This paper summarizes the current knowledge on the nature, kinematics and timing of movement along major tectonic boundaries in the Bohemian Massif and demonstrates how the Variscan plutonism and deformation evolved in space and time. Four main episodes are recognized: (1) Late Devonian–early Carboniferous subduction and continental underthrusting of the Saxothuringian Unit beneath the Teplá–Barrandian Unit resulted in the orogen-perpendicular shortening and growth of an inboard magmatic arc during c. 354–346 Ma; (2) the subduction-driven shortening was replaced by collapse of the Teplá–Barrandian upper crust, exhumation of the high-grade (Moldanubian) core of the orogen at c. 346–337 Ma and by dextral strike-slip along orogen-perpendicular NW–SE shear zones; (3) following closure of a Rhenohercynian Ocean basin, the Brunia microplate was underthrust beneath the eastern flank of the Saxothuringian/Teplá–Barrandian/Moldanubian ‘assemblage’; this process commenced at c. 346 Ma in the NE and ceased at c. 335 Ma in the SW; and (4) late readjustments within the amalgamated Bohemian Massif included crustal exhumation and mainly S-type granite plutonism along the edge of the Brunia indentor at c. 330–327 Ma, and peripheral tectonothermal activity driven by strike-slip faulting and possibly mantle delamination around the consolidated Bohemian Massif's interior until late Carboniferous–earliest Permian times.

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.

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In this paper are reviewed structural, petrological and geochronological data from the main units at the NE periphery of the Moldanubian Zone, i.e. Kutná Hora Complex, Svratka Unit, Polička and Zábřeh units, as well as the Strážek Unit of the Moldanubian Zone. In this domain of the Bohemian Massif, the lower-and upper-crustal units are dominated by metamorphic fabrics produced during the Variscan orogeny. The mid-to upper-crustal Svratka, Polička and Zábřeh units are affected by ~MP/MT "long-lived" (~350-339 Ma) tectonometamorphic event reflecting ~WNW-ESE right-lateral strike-slip shearing (transpressional to transtensional tectonics). These regional fabrics are in the Polička and Zábřeh units related with syn-tectonic emplacement and crystallization of calc-alkaline intrusions (Zábřeh Intrusive Complex, Miřetín nad Budislav plutons). In the three structurally high units in the Kutná Hora Complex, Orlice-Sněžník and the Strážek units the strike-slip, "long-lived" tectonics is rather localized; the high-pressure, high-temperature events followed by heterogeneous and polyphase exhumation of deep-seated rocks to mid-crustal levels are preserved. Ultrapotassic rocks (durbachites) of the Strážek Unit, dated at ~339 Ma, intruded posttectonicaly.