U-PB ZIRCON AND SM-ND DATING OF MOLDANUBIAN HP HT GRANULITES FROM SOUTH BOHEMIA, CZECH REPUBLIC/

Conventional multigrain U-Pb systematics of zircon and single-grain ev aporation data of zircons in combination with Nd model ages are presen ted for pyroxene-free, felsic, garnetiferous granulites and orthopyrox ene-bearing granulites of felsic, mafic and intermediate composition f rom the Blansky Les mountains granulite complex, S Bohemia. Zircons fr om mafic and intermediate granulites yield Concordia intercept ages be tween 346 +/- 5 and 351 +/- 6 Ma as well as a single-grain evaporation age of 346 +/- 12 Ma. These ages define the time of Variscan high-gra de metamorphism in S Bohemia and are supported by an internal Sm-Nd ga rnet-zircon-plagioclase-whole rock isochron age of 343 +/- 21 Ma. Euhe dral zircons from felsic granulites of probable granitic derivation yi eld U-Pb ages of 366 +/- and 373 +/- 12Ma interpreted as intrusion age s of the granitic precursor. An inherited Proterozoic crustal componen t is documented by poorly defined Concordia upper intercept ages aroun d 1700 Ma and Nd-model ages between 1.3 and 2.1 Ga.