International Geological Journal - Official Journal of the Carpathian-Balkan Geological Association

From subduction to collision: Genesis of the Variscan granitic rocks from the Tatric Superunit (Western Carpathians, Slovakia)

Published:

Pages: 96 - 113

DOI: https://doi.org/10.31577/GeolCarp.72.2.2

Authors: MILAN KOHÚT, ALEXANDER N. LARIONOV

Abstract: Granitic rocks from the Core Mountains of the Tatric Superunit (Western Carpathians, Slovakia) were dated by means of the sensitive high-resolution ion microprobe (SHRIMP) zircon U–Th–Pb method. The dated granitic rocks yielded a broad interval of the Concordia ages from 365 ± 5 Ma to 332 ± 3 Ma and largely invalidated the former hypothesis of a duality/antagonism in emplacement ages of the Variscan S- and I-type granites (Mississippian vs. Pennsylvanian) in the Central Western Carpathians (CWC). Generally, the obtained magmatic ages cluster in two separate intervals reflecting different stages of orogeny. The older, Famennian–Tournaisian event (365–350 Ma) was related to subduction of the Rheic Ocean, whereas the younger, mostly Visean event (348–332 Ma) was associated with collisional melting. The Th/U ratios of analysed zircons are compatible mainly with their magmatic origin (Th/U > 0.2), while the lower ones (Th/U 

Keywords: Western Carpathians, Core Mountains, genesis, granitic rocks, SHRIMP dating, zircon

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