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Garnet pyroxenite and eclogite in the Bohemian Massif: geochemical evidence for Variscan recycling of subducted lithosphere

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Abstract

High-temperature, high-pressure eclogite and garnet pyroxenite occur as lenses in garnet peridotite bodies of the Gföhl nappe in the Bohemian Massif. The high-pressure assemblages formed in the mantle and are important for allowing investigations of mantle compositions and processes. Eclogite is distinguished from garnet pyroxenite on the basis of elemental composition, with mg number <80, Na2O > 0.75 wt.%, Cr2O3 < 0.15 wt.% and Ni < 400 ppm. Considerable scatter in two-element variation diagrams and the common modal layering of some eclogite bodies indicate the importance of crystal accumulation in eclogite and garnet pyroxenite petrogenesis. A wide range in isotopic composition of clinopyroxene separates [εNd, +5.4 to −6.0; (87Sr/86Sr)i, 0.70314–0.71445; δ18OSMOW, 3.8–5.8%o] requires that subducted oceanic crust is a component in some melts from which eclogite and garnet pyroxenite crystallized. Variscan Sm-Nd ages were obtained for garnet-clinopyroxene pairs from Dobešovice eclogite (338 Ma), Úhrov eclogite (344 Ma) and Nové Dvory garnet pyroxenite (343 Ma). Gföhl eclogite and garnet pyroxenite formed by high-pressure crystal accumulation (±trapped melt) from transient melts in the lithosphere, and the source of such melts was subducted, hydrothermally altered oceanic crust, including subducted sediments. Much of the chemical variation in the eclogites can be explained by simple fractional crystallization, whereas variation in the pyroxenites indicates fractional crystallization accompanied by some assimilation of the peridotite host.

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References

  • Aftalion M, Bowes DR, Vrána S (1989) Early Carboniferous U-Pb zircon age for garnetiferous, perpotassic granulites, Blanský les massif, Czechoslovakia. N Jahrb Mineral Mh 4:145–152

    Google Scholar 

  • Bakun-Czubarow N (1991) Geodynamic significance of the Variscan HP eclogite-granulite series of the Zlote Mountains in the Sudetes. Publ Inst Geophys Pol Acad Sci 236:215–244

    Google Scholar 

  • Beard BL (1992) Geochemistry, geochronology, and petrogenesis of eclogite and garnet peridotite from the Bohemian Massif, Czechoslovakia, and Hf isotope characteristics of basaltic rocks from the Rio Grande Rift region, southwestern United States. PhD Thesis, Univ Wisconsin, Madison, 262 pp

    Google Scholar 

  • Beard BL, Medaris LG Jr, Johnson CM, Brueckner HK, Mísař Z (1992) Petrogenesis of Variscan high-temperature Group A eclogites from the Moldanubian Zone of the Bohemian Massif, Czechoslovakia. Contrib Mineral Petrol 111:468–483

    Google Scholar 

  • Beard BL, Medaris LG Jr, Johnson CM, Jelínek E, Tonika J, Riciputi LR. Geochronology and geochemistry of eclogites from the Mariánské Lázně Complex, Czech Republic. Implications for Variscan orogenesis. Geol Rundsch, in press

  • Behr H-J, Engel W, Franke W, Giese P, Weber K (1984) The Variscan belt in Central Europe. Main structures, geodynamic implications, open questions. Tectonophysics 109:15–40

    Google Scholar 

  • Brueckner HK, Medaris LG Jr, Bakun-Czubarow N (1991) Nd and Sr age and isotope patterns from Variscan eclogites of the eastern Bohemian Massif. N Jahrb Mineral Abh 163:169–196

    Google Scholar 

  • Burke WH, Denison RE, Hetherington EA, Koepnick RB, Nelson HF, Otto JB (1982) Variation of seawater 87Sr/86Sr through Phanerozoic time. Geology 10:516–519

    Google Scholar 

  • Carswell DA (1990) Eclogites and the eclogite facies. Definitions and classifications. In: Carswell DA (ed) Eclogite Facies Rocks. Blackie, Glasgow, pp 1–13

    Google Scholar 

  • Carswell DA (1991) Variscan high P-T metamorphism and uplift history in the Moldanubian Zone of the Bohemian Massif in Lower Austria. Eur J Mineral 3:323–342

    Google Scholar 

  • Carswell DA, Jamtveit B (1990) Variscan Sm-Nd ages for the high-pressure metamorphism in the Moldanubian Zone of the Bohemian Massif, Lower Austria. N Jahrb Mineral Abh 162:69–78

    Google Scholar 

  • Carswell DA, O'Brien PJ (1993) Thermobarometry and geotectonic significance of high-pressure granulites. Examples from the Moldanubian Zone of the Bohemian Massif in Lower Austria. J Petrol 34:427–459

    Google Scholar 

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

    Google Scholar 

  • Dickey JS Jr (1970) Partial fusion products in alpine-type peridotites. Serrania de la Ronda and other examples. Spec Pap Mineral Soc Am 3:33–49

    Google Scholar 

  • Dosso L, Murthy VR (1980) A Nd isotopic study of the Kerguelen Islands: inferences on enriched oceanic mantle sources. Earth Planet Sci Lett 48:268–276

    Google Scholar 

  • Fiala J, Paděra K (1977) The chemistry of the minerals of the pyrope dunite from borehole T-7 near Staré (Bohemia). Tschermaks Mineral Petrol Mitt 24:205–219

    Google Scholar 

  • Franke W (1989) Tectonostratigraphic units in the Variscan belt of central Europe. Spec Pap Geol Soc Am 230:67–90

    Google Scholar 

  • Frey FA, Green DH, Roy SD (1978) Integrated models of basalt petrogenesis. A study of quartz tholeiites to olivine melilitites from South Eastern Australia utilizing geochemical and experimental petrological data. J Petrol 19:463–513

    Google Scholar 

  • Fusán O, Kodym O, Matějka A, Urbánek L (1967) Geologická Mapa CSSR, 1:500,000. Ústrednf Ústav Geologický, Prague

    Google Scholar 

  • Gebauer D, Grünenfelder M (1979) U-Pb zircon and Rb-Sr mineral dating of eclogites and their country rocks. Example. Münchberg Gneiss Massif, northeast Bavaria. Earth Planet Sci Lett 42:35–44

    Google Scholar 

  • Griffin WL (1987) On the eclogites of Norway. 65 years later. Mineral Mag 51:333–343

    Google Scholar 

  • Hart SR (1988) Heterogeneous mantle domains. Signatures, genesis and mixing chronologies. Earth Planet Sci Lett 90:272–296

    Google Scholar 

  • Hawkesworth CJ, Norry MJ, Roddick JC, Vollmer R (1979) 143Nd/144Nd and 87Sr/86Sr ratios from the Azores and their significance in LIl-element enriched mantle. Nature 280:28–31

    Google Scholar 

  • Hofmann AW (1988) Chemical differentiation of the Earth: the relationship between mantle, continental crust, and oceanic crust. Earth Planet Sci Lett 90:297–314

    Google Scholar 

  • Jaques AL, Green DH (1980) Anhydrous melting of peridotite at 0–15 kbar pressure and the genesis of tholeiitic basalts. Contrib Mineral Petrol 73:287–310

    Google Scholar 

  • Kastl E, Tonika J (1984) The Mariánské Lázně metaophiolite complex (West Bohemia). Krystalinikum 17:59–76

    Google Scholar 

  • Kohn MJ, Valley JW, Elsenheimer D, Spicuzza MJ (1993) O isotope zoning in garnet and staurolite. Evidence for closed system mineral growth during regional metamorphism. Am Mineral 78:988–1001

    Google Scholar 

  • Kornprobst J, Piboule M, Tabit A (1987) Diversité des clinopyroxénites à grenat associées aus massifs ultramafiques orogéniques. Éclogites, ariégites, griquaites et grospydites. Une discussion. Bull Soc géol Fr 8:345–351

    Google Scholar 

  • Korotev R (1987) National Bureau of Standards coal flyash (SRM1633a) as a multielement standard for instrumental neutron activation analysis. J Radioanal Nucl Chem 110:159–177

    Google Scholar 

  • Kröner A, Wendt I, Liew TC, Compston W, Todt W, Fiala J, Vanek J (1988) U-Pb zircon and Sm-Nd model ages of highgrade Moldanubian metasediments, Bohemian Massif, Czechoslovakia. Contrib Mineral Petrol 99:257–266

    Google Scholar 

  • Kyser TK (1990) Stable isotopes in the continental lithospheric mantle. In: Menzies MA (ed) Continental Mantle. Clarendon, Oxford, pp 127–156

    Google Scholar 

  • Lorenz V, Nicholls IA (1984) Plate and intraplate processes of Hercynian Europe during the Late Paleozoic. Tectonophysics 107:25–56

    Google Scholar 

  • Machart J (1984) Ultramafic rocks in the Bohemian part of the Moldanubicum and central Bohemian islet zone (Bohemian massif). Krystalinikum 17:13–32

    Google Scholar 

  • Machart J (1988) Petrology and position of ultramafic rocks in the Moldanubian region of the Bohemian Massif. In: Zoubek V, Cogné J, Kozhoukharov D, Kräutner HG (eds) Precambrian in Younger Fold Belts. Wiley, New York, pp 233–238

    Google Scholar 

  • Matte P (1991) Accretionary history and crustal evolution of the Variscan belt in Western Europe. Tectonophysics 196:309–337

    Google Scholar 

  • Matte P, Maluski H, Rajlich P, Franke W (1990) Terrane boundaries in the Bohemian Massif. Result of large-scale Variscan shearing. Tectonophysics 177:151–170

    Google Scholar 

  • Mattey D, Lowey D, Macpherson C (1993) Oxygen isotope composition of mantle olivine. Terra Nova 5, Abstr Suppl 1:375

    Google Scholar 

  • Medaris LG Jr, Carswell DA (1990) The petrogenesis of Mg-Cr garnet peridotites in European metamorphic belts. In: Carswell DA (ed) Eclogite Facies Rocks. Blackic, Glasgow, pp 260–290

    Google Scholar 

  • Medaris LG Jr, Wang HF, Mísař Z, Jelínek E (1990) Thermobarometry, diffusion modelling and cooling rates of crustal garnet peridotites. Two examples from the Moldanubian zone of the Bohemian Massif. Lithos 25:189–202

    Google Scholar 

  • Medaris LG Jr, Jelínek E, Mísař Z (1995) Czech eclogites. Terrane settings and implications for Variscan tectonic evolution of the Bohemian Massif. Eur J Mineral 7:7–28

    Google Scholar 

  • Meissner R, Tanner B (1993) From collision to collapse. Phases of lithospheric evolution as monitored by seismic records. Phys Earth Planet Interiors 79:75–86

    Google Scholar 

  • Miller DM, Langmuir CH, Goldstein SL, Franks AL (1992) The importance of parental magma composition to calc-alkaline and tholeiitic evolution. Evidence from Umnak Island in the Aleutians. J Geophys Res 97:321–343

    Google Scholar 

  • Mísař Z, Dudek A, Havlena V, Weiss J (1983) Geologie CSSR 1. Český Masív. Státní Pedagogické Nakladatelství, Prague, 333 pp

    Google Scholar 

  • Muehlenbachs K (1986) Alteration of the oceanic crust and the 18O history of seawater. In: Valley JW, Taylor HP, O'Neil JR (eds) Stable Isotopes in High Temperature Geological Processes. Rev Mineral 16: Mineral Soc Am, 425–444

  • O'Nions RK, Hamilton PJ, Evensen NM (1977) Variations in 143Nd/144Nd and 87Sr/86Sr ratios in oceanic basalts. Earth Planet Sci Lett 34:13–22

    Google Scholar 

  • Othman DB, White WM, Patchett J (1989) The geochemistry of marine sediments, island arc magma genesis, and crust-mantle recycling. Earth Planet Sci Lett 94:1–21

    Google Scholar 

  • Ottonello G, Ernst WG, Joron JL (1984) Rare earth and 3d transition element geochemistry of peridotitic rocks I. Peridotites from the western Alps. J Petrol 25:343–372

    Google Scholar 

  • Paris F, Robardet M (1990) Early Paleozoic palaeobiogeography of the Variscan regions. Tectonophysics 177:193–213

    Google Scholar 

  • Pearson DG, Davies GR, Nixon PH, Greenwood PB, Mattey DP (1991) Oxygen isotope evidence for the origin of pyroxenites in the Beni Bousera peridotite massif, N. Morocco. Derivation from subducted oceanic lithosphere. Earth Planet Sci Lett 102:289–301

    Google Scholar 

  • Pearson DG, Davies GR, Nixon PH (1993) Geochemical constraints on the petrogenesis of diamond facies pyoxenites from the Beni Bousera peridotite massif, North Morocco. J Petrol 34:125–172

    Google Scholar 

  • Rost F (1961) Zur Stellung der Granatultrabasite des Sächsischen Grundgebirges. Freiberger Forsch, Geol 119:121–134

    Google Scholar 

  • Scharbert HG, Carswell DA (1983) Petrology of garnet-clinopyroxene rocks in a granulite facies environment, Bohemian massif of Lower Austria. Bull Mineral 106:761–774

    Google Scholar 

  • Shervais JW, Mukasa SB (1991) The Balmuccia orogenic lherzolite massif, Italy. J Petrol Spec Lherzolites Issue: 155–174

  • Stosch H-G, Lugmair GW (1990) Geochemistry and evolution of MORB-type eclogites from the Münchberg Massif, southern Germany. Earth Planet Sci Lett 99:230–249

    Google Scholar 

  • Suen CJ, Frey FA (1987) Origins of the mafic and ultramafic rocks in the Ronda peridotite. Earth Planet Sci Lett 85:183–202

    Google Scholar 

  • Sun SS, McDonough WF (1989) Chemical and isotopic systematics of oceanic basalts. Implications for mantle composition and processes. In: Saunders AD, Norry MJ (eds) Magmatism in the Ocean Basins. Spec Publ Geol Soc London 42:313–345

    Google Scholar 

  • Synek J, Oliveriová D (1993) Terrane character of the north-east margin of the Moldanubian Zone. The Kutná Hora Crystalline Complex, Bohemian Massif. Geol Rundsch 82:566–582

    Google Scholar 

  • Tollmann A (1982) Gossräumiger variszischer Deckenbau im Moldanubikum und neue Gedanken zum Variszikum Europas. Geotekton Forsch 64:1–91

    Google Scholar 

  • van Breemen O, Aftalion M, Bowes DR, Dudek A, Mísař Z, Povondra P, Vrána S (1982) Geochronological studies of the Bohemian Massif, Czechoslovakia, and their significance in the evolution of central Europe. Trans Roy Soc Edinburgh 75:89–108

    Google Scholar 

  • von Quadt A, Gebauer D (1993) Sm-Nd and U-Pb dating of eclogites and granulites from the Oberpfalz, NE Bavaria, Germany. Chem Geol 109:317–339

    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 

  • White WM, Hofmann AW (1982) Sr and Nd isotope geochemistry of oceanic basalts and mantle evolution. Nature 296:821–825

    Google Scholar 

  • Wilshire HG, Shervais JW (1975) Al-augite and Cr-diopside ultramafic xenoliths in basaltic rocks from the western United States. Phys Chem Earth 9:257–272

    Google Scholar 

  • Ziegler PA (1986) Geodynamic model for the Palaeozoic crustal consolidation of western and central Europe. Tectonophysics 126:303–328

    Google Scholar 

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Medaris, L.G., Beard, B.L., Johnson, C.M. et al. Garnet pyroxenite and eclogite in the Bohemian Massif: geochemical evidence for Variscan recycling of subducted lithosphere. Geol Rundsch 84, 489–505 (1995). https://doi.org/10.1007/BF00284516

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