Acta Musei Moraviae

Peraluminous granite from the southern edge of the Třebíč pluton

Peraluminous granites are common rock types in the southern edge of the Třebíč pluton, Moldanubicum, Bohemian Massif. Based on petrographical data are subdivided on the biotite, garnet-biotite and tourmaline-biotite granites. Biotite and garnet-biotite granites are products biotite dehydratation melting. However biotite rich enclaves, chemical and isotopic compositions indicated that magma mixing occurs between crust derivated garnet-biotite granite melt and hybrid granitoids (durbachite). The crystalization ages granites an their enclaves obtained from monazite (CHIME, ~323 Ma) are younger then age of durbachite intrusion (~335 Ma; KOTKOVÁ et al. 2003). Biotite and garnet-biotite granites represent independent intrusion generated during initial phases postorogenic magmatic activity in the Moldanubicum, as the result interaction between late durbachite melt and crustal melt. Younger tourmaline-biotite granite and pegmatite veins were generated from B-rich and F poor residual melt on the end of the crystallisation of biotite and garnet-biotite granites.