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Graeme Rogers
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Antomo Castro
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Moreno-Ventas, I., Rogers, G. & Castro, A. The role of hybridization in the genesis of Hercynian granitodis in the gredos massif, Spain: inferences from Sr-Nd isotopes. Contrib Mineral Petrol 120, 137–149 (1995). https://doi.org/10.1007/BF00287111

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00287111

Keywords

Search

Navigation