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Nd-, Sr-, O-isotopic and chemical evidence for a two-stage contamination history of mantle magma in the Central-Alpine Bergell intrusion

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Abstract

Two different contamination processes have been identified as having been operative in the genesis of a plutonic suite: initial contamination of a mantle source, and subsequent crustal contamination of uprising partial melts from the mantle. These processes are indicated by a detailed analyses of Nd, Sr, and oxygen isotopes together with major-and trace-elements of the 32–30 Ma calc-alkaline Bergell intrusion. This intrusion is located at the suture of the Alpine continental collision zone and contains rock types capable of discriminating between mantle and intracrustal processes. A range from basaltic-andesitic dykes in the surrounding country rocks, cumulitic hornblendites, gabbros, tonalite, granodiorite and lamprophyres, to pegmatites and aplites, is exposed in this single intrusion. The results of REE modelling and isotopic compositions of the basic members suggest that the cumulates were fractionated from a picrobasaltic liquid originating by partial melting of enriched subcontinental mantle (εNd=+4). Increases in 87Sr/86Sr (0.7055) and δ18O(+6.7) in these samples relative to the mantle array and compositions of other Periadriatic intrusions are most likely the result of an initial contamination of the mantle source by dehydration or partial melting of altered subducted oceanic crust. Slight differentiation of such a picrobasaltic liquid produced the basaltic-andesitic dykes. Simultaneous fractional crystallization and contamination of the uprising magma by continental crust produced crustal isotopic signatures which increase with acidity to values of (εNd=-7.6), 87Sr/86Sr=0.716 and δ18O=+10. The crustal imprint and LREE enrichment in the dominating tonalite increase with decreasing crystallization depth which indicates that the tonalites were emplaced in several distinct batches with different degrees of contamination. Shoshonitic lamprophyres, which intruded into the partly solidified granodiorite, were generated in a deep, strongly contaminated mantle source. The posttectonic 26 Ma Novate leucogranite is not cogenetic with the main Bergell body, but rather formed from a predominantly crustal source. If the described features are indeed due to mantle source contamination processes, which are well known for volcanic arcs, it must be concluded that these may also play a significant role in the genesis of calcalkaline plutonic suites.

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References

  • Arth JG, Barker F (1976) Rare-earth partitioning between hornblende and dacitic liquid and implications for the genesis of trondhjemitic-tonalitic magmas. Geology 4:534–536

    Google Scholar 

  • Barth S, Oberli F, Meier M (1989) U-Th-Pb systematics of morphologically characterized zircon and allanite: a high-resolution isotopic study of the Alpine Rensen pluton (northern Italy). Earth Planet Sci Lett 95:235–254

    Google Scholar 

  • Bernoulli D, Heitzmann P, Zingg A (1990) Central and southern Alps in southern Switzerland: tectonic evolution and first results of reflection seismics. In: Roure F, Heitzmann P, Polino R (eds) Deep structure of the Alps. Mém Soc géol France 156; Mém Soc géol suisse 1; Geol Soc Ital, Vol spec 1: 289–302

  • von Blanckenburg F (1990) Isotope geochemical and geochronological case studies of Alpine magmatism and metamorphism: the Bergell intrusion and Tauern Window. PhD dissertation ETH Zürich

  • Chen C-H, Shieh Y-N, Lee T, Chen C-H, Mertzman SA (1990) Nd-Sr-O isotopic evidence for source contamination and an unusual mantle component under Luzon Arc. Geochim Cosmochim Acta 54:2473–2483

    Google Scholar 

  • Clondiffe E, Mottana A (1974) Studio sperimentale del «serizzo» a moderate pressioni. Soc It Mineral e Petrol 30:919–930

    Google Scholar 

  • Davidson JP, Harmon RS (1989) Oxygen isotope constraints on the petrogenesis of volcanic arc magmas from Martinique, Lesser Antilles. Earth Planet Sci Lett 95:255–270

    Google Scholar 

  • DePaolo DJ (1981) Trace element and isotopic effects of combined wallrock assimilation and fractional crystallization. Earth Planet Sci Letters 53:189–202

    Google Scholar 

  • DePaolo DJ (1988) Neodymium isotope geochemistry. Springer, Berlin Heidelberg New York

    Google Scholar 

  • Dickin AP, Exley RA, Smith BM (1980) Isotopic measurement of Sr and O exchange between metoric-hydrothermal fluid and the Coire Uaigneich granophyre, Isle of Skye, N.W. Scotland. Earth Planet Sci Lett 51:58–70

    Google Scholar 

  • Diethelm K (1985) Hornblendite und Gabbros im östlichen Bergell (Val Sissone, Provinz Sondrio, Italien). Schweiz Mineral Petrogr Mitt 65:223–246

    Google Scholar 

  • Diethelm K (1989) Petrographische und geochemische Untersuchungen an basischen Gesteinen der Bergeller Intrusion. PhD dissertation ETH-Zürich

  • Drescher-Kaden FK (1940) Beiträge zur Kenntnis der Migmatit-und Assimilationsbildungen, sowie der synantetischen Reaktionsformen. I. Über Schollenassimilation und Kristallisationsverlauf im Bergeller Granit. Chem Erde 12:157–238

    Google Scholar 

  • Elderfield H, Hawkesworth CJ, Greaves MJ, Calvert SE (1981) Rare earth element geochemistry of oceanic ferromanganese nodules and associated sediments. Geochim Cosmochim Acta 45:513–528

    Google Scholar 

  • England PC, Thompson AB (1986) Some thermal and tectonic models for crustal melting in continental collision zones. In: Coward MP, Ries AC (eds) Collision tectonics. Geol Soc London Spec Pub 19:83–94

  • Faure G (1986) Principles of isotope geology, 2nd edn. John Wiley & Sons, New York

    Google Scholar 

  • Fowler MB, Harmon RS (1990) The oxygen isotope composition of lower crustal granulite xenoliths. In: Vielzeuf D, Vidal P (eds) Granulites and crustal evolution. Kluwer Academic Publishers, Dordrecht, pp 493–506

    Google Scholar 

  • Gautschi A, Montrasio A (1978) Die andesitisch-basaltischen Gänge des Bergeller Ostrandes und ihre Beziehung zur Regional-und Kontaktmetamorphose. Schweiz Mineral Petrogr Mitt 58:329–343

    Google Scholar 

  • Gulson BL (1973) Age relations in the Bergell region of the southeast Swiss Alps: with some geochemical comparisons. Eclogae Geol Helv 66:293–313

    Google Scholar 

  • Gulson BL, Krogh TE (1973) Old lead components in the young Bergell massif, south-east Swiss Alps. Contrib Mineral Petrol 40:239–252

    Google Scholar 

  • Halliday AN (1983) Crustal melting and the genesis of isotopically and chemically zoned plutons in the Southern Uplands of Scotland. In: Atherton MP, Gribble CD (eds) Migmatites, melting and metamorphism. Shiva publ ltd, Nautwich, pp 54–61

    Google Scholar 

  • Hawkesworth CJ, O'Nions RK, Pankhurst PJ, Hamilton PJ, Evenson NM (1977) A geochemical study of island-arc and back-arc tholeiites from the Scotia Sea. Earth Planet Sci Lett 36:253–262

    Google Scholar 

  • Henderson P (1982) Inorganic geochemistry. Pergamon, Oxford

    Google Scholar 

  • Hill RI, Silver LT, Taylor HP (1986) Coupled Sr−O isotope variations as indicator of source heterogeneity for the Northern Peninsular Ranges batholith. Contrib Mineral Petrol 92:351–361

    Google Scholar 

  • Hoernes S, Friedrichsen H (1980) Oxygen and hydrogen isotopic composition of Alpine and pre-Alpine minerals of the Swiss Central Alps. Contrib Mineral Petrol 72:19–32

    Google Scholar 

  • James DE (1981) The combined use of oxygen and radiogenic isotopes as indicators of crustal contamination. Ann Rev Earth Planet Sci 9:311–344

    Google Scholar 

  • Juteau M, Michard A, Albarede F (1986) The Pb−Sr−Nd isotope geochemistry of some recent circum-Mediterranean granites. Contrib Mineral Petrol 92:331–340

    Google Scholar 

  • Kagami H, Fischer H, Steiger RH (1985) Nd and Sr isotope evidence for the crustal origin of the Periadriatic plutons (abstr). Terra Cognita 5:324

    Google Scholar 

  • Kagami H, Ulmer P, Hansmann W, Dietrich V, Steiger RH (1991) Nd−Sr isotopic and geochemical characteristics of the southern Adamello (N Italy) intrusives: implications for crustal versus mantle origin. J Geoph Res 96:B14331–14346

    Google Scholar 

  • Köppel V, Grünenfelder M (1975) Concordant U−Pb ages of monazite and xenotime from the Central Alps and the timing of the high temperature Alpine metamorphism, a preliminary report. Schweiz Mineral Petrogr Mitt 55:129–132

    Google Scholar 

  • Krogh TE (1973) A low-contamination method for hydrothermal decomposition of zircon and extraction of U and Pb for isotopic age determinations. Geochim Cosmochim Acta 37:485–494

    Google Scholar 

  • Kyser TK (1990) Stable isotopes in the continental lithospheric mantle. In: Menzies MA (ed) Continental Mantle. Clarendon Press, Oxford

    Google Scholar 

  • Liew TC, Hoffmann 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 

  • Mottana A, Morten L, Brunfelt AO (1978) Distribuzionc delle terre rare nel massiccio Val Masino-Val Bregaglia (Alpi Centrali). Rend Soc Ital Mineral Petrol 34:485–497

    Google Scholar 

  • Nievergelt P, Dietrich V (1977) Die andesitisch-basaltischen Gänge des Piz Lizun (Bergell). Schweiz Mineral Petrogr Mitt 57:267–280

    Google Scholar 

  • Reusser E (1987) Phasenbeziehungen im Tonalit der Bergeller Intrusion (Graubünden, Schweiz/Provinz Sondrio, Italien). PhD Dissertation, ETH-Zürich

  • Staub R (1918) Geologische Beobachtungen am Bergeller massiv. Vierteljahrssch Naturforsch Ges Zürich 63:1–18

    Google Scholar 

  • Staub R (1921) Geologische Karte der Val Bregaglia (Bergell). Geologische Spezialkarten der Schweiz, Blatt 90

  • Stern CR, Frey FA, Futa K, Zartman RE, Peng Z, Kyser TK (1990) Trace-element and Sr, Nd, Pb, and O isotopic composition of Pliocene and Quarternary alkali basalts of the Patagonian Plateau lavas of southernmost South America. Contrib Mineral Petrol 104:294–308

    Google Scholar 

  • Stille P (1987) Geochemische Aspekte der Krustenevolution im zentral-und südalpinen Raum. Habilitationsschrift, ETH Zürich

  • Stille P, Buletti M (1987) Nd−Sr isotopic characteristics of the Lugano volcanic rocks and constraints on the continental crust formation in the South Alpine domain (N-Italy-Switzerland). Contrib Mineral Petrol 96:140–150

    Google Scholar 

  • Stille P, Fischer H (1990) Secular variation in the isotopic composition of Nd in Tethys seawater. Geochim Cosmochim Acta 54:3139–3145

    Google Scholar 

  • Stille P, Steiger RH (1991) Hf isotope systematics in granitoids from the central and southern Alps. Contrib Mineral Petrol 107:273–278

    Google Scholar 

  • Stille P, Oberhänsli R, Wenger-Schenk K (1989) Hf−Nd isotopic and trace element constraints on the genesis of alkaline and calc-alkaline lamprophyres. Earth Planet Sci Lett 96:209–219

    Google Scholar 

  • Taylor HP Jr (1980) The effects of assimilation of country rocks by magmas on 18O/16O and 87Sr/86Sr systematics in igneous rocks. Earth Planet Sci Lett 47:243–254

    Google Scholar 

  • Tilton GR, Schreyer W, Schertl H-P (1989) Pb−Sr−Nd isotopic behavior of deeply subducted crustal rocks from the Dora Maira Massif, Western Alps, Italy. Geochim Cosmochim Acta 53:1391–1400

    Google Scholar 

  • Trommsdorff V, Nievergelt P (1983) The Bregaglia (Bergell) Iorio intrusive and its field relations. Mem Soc Geol Italy 26:55–68

    Google Scholar 

  • Turpin L, Velde D, Pinte G (1988) Geochemical comparison between minettes and kersantites from the Western European Hercynian orogen: trace element and Pb−Sr−Nd isotope constraints on their origin. Earth Planet Sci Lett 87:73–86

    Google Scholar 

  • Ulmer P (1988) High pressure phase equilibria of a calc-alkaline picro-basalt: Implications for the genesis of calc-alkaline magmas. Carnegie Inst Washington, Ann Rep of the Dir Geoph Lab 2102:28–35

    Google Scholar 

  • Ulmer P, Callegari E, Sonderegger UC (1983) Genesis of the mafic and ultramafic rocks and their genetical relations to the tonalitic-trondhjemitic granitoids of the southern part of the Adamello batholith (Northern Italy). Mem Soc Geol Ital 26:171–222

    Google Scholar 

  • Voshage H, Hofmann AW, Mazzucchelli M, Rivalenti G, Sinigoi S, Raczek I, Demarchi G (1990) Isotopic evidence from the Ivrca Zone for a hybrid lower crust formed by magmatic underplating. Nature 347:731–736

    Google Scholar 

  • Wasserburg GJ, Jacobsen SB, DePaolo DJ, McCulloch MT, Wen T (1981) Precise determination of Sm/Nd ratios, Sm and Nd isotopic abundances in standard solutions. Geochim Cosmochim Acta 45:2311–2323

    Google Scholar 

  • Weber J (1957) Petrographische und geologische Untersuchung des Tonalitzuges von Melirolo-Sorico zwischen Tessintal und Comersee. Schweiz Mineral Petrogr Mitt 37:267–397

    Google Scholar 

  • Wedepohl KH (1978) Handbook of geochemistry, vol 2/4. Springer, Berlin Heidelberg New York

    Google Scholar 

  • Wenk HR (1982) A geological history of Bergell granite and related rocks. In: Drescher-Kaden FK, Augustithis SS (eds) Transformists' Petrology. Theophrastus Publications, Athens, pp 113–148

    Google Scholar 

  • Wenk HR, Cornelius SB (1977) Geologischer Atlas der Schweiz 1:25000, Blatt 70, Sciora, Schweiz Geol Komm

  • Wyllie PJ, Wuu-Liang Huang, Stern CR, Maaløe S (1976) Granitic magmas: possible and impossible sources, water contents, and crystallization sequences. Can J Earth Sci 13:1007–1019

    Google Scholar 

  • Wilson M, Downes H (1991) Tertiary-Quaternary extension-related alkaline magmatism in Western and Central Europe. J Petrol 32:811–849

    Google Scholar 

  • Ych H (1980) D/H ratios and late-stage dehydration of shales during burial. Geochim Cosmochim Acta 44:341–352

    Google Scholar 

Download references

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Author notes

  1. Friedhelm von Blanckenburg

    Present address: Department of Earth Sciences, University of Cambridge, Downing Street, CB2 3EQ, Cambridge, UK

  2. Peter Stille

    Present address: Centre de Geochimie de la Surface, C.N.R.S., 1, rue Blessig, F-67000, Strasbourg-Cedex, France

Authors and Affiliations

  1. Institut für Kristallographie und Petrographie, ETH-Zentrum, CH-8092, Zürich, Switzerland

    Friedhelm von Blanckenburg & Peter Stille

  2. Institut für Mineralogie und Petrographie, ETH-Zentrum, CH-8092, Zürich, Switzerland

    Gretchen Früh-Green & Karlheinz Diethelm

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von Blanckenburg, F., Früh-Green, G., Diethelm, K. et al. Nd-, Sr-, O-isotopic and chemical evidence for a two-stage contamination history of mantle magma in the Central-Alpine Bergell intrusion. Contr. Mineral. and Petrol. 110, 33–45 (1992). https://doi.org/10.1007/BF00310880

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