U–Pb zircon and Rb–Sr whole-rock analyses from various gneisses and plutonie rocks of the Moldanubian and Moravo-Silesian zones and the stable foreland of the Hercynian (Variscan) orogenic belt indicate that most of the crust in Central Europe was first formed during the Cadomian orogeny which straddles the Precambrian–Cambrian boundary. Zircons, however, have a memory of older ages which correspond with those of events known in Fennoscandia. The new radiometrie data are consistent with the stratigraphie record in that they do not provide any evidence for a major early Palaeozoic tectonothermal event between the Cadomian and Hercynian orogenies.Granulites from two localities in the Moldanubian zone yield U–Pb zircon ages of 345 ± 5 Ma; discordant zircon data points indicate that the granulite facies metamorphism was not of long duration. Tectonic units containing these high grade rocks were emplaced amongst amphibolite facies rocks during an event of widespread shearing which has been dated at 341 ± 4 Ma on the basis of a lower U–Pb zircon intercept age from one of the sheared gneisses and 338 ± 3 Ma U–Pb ages from monazites. Rb–Sr muscovite ages of 331 ± 5 Ma from pegmatites axial planar to asymmetrical folds date the last stage of SE-directed simple shear. A Rb–Sr whole-rock isochron of 331 ± 4 Ma from a principal magmatic type of the Central Bohemian pluton confirms the field evidence that the large NE-trending plutons of the Moldanubian zone were emplaced during a late stage of the deformation. The strong disturbance of the U–Pb zircon isotopic system in the sheared gneisses suggests U loss while a high U/Th ratio in monazite from one of these tectonised rocks suggests the simultaneous passage of hydrothermal fluids. Thus a crustal source is indicated for the uranium deposits of the Moldanubian zone.Critical to any plate tectonic model for the development of the Middle European Hercynides was the existence of an ocean in Early Devonian times which separated a North European continent from a South European continent(s). The northward movement of the South European continent over a shallowly-dipping subduction zone and subsequent continental collision can explain the high T–low P metamorphism and the imbricated tectonic style of the Moldanubian zone and adjacent Moravo-Silesian zone along the southeastern Hercynian foreland. The temporal separation of granulites and granites implies distinct conditions of formation and it has been suggested that the plutonism, following on from the imbrication of the Cadomian crust, was initiated by the subduction of wet oceanic sediments.

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The Lis ˇov Granulite Massif differs from neighbouring granulite bodies in the Moldanubian Zone of southern Bohemia (Czech Republic) in including a higher proportion of intermediate-mafic and orthopyroxene-bearing rocks, associated with spinel peridotites but lacking eclogites. In addition to dominantly felsic garnet granulites, other major rock types include quartz dioritic two-pyroxene granulites, tonalitic granulites and charnockites. Minor bodies of high-pressure layered gabbroic garnet granulites and spinel peridotites represent tectonically incorporated foreign elements. The protoliths of the mafic-intermediate granulites (quartz-dioritic and tonalitic) crystallized $360-370 Ma ago, as indicated by laser ablation inductively coupled plasma mass spectrometry U-Pb ages of abundant zircons with well-preserved magmatic zoning. Strongly metamorphically recrystallized zircons give ages of 330-340 Ma, similar to those of other Moldanubian granulites. For the overwhelming majority of the Lis ˇov granulites peak metamorphic conditions probably did not exceed 800-900 C at 4-5 kbar; the equilibration temperature of the pyroxene granulites was 670-770 C. This is in sharp contrast to conditions of adjacent contemporaneous Moldanubian granulites, which are characterized by a distinct HP-HT signature. The mafic-intermediate Lis ˇov granulites are thought to have originated during Vise ´an metamorphic overprinting of metaluminous, medium-K calc-alkaline plutonic rocks that formed the mid-crustal root of a Late Devonian magmatic arc. The protolith resembled contemporaneous calc-alkaline intrusions in the European Variscan Belt.

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The high-pressure granulites from the Bìstvina body contain a mineral association garnet-kyanite-biotite-plagioclase-K-feldspar-quartz ± antiperthite. Based on petrology, as well as major-and trace-element whole-rock geochemistry, the studied eight samples can be subdivided into four types: (1) metamorphosed greywacke, (2) felsic granulite with a low CaO/Na 2 O and K 2 O/Na 2 O ratio (type I), (3) felsic granulite of leucogranitic composition (type II), and (4) kyanite-garnet-biotite migmatitic gneiss. These rocks are associated with minor garnet peridotite and a crustal eclogite with a prograde metamorphic record, as described in the literature. Garnet in the quartz-feldspathic rocks typically contains 2435 mol. % Prp and 514 mol. % Grs components with Ca zoning across grains. Using compositions of garnet cores and the associated plagioclase and biotite, the geothermobarometric calculations prove the equilibration under eclogite facies conditions (P = 1.8 2.2 GPa and T = 800920 °C). Two of the samples important for thermobarometry (felsic granulites type I and II) are free of antiperthite. The associated Ky-Grt-Bt migmatitic gneiss recording conditions near 1.4 GPa and 670 °C may represent a foreign component in the Bìstvina granulite body. Although one meta-greywacke sample shows incipient replacement of garnet by biotite + plagioclase, the other samples are free of a decompression recrystallization record. Thus the granulites of the Bìstvina body stand in sharp contrast to the better known granulites in the Moldanubian Zone, by their lack of evidence for an extensive decompression recrystallization.