Multistage geochronological evolution of the Velká Fatra Mountains—a combined TIMS and ion-microprobe study on zircons

Abstract

New isotopic and geochronological data from the Velká Fatra Mountains (Tatric Unit of the Central Western Carpathians) are presented and discussed with a focus on the Variscan orogeny and events during Permian and Early Triassic times. The investigated samples are meta- to per-aluminous granitoids and their trace element patterns indicate a volcanic arc origin. This study presents U–Pb single zircon data, measured on TIMS as well as on an ion-microprobe (SIMS). The zircon age determinations were additionally constrained by cathodoluminescence (CL). Most of the investigated granitoids yield Variscan emplacement ages of about 310 Ma. However, for the Lubochna leucogranite a Triassic crystallisation age at 231±17 Ma was found. The presence of such young, slightly discordant zircon ages gives evidence for a so far unknown Late Permian–Early Triassic magmatic event in the Western Carpathians.