Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-26T04:01:53.082Z Has data issue: false hasContentIssue false
  • English
  • Français

Crustal melting and granite genesis during the Himalayan collision orogenesis

Published online by Cambridge University Press:  03 November 2011

Christian France-Lanord  and
Patrick Le Fort
Christian France-Lanord
Affiliation:
Centre de Recherches Pétographiques et Géochimiques, B.P. 20, 54501 Vandoeuvre-lès-Nancy, France.
Patrick Le Fort
Affiliation:
Centre de Recherches Pétographiques et Géochimiques, B.P. 20, 54501 Vandoeuvre-lès-Nancy, France.
Get access Rights & Permissions [Opens in a new window]

Abstract

This paper reviews the petrogenesis of Himalayan leucogranites (HHγ) on the basis of field, petrological and geochemical data collected over the last fifteen years. HHγ are intruded at the top of the 2 to 8km-thick High Himalayan Crystallines (HHC). These are metamorphosed (Ky to Sill) and present much evidence of partial melting. During the MCT thrusting, the already metamorphosed HHC were thrust on top of the weakly metamorphosed Midland Formations, inducing the main phase of Himalayan metamorphism. The genesis of HHγ and North Himalaya leucogranites (NHγ) associates thrusting along the MCT, propagation of inverted metamorphism, liberation of large quantities of fluid in the Midlands, and partial melting of the HHC.

The restricted compositions of the granites are close to minimum melt compositions; variations in the alkali ratio probably relate to the variable amount of B, F and H2O. The HHγ were issued from the migmatitic zone around 700°C and 800 MPa., and still emplaced some 10 to 15 km below the surface. This syn- to late-tectonic emplacement of the leucogranites lasted for more than 10 Ma according to isotopic ages (25 to 14 Ma).

O, Rb–Sr, Nd–Sm and Pb isotope studies corroborate the unambiguous filiation between the HHC and the leucogranites in central Nepal. They also imply that the plutons are generated as numerous poorly mixed batches of magma produced preferentially in specific zones of the source rock. δD values may be explained by infiltration of water from the Midlands in the melting zone, and/or by water degassing during crystallisation. The positive covariations between Sr-, Nd- and O-isotope ratios relate to the variations in the original sediment composition of the source gneisses. Whereas trace element characteristics often date back to the anatectic process, limited magmatic differentiation is recorded by the biotite. These granites are typical crustal products, keeping track of some of the pre-Himalayan evolution together with that of their own origin.

Keywords

leucogranitemagma batchesmigmatitesOSrNd isotope heterogeneitypartial meltingthrustingwater infiltration
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 79 , Issue 2-3: The Origin of Granites , 1988 , pp. 183 - 195
Copyright
Copyright © Royal Society of Edinburgh 1988

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Albarède, F. & Provost, A. 1977. Petrological and geochemical mass-balance equations: an algorithm for least-square fitting and general error analysis. COMPT GEOSCI 3, 309–326.CrossRefGoogle Scholar
Benard, F., Moutou, P. & Pichavant, M. 1985. Phase relations of tourmaline leucogranites and the significance of tourmaline in silicic magmas. J GEOL 93, 271–91.CrossRefGoogle Scholar
Blamart, D., Graham, C. M. & Sheppard, S. M. F. 1986. The system NaAlSi3O8 (melt)-H2O: solubility of water and hydrogen isotope fractionation factors at 3, 5, and 8 kb (abstract). Inter. Symp. Exp. Mineral. Geochem., Nancy, France, 23–24.Google Scholar
Blattner, P., Dietrich, V. & Gansser, A. 1983. Contrasting 18-O enrichment and origins of High Himalayan and Transhimalayan intrusives. EARTH PLANET SCI LETT 65, 276–86.CrossRefGoogle Scholar
Bonin, B., Lameyre, J. & Le, Fort P. in press. Role of tectonic overthrusting on the vertical mobility of crustal anatectic melts. In Augustithis, S. S. (ed.) Magma crust interaction and evolution. Athens: Theophrastus.Google Scholar
Brunel, M. 1983. Etude pétro-structurale des chevauchements ductiles en Himalaya (Népal oriental et Himalaya du Nord-Quest). Unpublished Thèse Doct. Etat, University of Paris VII.Google Scholar
Brunel, M. & Kienast, J.-R. 1986. Etude pétro-structurale des chevauchements ductiles himalayens sur la transversale de l'Everest-Makalu (Népal oriental). CAN J EARTH SCI 23, 1117–37.CrossRefGoogle Scholar
Burg, J. P. 1983. Tectonogenèse comparée de deux segments de chaîne de collision. Unpublished Thèse Doct. Etat, University of Montpellier.Google Scholar
Burg, J. P., Leyreloup, A., Giaradeau, J. & Chen, G. M. 1987. Structure and metamorphism of a tectonically thickened continental crust: the Yalu Tsangpo suture zone (Tibet). PHILOS TRANS R SOC LONDON A321, 67–86.Google Scholar
Burnham, C. W. 1967. Hydrothermal fluids at the magmatic stage. In Barnes, H. L. (ed.) Geochemistry of hydrothermal ore deposits, 34–76New York: Holt, Rinehart & Winston.Google Scholar
Castelli, D. & Lombardo, B. 1988. The Gophu La and western Lanana granites: Miocene muscovite leucogranites of the Bhutan Himalaya. LITHOS 21, 211–25.CrossRefGoogle Scholar
Colchen, M., Le, Fort P. & Pêcher, A. 1986. Annapurna-Manaslu-Ganesh Himal, notice de la carte géologique au 1/200.000e Bilingual edition: French-English. Paris: Centre National de la Recherche Scientifique.Google Scholar
Cuney, M., Le, Fort P. & Wang, Z. X. 1984. Uranium and thorium geochemistry and mineralogy in the Manaslu leucogranite (Nepal, Himalaya). In Xu, K. & Tu, G. (eds) Proc. Symp. Geology of granites and Their Metallogenic Relations Nanjing Univ. 1982, 853–73. Beijing: Science Press.Google Scholar
Debon, F., Le, Fort P. & Sonet, J. 1981. Granitoid belts west and south of Tibet. About their geochemical trends and Rb-Sr isotopic studies. In Proc. Symp. on Qinghai-Xizang (Tibet) Plateau, Beijing, 1980, V.1, 395–405. Beijing: Science Press; New York: Gordon & Breach.Google Scholar
Debon, F., Le, Fort P., Sheppard, S. M. F. & Sonet, J. 1986. The four plutonic belts of the Transhimalaya-Himalaya: a chemical, mineralogical, isotopic and chronological synthesis along a Tibet-Nepal section. J PETROL 27, 219–50.CrossRefGoogle Scholar
Debon, F. & Le, Fort P. 1982. A chemical-mineralogical classification of common plutonic rocks and associations. TRANS R SOC EDINBURGH EARTH SCI 73, 135–49.CrossRefGoogle Scholar
Debon, F. & Le, Fort P. 1984. Chemical-mineralogical classification of plutonic rocks and associations—examples from southern Asia belts. In Xu, K. and Tu, G. (eds) Proc. Symp. Geology of granites and Their Metallogenic Relations Nanjing Univ, 1982, 293–311. Beijing: Science Press.Google Scholar
Deniel, C. 1985. Apport des isotopes du Sr, du Nd et du Pb à la connaissance de l'âge et de l'origine des leucogranites himalayens. Exemple du Manaslu (Himalaya, Népal). Unpublished Thèse doct., University of Clermont-Ferrand.Google Scholar
Deniel, C., Vidal, P. & Le, Fort P. 1986. Les leucogranites himalayens et leur région source probable: les gneiss de la “Dalle du Tibet”. C R ACAD SCI PARIS 303, II (1), 57–60.Google Scholar
Deniel, C., Vidal, P., Fernandez, A., Le, Fort P. & Peucat, J. J. 1987. Isotopic study of the Manaslu granite (Himalaya, Nepal): Inferences on the age and source of Himalayan leucogranites. CONTRIB MINERAL PETROL 96, 78–92.CrossRefGoogle Scholar
Dietrich, V. & Gansser, A. 1981. The leucogranites of the Bhutan Himalaya (crustal anatexis versus mantle melting). BULL SUISSE MINERAL PETROG 61, 177–202.Google Scholar
Ferrara, G., Lombardo, B. & Tonarini, S. 1983. Rb/Sr Geochronology of Granites and Gneisses from the Mount Everest Region, Nepal Himalaya. GEOL RUNDSCH 72(1), 119–36.CrossRefGoogle Scholar
France-Lanord, C. 1987. Chevauchement, métamorphisme et magmatisme en Himalaya du Népal Central. Etude isotopique H, C, O. Unpublished Thèse Doct., Institut National Polytechnique de Lorraine.Google Scholar
France-Lanord, C., Sheppard, S. M. F. & Le, Fort P. 1987. C-O-H isotopic evidence for migmation of fluids during the Himalayan reverse metamorphism (abstr.). TERRA COGNITA 7, 136.Google Scholar
France-Lanord, C., Sheppard, S. M. F. & Le, Fort P. 1988. Hydrogen and oxygen isotope variations in the High Himalaya peraluminous Manaslu leucogranite: evidence for heterogeneous sedimentary sources. GEOCHIM COSMOCHIM ACTA 52, 513–526.CrossRefGoogle Scholar
Gansser, A. 1964. Geology of the Himalayas. London: Interscience.Google Scholar
Gariépy, C., Allègre, C. J. & Hua, Xu R. 1985. The Pb-isotope geochemistry from the Himalaya-Tibet Collision zone: implications for crustal evolution. EARTH PLANET SCI LETT 74, 220–34.CrossRefGoogle Scholar
Gilbert, E. 1986. Evolution structurale d'une chaîne de collision: structures et déformation dans le nord de la plaque indienne en Himalaya du Ladakh. (Cristallin du Haut Himalaya et Séries Téthysiennes). Unpublished Thèse, Univ., Poitiers.Google Scholar
Herren, E. 1987. Structures, deformation and metamorphism of the Zanskar area (Ladahk, NW Himalaya). Unpublished Thesis dissertation, ETH Zürich.Google Scholar
Hodges, K. V., Le, Fort P. & Pêcher, A. (submitted). Possible thermal buffering in collisional orogens: thermobarometric evidence from the Nepalese Himalaya. GEOLOGY.Google Scholar
Holtz, F. 1987. Etude structurale, métamorphique et géochimique des granitoides hercyniens et de leur encaissant dans la région de Montalègre. Unpublished Thèse Doctorat, University of Nancy 1.Google Scholar
Jaupart, C. & Provost, A. 1985. Heat focussing, granite genesis and inverted metamorphic gradients in continental collision zones. EARTH PLANET SCI LETT 73, 385–97.CrossRefGoogle Scholar
Kai, K. 1981. Rb-Sr ages of the biotite and muscovite of the Himalayas, eastern Nepal; its implication in the uplift history. GEOCHEM J 15, 63–68.CrossRefGoogle Scholar
Krummenacher, D., Basett, A. M., Kingery, F. A. & Layne, H. F. 1978. Metamorphism and K-Ar age determinations in eastern Nepal. In Saklani, P. S. (ed) Tectonic geology of the Himalaya, 151–66. New Delhi: Today and Tomorrow.Google Scholar
Lapique, F., Champenois, M. & Cheilletz, A. (in press). Un analyseur videographique interactif: DéVeloppement et applications. BULL SOC MIN.Google Scholar
La, Roche H. (de) 1964. Sur l'expression graphique des relations entre la composition chimique et la composition minéralogique quantitative des roches cristallines. Présentation d'un diagramme destiné à l'étude chimico-minéralogique des massifs granitiques ou grano-dioritiques. Application aux Vosges cristallines. SCI DE LA TERRE, Nancy 9, 293–337.Google Scholar
Le, Fort P. 1975. Himalaya: the collided range. Present knowledge of the continental arc. AM J SCI 275A, 1–44.Google Scholar
Le, Fort P. 1981. Manaslu leucogranite: a collision signature of the Himalaya. A model for its genesis and emplacement. J GEOPHYS RES 86, 10545–68.Google Scholar
Le, Fort P. 1986. Metamorphism and magmatism during the Himalayan Collision. In Coward, M. P. & Ries, A. C. (eds) Collision Tectonics. GEOL SOC SPEC PUBL 19, 159–72.Google Scholar
Le, Fort P. 1988. Granites in the tectonic evolution of the Himalaya, Karakorum and southern Tibet. PHILOS TRANS R SOC LONDON (in press).Google Scholar
Le, Fort P. in press. The Himalayan orogenic segment. In Sengör, A. M. C. (ed.) Tectonic evolution of the Tethyan regions, Proceedings of the NATO ASI meeting, Istanbul, October 1985. New York: Reidel.Google Scholar
Le, Fort P., Debon, F., Pêcher, A., Sonet, J. & Vidal, Ph. 1986. The 500 Ma magmatic event in alpine southern Asia, a thermal episode at Gondwana scale. SCI DE LA TERRE, Nancy 47, 191–209.Google Scholar
Le, Fort P., Cuney, M., Deniel, C., France-Lanord, C., Sheppard, S. M. F., Upreti, B. N. & Vidal, P. 1987. Crustal generation of the Himalayan leucogranites. TECTONOPHYSICS 134, 39–57.Google Scholar
Manning, D. A. C. 1981. The effect of fluorine on liqudus phase relationships in the system Qz-Ab-Or with excess water at 1 kabr. CONTRIB MINERAL PETROL 76, 206–15.CrossRefGoogle Scholar
Maruo, Y. & Kizaki, K. 1983. Thermal structure in the nappes of the eastern Nepal Himalayas. In Shams, F. A. (ed.) Granites of Himalaya, Karakorum and Hindu-Kush, 271–86. Lahore: Punjab University.Google Scholar
Molnar, P. 1984. Structure and tectonics of the Himalaya: constraints and implications of Geophysical Data. ANN REV EARTH PLANET SCI 12, 489–518.CrossRefGoogle Scholar
Monier, G. & Robert, J. L. 1986. Evolution of the miscibility gap between muscovite and biotite solid solutions with increasing lithium content: an experimental study in the system K2O-Li2O-MgO-FeO-Al2O3-SiO2-H2O-HF at 600°C, 2 kbar PH2O: comparison with natural lithium micas. MINERAL MAG 50, 641–51.CrossRefGoogle Scholar
Pêcher, A. 1978. Déformation et métamorphisme associés à une zone de cisaillement. Exemple du grand chevauchement central himalayen (M.C.T.), transversales des Annapurnas et du Manaslu, Népal. Unpublished Thèse Doctorat Etat Sci., Grenoble.Google Scholar
Pêcher, A. 1979. Les inclusions fluides des quartz d'exsudation de la zone du M.C.T. himalayen au Népal central: Données sur la phase fluid dans une grande zone de cisaillement crustal. BULL MINERAL 102, 537–54.Google Scholar
Pêcher, A. in press. The metamorphism in Central Himalaya. J MET PETROL.Google Scholar
Pêcher, A. & Bouchez, J. L. 1987. High temperature decoupling between the higher Himalaya crystalline and its sedimentary cover. TERRA COGNITA 7, 2–3, 110.Google Scholar
Pêcher, A. & Le, Fort P. 1986. The metamorphism in Central Himalaya, its relations with the thrust tectonic. In Le, Fort P., Colchen, M. & Montenat, C. (eds) Evolution des domaines orogéniques d'Asie méridionale (de la Turquie à l'Indonésie), 285–309. SCI DE LA TERRE, Nancy, MEM 47.Google Scholar
Pichavant, M. 1983. Approche expérimentale des mécanismes de différenciation dans les systèmes magmatiques riches en silice. Influence des éléments volatils (B. Cl, F). Unpublished These doct. Etat, Institut National Polytechnique de Lorraine.Google Scholar
Pichavant, M. 1984. The effect of boron on liquidus phase relationships in the system Qz-Ab-Or-H2O at 1 kbar. EOS, TRANS AM GEOPHYS UNION 65, 298.Google Scholar
Pichavant, M. 1985. Discussion de l'article “Etude d'une aplo-pegmatite litée à cassitérite et wolframite, magma différencié de l'endogranite de la mine de Santa Comba (Galice, Espagne)” par Y. Gouanvic & C. Gagny 1983. Signification pétrogénétique des pegmatites granitiques. BULL SOC GEOL FRANCE 8,1(2), 269–72.CrossRefGoogle Scholar
Pichavant, M., Valencia Herrera, J., Boulmier, S., Briqueu, L., Joron, J. L., Juteau, M., Marin, L., Michard, A., Sheppard, S. M. F., Treuil, M. & Vernet, M. 1987. The Macusani glasses, SE Peru: evidence of chemical fractionation in per-aluminous magmas. In Mysen, B. O. (ed) Magmatic processes: physicochemical principles, 359–73. GEOCHEM SOC SPEC PUBL 1.Google Scholar
Pichavant, M. & Montel, J. M. 1988. Petrogenesis of a two-mica ignimbrite suite: the Macusani Volcanics, SE Peru. TRANS R SOC EDINBURGH EARTH SCI 79, 197–207.Google Scholar
Pichavant, M. & Ramboz, C. 1985a. Liquidus phase relationships in the system Qz-Ab-Or-B2O3-H2O undersaturated conditions and the effect of H2O on phase relations in the haplogranite system. TERRA COGNITA 5, 230.Google Scholar
Pichavant, M. & Ramboz, C. 1985b. Première détermination expérimentale des relations de phases dans le système haplogranitique en conditions de sous-saturation en H2O. C R ACAD SCI PARIS 301, 11(9), 607–10.Google Scholar
Pinet, C. & Jaupart, C. 1987. A thermal model for the distribution in space and time of the Himalayan granites. EARTH PLANET SCI LETT 84, 87–99.CrossRefGoogle Scholar
Richet, P., Roux, J. & Pineau, F. 1986. Hydrogen isotope fractionation in the system H2O-liquid NaAlSi3O8: new data and comments on D/H fractionation in hydrothermal experiments. EARTH PLANET SCI LETT 78, 115–20.CrossRefGoogle Scholar
Ringwood, A. E. 1974. The petrological evolution of island arc systems. J GEOL SOC LONDON 130, 183–204.CrossRefGoogle Scholar
Sauniac, S. & Touret, J. 1983. Petrology and fluid inclusions of a quartz-kyanite segregation in the main thrust zone of the Himalayas. LITHOS 16, 35–45.CrossRefGoogle Scholar
Scaillet, B., Dardel, J., Le, Fort P. & Pecher, A. 1988. Les leucogranites de Gangotri (Himalaya du Garhwal). Résultats préliminaries (abstract). In 12 ème Réunion des Sciences de la Terre, Lille Avril 1988. SOC GEOL FRANCE.Google Scholar
Schärer, U. 1984. The effect of initial 230Th disequilibrium on young U-Pb ages; the Makalu case, Himalaya. EARTH PLANET SCI LETT 67, 191–204.CrossRefGoogle Scholar
Schärer, U., Xu, R. & Allègre, C. J. 1986. U-(Th)-Pb systematics and age of Himalayan leucogranites, south Tibet. EARTH PLANET SCI LETT 77, 35–48.CrossRefGoogle Scholar
Searle, M. P. & Fryer, B. J. 1986. Garnet, tourmaline and muscovite-bearing leucogranites of the Higher Himalaya from Zanskar, Kulu, Lahoul and Kashmir. In Coward, M. P. & Ries, A. C. (eds) Collision Tectonics, 185–201. GEOL SOC LONDON, SPEC PUBL 19.CrossRefGoogle Scholar
Shand, S. J. 1927. Eruptive rocks. Their genesis, composition, classification and their relation to ore-deposits. London: Murby.Google Scholar
Sheppard, S. M. F. 1986. Igneous rocks: III. isotopic case studies of magmatism in Africa, Eurasia, and Oceanic Islands. Stable Isotopes. In Valley, J. W., Taylor, H. P. Jr. & O'Neil, J. R. (eds) High Temperature Geological Processes, 319–72. MINERAL SOC AM 16.Google Scholar
Taylor, B. E. 1986. Magmatic volatiles: Isotopic variations of C, H, and S. In Valley, J. W., Taylor, H. P. Jr. & O'Neil, J. R. (eds) High Temperature Geological Processes, 185–226. MINERAL SOC AM 16.Google Scholar
Thompson, A. B. 1982. Dehydration melting of pelitic rocks and the generation of H2O-undersaturated granitic liquids. AM J SCI 282, 1567–95.CrossRefGoogle Scholar
Turi, B. & Taylor, H. P. Jr. 1971. An oxygen and hydrogen isotope study of a granodiorite pluton from the Southern California batholith. GEOCHIM COSMOCHIM ACTA 35, 383–406.CrossRefGoogle Scholar
Vidal, Ph., Cocherie, A. & Le, Fort P. 1982. Geochemical investigations of the origin of the Manaslu leucogranite (Himalaya, Nepal). GEOCHIM COSMOCHIM ACTA 46, 2279–92.CrossRefGoogle Scholar
Vidal, Ph., Bernard-Griffiths, J., Cocherie, A., Le, Fort P., Peucat, J. J. & Sheppard, S. M. F. 1984. Geochemical comparison between Himalayan and Hercynian leucogranites. PHYS EARTH PLANET INT 35, 179–90.CrossRefGoogle Scholar
Wones, D. R. & Eugster, H. P. 1965. Stability of biotite: experiment, theory and applications. AM MINER 50, 1228–72.Google Scholar
Wyllie, P. J. 1984. Constraints imposed by experimental petrology on possible and impossible magma sources and products, PHILOS TRANS R SOC LONDON A310, 439–56.Google Scholar