CHLORITICKÝ HORNBLENDIT S OLIVÍNEM A SPINELEM Z LOUKOVIC U MORAVSKÝCH BUDĚJOVIC (MOLDANUBIKUM, ZÁPADNÍ MORAVA)

Stanislav Houzar, David Buriánek

Abstrakt

Ultramafic rock was found in the Varied Group of Moldanubicum near Loukovice (western Moravia). It is composed predominantly by chlorite and amphibole, locally rich in ferroan spinel and serpentinised magnesian olivine (Fo = 73–81 mol. %). Their current mineral assemblage originally corresponded to pyroxenic peridotite (olivine and/or pyroxene-rich rock) metamorphosed under upper amphibolite facies conditions. Older mineral assemblage Ol + Cpx + Opx + Sp indicates the temperature 786–804 °C for pressures near 8 kbar. Amphibole (magnesiohornblende) and chlorite (clinochlore) formed during the metamorphosis at temperatures of 714 ± 34 °C and expected pressures around 8 kbar or less.

Bibliografická citace

Houzar, S., & Buriánek, D. (2012). CHLORITICKÝ HORNBLENDIT S OLIVÍNEM A SPINELEM Z LOUKOVIC U MORAVSKÝCH BUDĚJOVIC (MOLDANUBIKUM, ZÁPADNÍ MORAVA). Geologické výzkumy na Moravě a ve Slezsku, 19(1-2). Získáno z https://journals.muni.cz/gvms/article/view/1658

Klíčová slova

spinel, olivine, chlorite hornblendite, P-T conditions, Varied Group, Moldanubicum

Plný Text:

Reference

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