XENOLITY MRAMORŮ UZAVŘENÉ V TONALITECH BUDISLAVSKÉHO MASIVU (POLIČSKÉ KRYSTALINIKUM)

Roč.9,(2002)

David Buriánek

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Abstrakt
The xenolithes of marbles were studied in the quarry near Budislav at northern part of the Budislav massif (Polička crystalline complex). Two distinct zones progressing from tonalite to marble were distinguished: (I) endocontact: Di + Pl + Qtz + Ttn, (II) exocontact: Wo + Di ± Grs ± Ves. Mineral assemblages of marbles, calc-silicate rocks and skarns indicate temperature 670-550 °C for pressure 4 kbar. These data are in good agreement with PT values obtained for tonalites (690-656 °C a 5,2-2,5 kbar) and suggest that pressure under 4 kbar for formation contact mineral assemblages is unrealistic. Mineral assemblages on contact with aplite dykes indicate lower temperature (550 a 520 °C) for pressure 4 kbar.

Klíčová slova:
Polička crystalline complex; Budislav massif; contact metamorphism; calc-silicate rocks; PT conditions
Reference

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