The acid metavolcanic rocks of the Orlica-Śnieżnik Dome (Sudetes): their origin and tectono-metamorphic evolution

• Autorzy: Murtezi, M.
• Języki publikacji: EN

Abstrakty

EN

The Orlica-Śnieżnik Dome (OSD) belongs to the mosaic of geological units forming the Sudetic part (NE margin of the Bohemian Massif) of the Variscan belt. Acid metavolcanic rocks referred to as leptites appear in the OSD as intercalations in the mica schists of the Stronie Formation - the supracrustal cover of the gneiss core of the unit. Two types of acid meta-volcanogenic rocks have been distinguished: massive leptites (ML) and biotite-bearing leptites (BBL); together they are referred the leptite series. The ML originate from acid volcanic rocks that could have contained only small amounts of sedimentary material. The BBL are metamorphosed tuffites with a variable share of sedimentary material. All the analysed leptites from the entire OSD area reveal similar geochemical characteristics. The high concentration of strongly incompatible elements such as REE, as well as the enrichment in large-ion-lithophile elements indicates the continental crust affinities of the leptites' protolith. On the other hand, ascertained the high Th/Ta ratios, negative Nb and Ta anomalies, and low Ti, Zr and Hf content can be interpreted as indicators of magmatism connected with a suprasubduction environment. Such ambiguous characteristics may indicate that an ensialic rift environment, considered as the place of origin for the magmatic rocks dated at c. 500 Ma and occurring in the OSD, developed due to extension behind a collisional zone of Lower Palaeozoic age. An extensional environment created during this event could be the location for the postulated early deformation and metamorphism of the Stronie Formation. The Śnieżnik metagranites would have been emplaced into such, already deformed, supracrustal cover. The signature of an active margin found in these continental crust rocks that were stretched and melted due to the increased heat transfer resulted from an earlier (Neoproterozoic?) tectono-thermal episode. The reconstructed path of the tectono-metamorphic evolution of the leptites entirely results from a Variscan collisional episode occurring in the borderland of the West and the East Sudetes. The sequence of the deformations established for the studied rocks is interpreted as an effect of the continuous convergence of crustal units in an E-W direction. Structural and phase-equilibria lines of evidence show that the tectono-metamorphic evolution of the Stronie Formation was that of early burial (D1) to a depth not exceeding upper amphibolite facies conditions, and subsequent uplift connected with subvertical shortening and flattening strain (D2). As a result of the continuous convergence, thrusting took place along the edges of the colliding units. The final adaptation of the colliding crustal slices led to zonal lateral oblique displacements (D3). This latter event is treated as the cause for disturbance of the isograd and isotherm pattern observed within the rocks of the Stronie Formation. It is also responsible for zonal shearing, generally taking place in a N-S direction. During the collision that occurred along the eastern margin of the OSD, the rocks of the Stronie Formation reached the highest P-T conditions of metamorphism at c. 9 kbar and 650°C. The presented data shows a considerable decrease in the peak-metamorphic conditions from the east to the west of the OSD.

Słowa kluczowe

EN

sacid metavolcanic rocks; geochemistry; petrogenesis; P-T-d path; Stronie Formation; Orlica-Śnieżnik Dome

• Czasopismo: Geologia Sudetica
• Rocznik: 2006
• Tom: Vol. 38
• Strony: 1-38
• Opis fizyczny: Bibliogr. 74 poz.

Twórcy

autor

Murtezi, M.

• Institute of Geological Sciences of the Polish Academy of Sciences, Department of Geology of the Sudetes, Podwale 75, 50-449 Wrocław, Poland,

Bibliografia

• ALEKSANDROWSKI, P. & MAZUR, S., 2002. Collage tectonics in the northeasternmost part of the Variscan Belt: the Sudetes, Bohemian Massif. In: Winchester, J. A., Pharaoh T. c., Verniers, J. (Eds.), Palaeozoic Amalgamation of Central Europe, Geological Society of London Special Publications, 201: 237-277.
• ANDERS, E. & GREVESSE, N., 1989. Abundances of the elements: met eoric and sol ar. Geochimica et Cosmo- chimica Acta, 53: 197-214.
• BAKUN-CZUBAROW, N., 1991. Geodynamic signif-cance of the Variscan HP eclogite-granulite series of the Złote Mountains in the Sudetes. Publications of the Institute of Geophysics, Polish Academy of Sciences, 236: 215-244.
• BAKUN-CZUBAROW, N., 1998. Ilmenite-bearing eclogites of the West Sudetes - their geochemistry and mineral chemistry. Archiwum Mineralogiczne, 51: 29-110.
• BONIN, B., 1990. Orogenic to Non-Orogenic Magmatic Events: Overview of the Late Variscan Magmatic Evolution of the Alpine Belt. Turkish Journal of Earth Sciences, 7: 133-143.
• BORKOWSKA, M., CHOUKROUNE, P., HAMEURT, J. & MARTINEAU, F., 1990. A geochemical investigation of age, significance and structural evolution of the Caledo-nian-Variscan granite-gneisses of the Snieżnik metamorphic area (central Sudetes, Poland). Geologia Sudetica, 25: 1-27.
• CYMERMAN, Z., 1996. The Złoty Stok-Trzebie- szowice ret gional shear zone: the boundary of terranes in the Góry Złote Mts. (Sudetes). Kwartalnik Geologiczny, 40: 89-118.
• CYMERMAN, Z., 1997. Structure, kinematics and an evolution of the Orlica-Snieżnik Dome, Sudetes. Prace Państwowego Instytutu Geologicznego, 9: 114-115.
• DEPCIUCH, T., 1972. Absolute age of (K-Ar) granitoids from the Kłodzko - Zloty Stok area and the Niemcza zone. Kwartalnik Geologiczny, 16: 103-112.
• DON, J., 1989. On the position of the eclogites within the Gieraltów gneisses of Międzygórze (Snieżnik metamorphic massif - Sudetes). In: Indicat ors of structural evolut ion in polyphase deformed metamorphic complexes: criteria for the distinction of para- and orthogneisses, the Orlica-Snież-nik dome, west Sudetes. Polish Academy of Sciences, Instute of Geological Sciences, Wroclaw, pp. 44-58.
• DON, J., 2001. The relicts of the metamorphic envelope rocks and their arrangement within Gieraltów migmatites massif. Mineralogical Society of Poland Special Papers, 19: 214-271.
• DON, B. & DON, J., 1960. Geneza rowu Nysy na tle badań wykonanych w okolicach Idzikowa. Acta Geologica Polonica, 10: 78-106.
• DON, J., DUMICZ, M., WOJCIECHOWSKA, I. & ŻELAŹ-NIEWICZ, A., 1990. Lithology and tectonics of the Orlica-Snieżnik Dome, Sudetes - Recent State of Knowledge. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen, 197:159-188.
• DON, J., SKÄCEL, J. & GOTOWAŁA, R., 2003. Geological Map of the Snieżnik Metamorphic Unit, Stare Mesto Zone and Velke Vrbno Dome, scale 1:50000, Wroclaw Univeri sity.
• DUMICZ, M., 1976. Próba wyjaśnienia tektogenezy serii zmeta-morfizowanej Ziemi Kłodzkiej (in:) Probt em wieku deformacji serii zmetamorfizowanych Ziemi Klodzkiej. Materialy Konferencji Terenowej 11-12.09.1976. Uniwersytet Wrocla-wski, pp. 9-37.
• DUMICZ, M., 1979. Tectogenesis of the metamorphosed seriesof the Klodzko Dist rict: a tent at ive explanat ion. Geologia Sudetica, 14: 29-46.
• DUMICZ, M., 1988. Zloty Stok - Skrzynka structural element in the light of mesostructural analysis of Lądek - Snieżnik.Geologia Sudetica, 23: 83-106.
• DUMICZ, M., 1995. Problem zwrotu ruchu mas skalnych w ewolucji tektonometamorficznej metamorfiku SnieżnikaGeologia Sudetica, 29: 19-29.
• EBY, G. N., 1992. Chemical subdivision of the A-type granitoids:Petrogenetic and tectonic implications. Geology, 20: 641-644.
• FISHER, G., 1936. Der Bau des Glatzer Schneegebirges. Jahrbuch der Preußischen Geologischen Landesanstalt, 56: 712732.
• FLOYD, P.A. & WINCHESTER, J.A., 1978. Identification and Discrimination of Altered and Metamorphosed Volcanic Rocks Using Immobile Elements. Chemical Geology, 21: 291-306.
• FLOYD, P. A., WINCHESTER, J.A., CIESIELCZUK, J., LEWANDOWSKA, A., SZCZEPAŃSKI, J. & Turniak, K., 1996. Geochemi st ry of early Palaeozoic amphibol ites from the Orlica-Snieżnik Dome, Bohemian mass if: petro-genesis and paleotectonic aspects. Geologische Runschau, 85: 225-238.
• FRANKE, W. & ŻELAŹNIEWICZ, A., 2000. The eastern terminat ion of the Variscides: terrane corr el at ion and kinematic evol ution. In: Franke, W., Haak, V. & Oncken, O., (Eds), Orogenic processes: Quantification and Modelling in the Variscan Belt. Geological Society of London Special Publica tions, 179: 63-86.
• GORTON, M. P. & SCHANDL, E. S., 2000. From continents to isl and arcs: a geochemi cal index of tect onic sett ing for arc-related and within-plate felsic to intermediate volcanic rocks. Canadian Mineralogist, 38: 1065-1073.
• GREEN, T. H. & PEARSON, N.J., 1987. An experi ment al. study of Nb and Ta partitioni ng between Ti-rich minerals and silicate liquids at high pressure and temperatures. Geochimica et Cosmochimica Acta, 51: 55-62.
• GRUNOW, A., HANSON, R. & WILSON, T., 1996. Were aspects of Pan-African deformation linked to Iapetus opening? Geology, 24: 1063-1066.
• GRZESKOWIAK, A. & ŻELAŹNIEWICZ, A., 2002. On the Significance of Gneissic Enclaves in the 500 Ma Metagranite, the Ladek-Śnieżnik Metamorphic Unit, the West Sudetes.Geolines, 14: 28-29.
• HANSEN, J., SKJERLIE, K. P., PEDERSON., R.B. & DE LAROSA, J., 2002. Crustal melting in the lower parts of island arc: an example from the Bremanger Granitoid Complex, west Norwegian Caledonides. Contributions to Mineralogy and Petrology, 143: 316-335.
• HARRIS, N. B. W., PEARCE, J. A. & TINDLE, A. G., 1986.Geochemical characteristics of collision-zone magmatism. (in:) Coward MP, Reis AC (eds.) Collision tectonics. Geological Society of London, Special Publications, 19: 67-81
• .HOLLAND, T. J. B. & POWELL, R., 1998. An internally consistent thermodynamic data set for phases of petrological interest, Journal of Metamorphic Geology, 16: 309-343.
• HROUDA, F., SCHULMANN, K., CHLUPACOVA, M., AICHLER, J., MIXA, P., PECINA, V., ZACEK, V. & KRÖNER, A., 2003. Magnetic fabric in granitoid plutons emplaced duri ng Variscan orogeny and timi ng of their in-trutions: Eastern Variscan front. Geophysical Research Abstracts, 5, abstract number 09332.
• INGER, S. & HARRIS, N., 1993. Geochem ical constraints on leucogranite magmatism in the Langtang valley, Nepal Himalaya. Journal of Petrology, 34: 345-368.
• KOZŁOWSKA-KOCH, M., 1973. Polimetamorfity strefy tektonicznej Zloty Stok-Skrzynka w Sudetach. Geologia Sudetica, 8.
• KRETZ, R., 1983. Symbols for rock-forming minerals. American Mineralogist, 68: 277-279.
• KRÖNER, A., JAECKEL, P., HEGNER, E. & OPLETAL, M., 2001. Single zircon ages and whole-rock Nd isotopic systematic of early Palaeozoic granitoid gneisses from the Czech and Poli sh Sudetes (Jizerske hory, Karkonosze Mountains and Orlica-Snieżnik Complex). International Journal of Earth Science, 90: 304-324.
• KRÖNER, A., JAECKEL, P. & OPLETAL, M., 1994. Pb-Pb and U-Pb zircon ages for orthogneisses from Eastern Bohemia: further evidence for a major Cambro-Ordovician magmatic event. Journal of Czech Geological Society, 39: 61.
• KRYZA, R. & PIN, c., 1997. Cambrian/Ordowician magma-tism in the Polish Sudetes: noevi dence for subduction re lated setting. Terra Nova, 9: 144.
• KRYZA, R., PIN, c. & VIELZEUF, D., 1996. High-press ure granulites from the Sudetes (south-west Poland): evidence of crustal subduction and collisional thicken ing in the Vari-scan Belt. Journal of Metamorphic Geology, 14: 531-546.
• KUSTER, D. & LIEGEOIS, J. P., 2001. Sr, Nd isotopes and geo-chemi st ry of the Bayuda Desert high-grade metamorphic basement (Sudan): an early Pan-African oceanic convergent margin, not the edge of the East Saharan ghost craton? Precambrian Research, 109: 1-23.
• LANGE, U., BROKER, M., MEZGER, K. & ŻELAŹNIEWICZ, A., 2003. The orthogneisses of the Orlica-Snieżnik Dome (West Sudetes, Poland): Sr-Nd isotope characteri stic and geochronology of micas. Journal of Czech Geological Society, Special Issue.
• MANIAR, P.D. & PICCOLI, P.M., 1989. Tectonic discrimination of granitoids. Geological Society of America Bulletin, 101: 635-643.
• MATTE, P. H., MALUŚKI, H., RAJLICH, P. & FRANKE, W., 1990. Terrane boundaries in the Bohemian Massif: results of large-scale Variscan shear-ng. Tectonophysics, 177: 151-170.
• OLIVER, G. J. H., CORFU, F. & KROGH, T. E., 1993. U-Pb ages from SW Poland: evidence for Caledonian suture zone between Baltica and Gondwana. Journal of the Geological Society, London, 150: 355-369.
• PEARCE, J. A., 1983. Role of the sub-continental litosphere in magma genesis at active continental margins. In: HAW-KENSWORTH, c. J. & NORRY, M. J., (Eds.), Continental basalts and mantle xenoliths. Shiva, Nantwich, pp. 230-249.
• PEARCE, J. A., HARRIS, N. B. W. & TINDLE, A. G., 1984.Trace element discrimination diagrams for the tectonic in terpretation of granitic rocks. Journal of Petrology, 25: 956983.
• PIN, C. & MARINI, F., 1993. Early Ordovician continent al break-up in Variscan Europe: Nd-Sr isotope and trace ele -ment evidence from bimodal igneous associations of the southern Massif Central, France. Lithos, 29: 177-196.
• POWELL, R. & HOLLAND, T. J. B., 1988. An internally consistent dataset with uncertainties and correlations; 3, Applications to geobarometry, worked examples and a computer program. Journal of Metamorphic Geology, 6: 173-204.
• VON RAUMER, J. F., STAMPFLI, G. M., BOREL, G. & BUSSY, F., 2001. The organizat ion of pre-Variscan basement areas at the Gondwana margin. International Journal of Earth Sciences, 90, (online published).
• ROMANOVA, M. & ŚTIPSKA, P., 2002. The Determination of the PT Conditions during Transition from Steep Syn-Extrusional Fabrics to Hori zont al: NE Snieznik Do -main. Geolines, 14: 80.
• RUDNICK, R. & FOUNTAIN, D., 1995. Nature and composition of the continent al crust: A lower crustal perspective. Reviews of Geophysics, 33:3.
• RYKA, W. & MALISZEWSKA, A., 1991. Słownik Petrograficzny. Wydawnictwa Geologiczne, Warszawa.
• SCHULMANN, K. & GAYER, R., 2000. A model for a continental accretionary wedge developed by oblique colision: The NE Bohemian Massif. Journal of the Geological Society, Lon don, 157: 401-416.
• SKACEL, J., 1981. Geologie des Kristallinikums in der Umge-bunge der Stadt Jesenik, Acta Universitatis Palackianae Olo-moucensis, Facultas Rerum Naturalium, 70: 107-126.
• SKACEL, J., 1989. On the Lugicum - Silesicum Boundary Acta Universitates Wratislaviensis, 1113, Prace Geologiczno- Mineralogiczne, 17: 45-55.
• SMULIKOWSKI,K., 1979. Ewolucja polimetamorficzna krystaliniku Snieżnika Kłodzkiego i Gór Złotych w Sudetach. Geologia Sudetica, 14: 7-76.
• STAWIKOWSKI, W., 2002. Contacts between high-P eclogites and gneisses in the Ladek-Snieżnik metamorphic unit, the West Sudetes. Geolines, 14: 84-86.
• STAWIKOWSKI, W. & RHEDE, D., 2003. Mineralogi cal Divers ity of Fels ic Rocks at Cont acts with Eclogites in the Orlica-Snieżnik Dome, West Sudetes. Geolines, 16: 98-99.
• SZCZEPAŃSKI, J., ANCZKIEWICZ, A., MAZUR, S. & THIRNWALL, M., 2004. Constraints on timi ng of ult rahigh pressure metamorphism in the Orlica-Snieżnik Dome, West Sudetes. Mineralogical Society of Poland, Special Papers, 24: 365-368.
• TAKAHASHI, Y., SHIMIZU, H., KAGI, H., YOSHIDA, H., USAI, A. & NOMURA, M., 2000. A new method for the determination of CeIII/CeIV ratios in geological materials; application for weathering, sedimentary and diagenetic processes. Earth and Planetary Scientific Leters, 182: 201-207.
• THOMPSON, R. N., 1982. British Tertiary volcanic province. Scottish Journal of Geology, 18: 49-107.
• TURNIAK, K., MAZUR, S. & WYSOCZAŃSKI, R., 2000. SHRIMP zircon geochronology and geochemistry of the Orlica-Snieżnik gneisses (Variscan belt of Central Europe) and their tectonic implications. Geodinamica Acta, 13: 393-312.
• VANCE, D. & MAHAR, E., 1998. Pressure-temperature paths from P-T pseudosections and zoned garnets: potential, limitations and examples from the Zanskar Himalaya, NW India. Contributions to Mineralogy and Petrology, 132:225-245.
• WHALEN, J. B., CURRIE, K. L. & CHAPELL, B. W., 1987. A-type granites: Geochemical characteristics, discrimination and petrogenesis. Contributions to Mineralogy and Petrology, 95: 407-419.
• WHALEN, J. B., ROGERS, N., VAN STAAL, c. R.,LONGSTAFFE, F. J., JENNER, G. A. & WINCHESTER, J. A., 1998. Geochem-cal and isot opic (Nd, O) data from Ordovician felsic plutonic and volcanic rocks of the Miramichi Highlands: petrogenetic and metallogenic implications for the Bathurst Mining Camp. Canadian Journal of Earth Sciences, 35: 237-252.
• WINCHESTER, J. A. & FLOYD, P. A., 1977. Geochemical discrimination of different magma series and their differentiation products using immobile elements. Chemical Geology,20: 325-343.
• WOJCIECHOWSKA, I., 1972. Preliminary results of investigation on so-called "Quartzites" in the neighbourhood of Romanowo (Stronie Complex), NW part of Krowiarki (East Sudetes). Bulletin of the Polish Academy of Sciences, Earth Sciences, 20: 273-277.
• WOJCIECHOWSKA, I., GUNIA, P. & ZIÓŁKOWSKA-KOZDRÓJ, M., 2000. Geochemistry of the "Haniak Gneisses" and their metabasic enclaves (Złoty Stok -Skrzynka Tect onic Zone, Eastern Sudetes, SW Pol and) -preliminary results. Bulletin ofthe Polish Academy of Sciences, Earth Sciences, 48: 45-60.
• WOJCIECHOWSKA, I., ZIÓŁKOWSKA-KOZDRÓJ, M. & GUNIA, P., 2001. Petropgraphy and geochemistry of leptites from the Skrzynka dislocation zone (Eastern Sudetes, SW Po- and) - pre-im-nary results. Bulletin of the Polish Academy ofSciences, Earth Sciences, 49: 1-15.
• ZELLMER, G. F., TURNER, S. P., HAWKESWORTH, c. J.,2000. Timescales of de-truc-ive plate margin magmatism: new insights from Santorini, Aegean volcanic arc. Earth and Planetary Science Letters, 174: 265-282.
• ŻELAZNIEWICZ, A., 1976. Tectonic and metamorphic events in the Polish part of the Orlica Mts. Zjawiska tektoniczne i metamorficzne w polskiej części Gór Orlickich. Geologia Sudetica, 11: 101-177.
• ŻELAZNIEWICZ, A., 1978. Maj or tec- onic struc-ures in the Polish part of Góry Orlickie. Geologia Sudetica, 13: 67-86.
• ŻELAZNIEWICZ, A., 1988. Orthogneisses due to irrotational extension, a case from the Sudetes, Bohemian massif. Geologische Rundschau, 77: 671-682.
• ŻELAZNIEWICZ, A. & BAKUN-CZUBAROW, N., 2002. A polyphase Exhumation of Ultra-High-P Eclogites from Nowa Wieś in the Ladek-Śnieżnik Metamorphic Unit, the Sudetes. Geolines, 14; 107-108.
• ŻELAZNIEWICZ, A., MAZUR, S. & SZCZEPAŃSKI, J., 2002. The Ladek-Snieżnik Metamorphic Unit - Recent State of Knowledge. Geolines, 14: 115-125.