Geochronological and geochemical characteristics of zircon from lower cretaceous pegmatites of the Pelagonian Unit, N. Macedonia

Modern interpretations of the geological evolution of the Balkan terranes consider the Jadar Kopaonik block and the Pelagonian unit as the most distal continental fragments of the Adriatic plate margin. These tectonic units are predominantly composed of Paleozoic sequences, while their upper parts have been eroded due to tectonic exhumation. They mainly consist of Precambrian and Paleozoic
complexes overlain by Triassic and Jurassic carbonates, which are thrust and imbricated within a system
of west-vergent nappes west of the Vardar zone sensu stricto.
The Pelagonian massif is approximately 420 km long and about 60 km wide, extending in a NNW SSE direction, and represents part of the central Hellenides. According to modern interpretations, this tectonic unit is equivalent to the Drina-Ivanjica composite unit of the Dinarides. The Pelagonian mas sif is the largest unit within the central Hellenide belt. It is located between the Vardar zone and the Di naride (West Vardar) ophiolite belt, across the territories of North Macedonia and Greece (Florina
terrane). High-grade metamorphic rocks (amphibolite facies with eclogite relics) can be subdivided into two complexes: a lower complex composed of biotite and two-mica gneisses, amphibolites, horn blende and epidote-hornblende gneisses, leucocratic gneisses, migmatites, and orthogneisses; and an
upper complex consisting of gneisses, micaschists, amphibolites, schists, and massive marbles (e.g.,
Sivec marbles).
Our study focuses on the age and geochemical characteristics of zircon from pegmatites in Alinci and Čanište, where Lower Cretaceous zircon ages have been documented for the first time. The results indicate significant magmatic activity during the Lower Cretaceous, geochemically corresponding to S type granitoid magmatism. These findings are consistent with previous studies of granitoid magmatism
and migmatites in the Pelagonian unit of Greece. Our results suggest that the Pelagonian massif most likely represents an exotic continental block that collided with the European plate during the Lower Cretaceous, and that it does not form part of a single coherent belt with either the Jadar-Kopaonik or the Drina-Ivanjica units, as being discussed more recently.