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Eclogite relics in the Variscan orogenic belt of Bulgaria (SE Europe)

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Abstract

Eclogitic rocks were sampled from two zones in the basement of the Sredna Gora terrane (central western Bulgaria): (1) partially retrogressed eclogites and amphibolites embedded in sillimanite-bearing garnet-micaschists with kyanite relics and migmatites and (2) banded amphibolites associated with muscovite-bearing metagranites within two-mica paragneisses. Rutile relics and oligoclase + green hornblende + epidote ± biotite pseudomorphs after garnet suggest an eclogite facies event. A tholeiitic, transitional affinity was determined for the protoliths, suggesting a continental rift environment, consistent with several eclogite-bearing complexes in the eastern segments of the Variscan belt that arose from the Cambro-Ordovician Gondwana break-up. Decreasing pressure after the eclogite overprint was demonstrated by (a) diopside-albite symplectite, and (b) plagioclase + red–brown to green amphibole kelyphite. The early static re-equilibration, dated to 398 ± 5.2 Ma by 40Ar–39Ar technique, was followed by an amphibolite facies foliation, which was pervasive in amphibolites, gneisses and micaschists, and poorly developed in eclogites. The lithospheric PT paths corresponding to higher and lower metamorphic gradients reflect the juxtaposition of crustal and lithospheric mantle units, respectively. In the build-up of the basement of the Balkan orogen, the physical properties of the lithological complexes might have influenced the collisional pattern of involved microplates.

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References

  • Arnaudov V, Amov B, Bartnitskii E, Pavlova M (1989) Isotope geochronology of igneous and metamorphic rocks from the Balkan range and the Rhodope massive. Extended abstracts XIV Congress CBGA, Sofia, vol 4, pp 1154–1157

  • Beard BL, Medaris LG Jr, Johnson CM, Jelínek E, Tonika J, Riciputi LR (1995) Geochronology and geochemistry of eclogites from the Mariánské Láme Complex, Czech Republic: implications for Variscan orogenesis. Geol Rundsch 84:552–567

    Article  Google Scholar 

  • Bertrand JM, Pidgeon RT, Leterrier J, Guillot F, Gasquet D, Gattiglio M (2000) SHRIMP and IDTIMS U–Pb zircon ages of the pre-Alpine basement in the Internal Western Alps (Savoy and Piedmont). Schweiz Mineral Petrogr Mitt 80:225–248

    Google Scholar 

  • Briand B, Bouchardon JL, Ouali H, Piboule M, Capiez P (1995) Geochemistry of bimodal amphibolite-felsic gneiss complexes from eastern Massif Central, France. Geol Mag 132:321–337

    Article  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. Neues Jahrb MineraI Abh 163:169–196

    Google Scholar 

  • Cabanis B, Thieblemont D (1988) La discrimination des tholeiites continentales et des basaltes arrière-arc–Proposition d’un nouveau diagramme, le triangle Th-Tbx3-Tax2. Bull Soc Geol France 4:927–935

    Google Scholar 

  • Capelli C, Cortesogno L, Gaggero L (1994) Metabasites and associated ultramafites in the crystalline basement of Ligurian Alps; petrochemical characterization and geotectonic significance. Per Mineral 63:179–219

    Google Scholar 

  • Carrigan CW, Mukasa SB, Haydoutov I, Kolcheva K (2003) Ion microprobe U-Pb zircon ages of pre-Alpine rocks in the Balkan, Sredna Gora and Rhodope terranes of Bulgaria: constraints on Neoproterozoic and Variscan tectonic evolution. J Czech Geol Soc 48:32–33

    Google Scholar 

  • Carrigan CW, Mukasa SB, Haydoutov I, Kolcheva K (2006) Neoproterozoic magmatism and Carboniferous high-grade metamorphism in the Sredna Gora Zone, Bulgaria: an extension of the Gondwana-derived Avalonian–Cadomian belt? Precambrian Res 147:404–416

    Article  Google Scholar 

  • Chopin C (1985) Les relations de phase dans les métapelites de haute pression. Approche expérimentale et naturaliste. Conséquences géodynamiques pour les Alpes Occidentales. Thèse d’Etat, Univ Paris VI, pp 180

  • Cortesogno L, Gaggero L, Oggiano G, Paquette JL (2004) Different tectono-thermal evolutionary path in eclogitic rocks from the axial zone of the Variscan Chain in Sardinia (Italy) compared with the Ligurian Alps. Ofioliti 29:125–144

    Google Scholar 

  • Dahl PS (1996) The effects of composition on retentivity of argon and oxygen in hornblende and related amphiboles: a field-tested empirical model. Geochim Cosmochim Acta 60:3687–3700

    Article  Google Scholar 

  • Deer WA, Howie RA, Zussman J (1997) Double-chain silicates. The Geological Society (ed), The Geological Society Publishing House, London, vol 2B, p 240

  • Dimitrova E, Belmustakova H (1982a) Eclogite relicts in the Sredna Gora crystalline schists complex. Geol Balc 12:115–120

    Google Scholar 

  • Dimitrova E, Belmustakova H (1982b) Metamorphic facies of the crystalline schists of Ihtiman Sredna Gora Mountain. Geochim Mineral Petrol 16:61–67

    Google Scholar 

  • Di Vincenzo G, Palmeri R (2001) An Ar–Ar investigation of high-pressure metamorphism and the retrogressive history of mafic eclogites from the Lanterman Range (Antarctica): evidence against a simple temperature control on argon transport in amphibole. Contrib Mineral Petrol 141:15–35

    Google Scholar 

  • Essene EJ, Fyfe WS (1967) Omphacite in Californian metamorphic rocks. Contrib Mineral Petrol 15:1–23

    Article  Google Scholar 

  • Frey M, De Capitani C, Liou JG (1991) A new petrogenetic grid for low grade metabasites. J Metam Geol 9:497–509

    Article  Google Scholar 

  • Fumagalli P, Poli S (2004) Modelling metamorphic rocks in complex systems: present-day developments in high pressure experimental petrology. Per Mineral 73(Special Issue 2):197–208

    Google Scholar 

  • Gaggero L, Cortesogno L, Bertrand JM (2004) The Pre-Namurian basement of the Ligurian Alps: a review of the Lithostratigraphy, pre-Alpine metamorphic evolution, and regional comparisons. Per Mineral 73(Special Issue 2):85–96

    Google Scholar 

  • Giacomini F, Bomparola RM, Ghezzo C (2005) Petrology and geochronology of metabasites with eclogite facies relics from NE Sardinia: constraints for the Palaeozoic evolution of Southern Europe. Lithos 82:221–248

    Article  Google Scholar 

  • Gil Ibarguchi JI, Abalos B, Azcarraga J, Puelles P (1999) Deformation, high-pressure metamorphism and exhumation of ultramafic rocks in a deep subduction/collision setting (Cabo Ortegal, NW Spain). J Metam Geol 17:747–764

    Article  Google Scholar 

  • Graham CM, Powell R (1984) A garnet–hornblende geothermometer: calibration, testing and application to the Pelona Schists, southern California. J Metam Geol 2:13–31

    Article  Google Scholar 

  • Guillot F, Schaltegger U, Bertrand JM, Deloule E, Baudin T (2002) Zircon U–Pb geochronology of Ordovician magmatism in the polycyclic Ruitor Massif (Internal W Alps). Int J Earth Sci 91:964–978

    Article  Google Scholar 

  • Heinrich W, Althaus E (1980) Die obereStabilitätsgrenze von Lawsonit plus Albit bzw. Jadeit Fortsch Mineral 58:49–50

    Google Scholar 

  • Haydoutov I (1987) Ophiolites and island arc igneous rocks in the Caledonian basement of the S. Carpathian–Balkan region. In: Flugel H, Sassi F, Grecula P (eds) Pre-Variscan and Variscan events in the Alpine-Mediterranean mountain belts. Alfa Publishers, Bratislava, pp 279–292

    Google Scholar 

  • Haydoutov I, Yanev S (1997) The Protomoesian microcontinent of the Balkan Peninsula—a peri-Gondwanaland piece. Tectonophysics 272:303–313

    Article  Google Scholar 

  • Haydoutov I, Kolcheva K, Daieva L-A, Savov I, Carrigan CW (2004) Island arc origin of the variegated formations from the east Rhodope, Bulgaria—implications for the evolution of the Rhodope Massif. Ofioliti 29:145–157

    Google Scholar 

  • Holland T, Blundy J (1994) Non-ideal interactions in calcic amphiboles and their bearing on amphibole–plagioclase thermometry. Contrib Mineral Petrol 116:433–447

    Article  Google Scholar 

  • Holland TJB (1983) The experimental determination of activities in disordered and short-range ordered jadeitic pyroxenes. Contrib Mineral Petrol 82:214–220

    Article  Google Scholar 

  • Holland TJB, Powell R (1998) An internally consistent thermodynamic data set for phases of petrological interest. J Metam Geol 16:309–344

    Article  Google Scholar 

  • Harrison TM (1981) Diffusion of 40Ar in hornblende. Contrib Mineral Petrol 78:324–331

    Article  Google Scholar 

  • Katskov N, Iliev K (1993) Explanatory note to the geological map of Bulgaria in scale 1:100000, Ihtiman sheet, Sofia

  • Kohn MJ, Spear FS (1990) Two new barometers for garnet amphibolites with applications to eastern Vermont. Am Mineral 75:89–96

    Google Scholar 

  • Kretz R (1983) Symbols for rock-forming minerals. Am Mineral 68:277–279

    Google Scholar 

  • Laird J, Albee AL (1981) Pressure, temperature, and time indicators in mafic schists: their application to reconstructing the polymetamorphic history of Vermont. Am J Sci 281:127–175

    Google Scholar 

  • Leake BE, Woolley AR, Arps CES, Birch WD, Gilbert MC, Grice JD, Hawthorne FC, Kato A, Kisch HJ, Krivovichev VG, Linthout K, Laird J, Mandarino JA, Maresch WV, Nickel EH, Rock NMS, Schumacher JC, Smith DC, Stephenson NCN, Ungaretti L, Whittaker EJW, Youzhi G (1997) Nomenclature of amphiboles: report of the subcommittee on amphiboles of the International Mineralogical Association. Commission on new minerals and mineral names. Can Mineral 35:219–246

    Google Scholar 

  • Medaris LG Jr, Ducea M, Ghent E, Iancu V (2003) Condition and timing of high-pressure Variscan metamorphism in the South Carpathians, Romania. Lithos 70:141–161

    Article  Google Scholar 

  • Morimoto N (1988) Nomenclature of pyroxenes. Schweiz Mineral Petrogr Mitt 68:95–111

    Google Scholar 

  • Mukasa SB, Haydoutov I, Carrigan CW, Kolcheva K (2003) Thermobarometry and 40Ar/39Ar ages of eclogitic and gneissic rocks in the Sredna Gora and Rhodope terranes of Bulgaria. J Czech Geol Soc 48:94–95

    Google Scholar 

  • Nakamura N (1974) Determination of REE, BA, Fe, Mg, Na and K in carbonaceous and ordinary chondrites. Geochim Cosmochim Acta 38:757–775

    Article  Google Scholar 

  • Nitsch K-H, Winkler HGF (1965) Bildungsbedingungen von Epidot und Orthozoisit. Beitr Min Petr 11:470–486

    Article  Google Scholar 

  • O’Brien PJ, Carswell DA, Gebauer D (1990) Eclogite formation and distribution in the European Variscides. In: Carswell DA (ed) Eclogite facies rocks. Blackie and Son Ltd, Glasgow, pp 204–224

    Google Scholar 

  • O’Brien PJ (2000) The fundamental Variscan problem: high temperature metamorphism at different depths and high-pressure metamorphism at different temperatures. In: Franke W, Haak V, Oncken O, Tanner D (eds) Orogenic processes: quantification and modelling in the Variscan Belt. Geol Soc London Spec Publ 179, pp 369–386

  • Paquette JL, Ménot RP, Peucat JJ (1985) Sm-Nd and U-Pb zircon study of eclogites from the Alpine External massifs (Western Alps): evidence for crustal contamination. Earth Planet Sci Lett 96:181–198

    Article  Google Scholar 

  • Paquette JL, Montel JM, Chopin C (1999) U-Th-Pb dating of the Brossasco ultrahigh-pressure metagranite, Dora-Maira massif, western Alps. Eur J Mineral 11:69–77

    Google Scholar 

  • Pattison DRM (1992) Stability of andalusite and sillimanite and the Al2SiO5 triple point: constraints from the Ballachulish aureole, Scotland. J Geol 100:423–446

    Article  Google Scholar 

  • Pearce JA, Parkinson IJ (1993) Magmatic processes and plate tectonics. Geol Soc Spec Publ 76:373–403

    Article  Google Scholar 

  • Rieder M, Cavazzini G, D’Yakonov YS, Frank-Kamenetskii VA, Gottardi G, Guggenheim S, Koval PV, Muller G, Neiva AMR, Radoslovich EW, Robert J-L, Sassi FP, Weiss Z, Wones DR (1998) Nomenclature of Micas. Can Mineral 36:905

    Google Scholar 

  • Rock NMS (1990) The International Mineralogical Association (IMA/CNMMN) Pyroxene nomenclature scheme: computerization and its consequences. Mineral Petrol 43:99–119

    Article  Google Scholar 

  • Rötzler K, Schumacher R, Maresch W, Willner AP (1998) Characterization and geodynamic implication of contrasting metamorphic evolution in juxtaposed high pressure units at the Western Erzebirge (Saxony, Germany). Eur J Mineral 10:261–280

    Google Scholar 

  • Spear FS, Kohn MJ, Cheney JT (1999) P-T paths from anatectic pelites. Contrib Mineral Petrol 134:17–32

    Article  Google Scholar 

  • Villa IM, Grobéty B, Kelley SP, Trigila R, Wieler R (1996) Assessing Ar transport paths and mechanisms in the McClure Mountains hornblende. Contrib Mineral Petrol 126:67–80

    Article  Google Scholar 

  • Villa IM, Hermann J, Müntener O, Trommsdorff V (2000) 39Ar–40Ar dating of multiply zoned amphibole generations (Malenco, Italian Alps). Contrib Mineral Petrol 140:363–381

    Article  Google Scholar 

  • von Raumer JF, Stampfli GM, Borel G, Bussy F (2002) Organization of pre-Variscan basement areas at the north-Gondwanan margin. Int J Earth Sci 91:35–52

    Article  Google Scholar 

  • von Raumer JF, Stampfli GM, Bussy F (2003) Gondwana-derived microcontinents—the constituents of the Variscan and Alpine collisional orogens. Tectonophysics 365:7–22

    Article  Google Scholar 

  • Winchester JA, Floyd PA (1977) Geochemical magma-type discrimination; application to altered and metamorphosed basic igneous rocks. Earth Planet Sci Lett 28:459–469

    Article  Google Scholar 

  • Wood BJ, Banno D (1973) Garnet–orthopyroxene and orthopyroxene–clinopyroxene relationships in simple and complex systems. Contrib Mineral Petrol 42:109–124

    Article  Google Scholar 

  • Yanev S (2000) Palaeozoic terranes of the Balkan Peninsula in the framework of Pangaea assembly. Palaeogeogr Palaeoclimatol Palaeoecol 161:151–177

    Article  Google Scholar 

  • Zagorchev I, Dabovski H, Chunev D (1973) On the tectonics of the western part of the Sredna Gora crystalline block (Sredna Gora proper). Rev Bulg Geol Soc 34:1–10

    Google Scholar 

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Acknowledgments

This research was carried out within the bilateral CNR (Italy)–BAN (Bulgaria) project. The reviews by F.M. Brouwer, Ingo Braun and an anonymous referee helped us to improve the early versions of the manuscript.

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Authors and Affiliations

  1. Department for the Study of the Territory and its Resources, University of Genoa, Corso Europa 26, 16132, Genoa, Italy

    Laura Gaggero, Laura Buzzi & Luciano Cortesogno

  2. Geological Institute of the Bulgarian Academy of Sciences, Acad. Georgi Bontchev, Str. Block 24, 1113, Sofia, Bulgaria

    Ivan Haydoutov

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  1. Laura Gaggero
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  2. Laura Buzzi
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  3. Ivan Haydoutov
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  4. Luciano Cortesogno
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Correspondence to Laura Gaggero.

Additional information

Luciano Cortesogno is deceased.

Mineral abbreviations are after Kretz (1983).

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Gaggero, L., Buzzi, L., Haydoutov, I. et al. Eclogite relics in the Variscan orogenic belt of Bulgaria (SE Europe). Int J Earth Sci (Geol Rundsch) 98, 1853–1877 (2009). https://doi.org/10.1007/s00531-008-0352-x

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