PETROGRAFIE A GEOCHEMIE MIGMATITŮ Z LOMU VANOV U TELČE
Roč.17,č.1-2(2010)
The migmatites from the Vanov quarry are considerable rock type of the Moldanubian Zone in the Bohemian Massif. According to their microstructure, the most common are stromatic migmatites, accompanied by massive migmatites (diatexites) and agmatites. Biotite is comparatively Mg rich (Mg-siderophyllite) with XMg = 0.38–0.61 and Al content 1.49–1.63 apfu. The XMg of cordierite is similar (0.58–0.61). If compared to the composition of continental crust, mesosome of stromatitic migmatites is enriched in Rb, Ba, Ce and Zr. The origin of leucosome is controlled by partial melting of the original biotite-rich metasediments, accompanied by depletion in Ce, Zr and Y and origin of positive Eu anomaly.
Moldanubian Zone; migmatite; petrography; geochemistry; biotite; cordierite
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