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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.

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Multidisciplinary research evaluates structural, metamorphic and petrochemical data of selected rock types in different units located in the northeastern part of the Bohemian Massif, Czech Republic: (1) the Strážek Unit in the northeastern part of the Moldanubian Zone, (2) the Svratka and Kutná Hora units correlated with the Orlice-Sněžník Unit in Western Sudetes as well as (3) the Polička, Hlinsko and Zábřeh units belonging to the Teplá-Barrandian Zone. Petrochemical data for metasediments of the Polička, Hlinsko and Zábřeh units are mutually comparable and confirm a lithological affinity to the upper-crustal Teplá-Barrandian Zone. The FeO t /MnO ratios in metasediments of the Strážek Unit and the Svratka Unit indicate differences in the origin of sedimentary protolith rocks. Relict pre-Variscan structures, including extensive migmatization, and high-grade mineral assemblages with peak metamorphic pressures of ~1.4 GPa in skarn bodies, are preserved in the Svratka Unit. The evidence for Palaeo-Variscan (390-355 Ma) HP and UHP events, recorded in the high-grade Kutná Hora and Orlice-Sněžník units, was observed neither in the NE part of the Moldanubian Zone (Strážek Unit) nor the Teplá-Barrandian Zone (Polička and Zábřeh units). The Variscan orogenic event imprinted in the Svratka, Polička and Zábřeh units was the right-lateral slip along WNW-ESE trending shear zones. This deformation was accompanied by metamorphism at ~580-650 °C and ~0.5-0.7 GPa (352-343 Ma) and intrusion of numerous small bodies of syn-deformation calc-alkaline granitoids in the Polička and Zábřeh units. The younger metamorphic fabrics in the northeastern part of the Moldanubian Zone reflect a fast exhumation of deep-seated high-grade complexes at ~340 Ma, which was constrained by post-tectonic emplacement of durbachites at ~339 Ma. Metamorphic development in felsic granulites of the Strážek Unit, metamorphosed c. 340 Ma ago at 850 °C and 1.8 GPa, was followed by decompression to T ≅ 790 °C and P = 1.3 GPa and finally T = 700 °C and P = ~0.4 GPa. In contrast, Běst-vina granulite in the Kutná Hora Unit, with the ~360 Ma high-grade metamorphism at 800-920 °C and 1.8-2.1 GPa, is free of such a HT-LP overprint. Thus the data indicate that the Svratka and Kutná Hora units, exhibiting numerous mutual differences, should not be considered as belonging to the Moldanubian Zone as they evolved as independent entities. The geochemical data on garnet-clinopyroxene skarns from the Moldanubian Zone, the Svratka and Kutná Hora units do not provide mutually distinguishing features. This is largely due to a very wide compositional variation in rocks interpreted as metamorphosed exhalite with detrital material admixture. Skarns from the Svratka Unit preserve clinopyroxenes with elevated jadeite component (0.5-24 mol. %) and prograde compositional zoning in garnet -features obliterated in samples from the Moldanubian Zone and the Kutná Hora Unit.