METAMORFNÍ VÝVOJ ŽELEŠICKÉHO AMFIBOLITOVÉHO TĚLESA (BRNĚNSKÝ MASIV)
Roč.12,(2005)
The Želešice amphibolite body is situated along the southwestern margin metadiorite belt in the Central Basic belt of the Brno Massif. The metabasites and associated rocks (ultramafic rocks and biotite gneisses) comprise a metamorphic complex less than 2 km thick. The sequence of mafic and ultramafic metavulcanic rocks overlying metasediments probably represents the upper part of the ophiolite. The mineral assemblage metabasites (Pl + Hbl ± Bt ± Ep ± Qtz ± Act) and amphibole chemical zonation indicate polyphase metamorphic evolution. Three metamorphic evolutionary stages can be distinguished: (i) regional metamorphism (M1) in amphibolite facies grade (> 5 kbar, 550-650 °C), (ii) contact metamorphism (M2) related to the intrusion of the Cadomian granitoids (650-700 °C, ~ 6 kbar), (iii) the Variscan metamorphism (M3) under greenschist facies conditions (450-530 °C for 2 kbar).
Brno Massif; amphibolites; ultramafic rocks; PT conditions
Buriánek, D. (2000): Mramory v metadioritové subzóně brněnského masivu. - Geol. výzk. Mor. Slez. v r. 2000, 8, 74-76.
Dudek, A. - Suk, M. (1964): Zpráva o geologickém mapování brněnského masivu na listu Modřice. - Zpr. Geol. Výzk. v r. 1963, 60-62.
Dudek, A. (1995): Metamorphic evolution of the Moravo-Silesian basement. - In: Dallmeyer, R.D., Franke, W., Weber K. (eds), PrePermian Geology of Central and Eastern Europe, 508-511.
Finger, F. - Tichomirova, M. - Pin, C. - Hanžl, P. (2000): Relics of an Early-Panafricanensimatic metabasitemetarhyolite formation in the Brno Massif, Eastern Czech Republic. - International Journal of Earth Science (Geol. Rundschau), 89, 328-335.
Hanžl, P. - Krejčí, Z. - Vít, J. - Otava, J. - Novák, Z. - Stráník, Z. (1999): Geologická mapa Brna a okolí 1:50 000. - Praha, Český geologický ústav.
Hanžl, P. - Melichar, R. - Leichmann, J. (1999): Excursion Guide. - Geolines, Praha : IG AV ČR Praha, 8, s. 79-94.
Hanžl, P. Melichar, R. (1997): The Brno Massif: a Section through the Active Continental Margin or Composed Terrane. - Krystalinikum, 23, 33-58.
Holdaway, M. J. - Mukhopadhyay, B. (1993): A reevaluation of the stability relations of andalusite: Thermochemical data phase diagram for the aluminum silicates. - Am. Mineralogist, 78, 298-315.
Holetz, F. (1923): Der Hornblendit und die ihn begleitenden Gesteine von Schöllschitz bei Brünn. Lotos, Bd. 71, 121-142.
Jelínek, E. - Dudek, A. (1993): Geochemistry of subsurface Precambrian plutonic rocks from the Brunovistulian complex in the Bohemian massif, Czechoslovakia - Precambrian Research, 62, 103-125.
Jenkins, D.M. (1981): Experimental phase relations of hydrous peridotites modelled in the system H2OCaOMgOSiO2 - Contrib. Mineral. Petrol., 77, 166-176.
Kretz, R. (1983): Symbols for rock forming minerals. Amer. Mineralogist, 68, 277279.
Leake, B. E. - Woolley, A. R. - Arps, C. E. S. - Birch, W. D. - Gilbert, M. C. - Grice, J. D. - Hawthorne, F. C. - Kato, A. - Kisch, H. J. - Krivovichev, V. G. - Linthout, K. - Laird, J. - Mandarino, J. - Maresch, W. V. - Nickel, E. H. - Rock, N. M. S. - Schumacher, J. C. - Smith, D. C. - Stephenson, N. C. N. - Ungaretti, L. - Whittaker, E. J. W. - Youzhi, G. (1997): Nomenclature of amphiboles. Report of the Subcommittee on Amphiboles of the International Mineralogical Association Commission on New Minerals and Mineral Names. - Eur. J. Mineral., 9, 623-651.
Leichmann, J. (1996): Geologie und Petrologie des Brünner Massivs. - PhD thesis, University of Salzburg.
Schumacher, J. (1996): The estimation of the proportion of ferric iron in the electron-microprobe analysis of amphiboles. - Can. Mineral. 34, 238246.
Sun, S.S. (1982): Chemical composition and origin of the Earths primitive mantle. Geochim. Cosmochim. Acta, 46, 179-192.
Štelcl, J. - Weiss, J. a kol. (1986): Brněnský masív. 1-255. Brno
Turner, F.J. (1981): Metamorphic Petrology, Mineralogical, Field, and Tectonic Aspects. - McGraw Hill Book Co., New York, 524p.