On the graptolite schist's formation, Silurian-Lower Devonian, in the Carpatho-Balkanides of eastern Serbia

Abstract

The fabric of the Silurian and a part of the Lower Devonian in the Carpatho-Balkanides of eastern Serbia, i.e. in two large geotectonic units, the Kučaj Unit (Getic) and the Luznica Unit (West Kraishte), is reviewed in this paper. Silurian sediments of the Serbian part of the Carpatho-Balkanides are made of the Graptolite Schists Formation, from the lower part of the acuminatus Zone at the Ordovician-Silurian boundary to the transgrediens Zone at the Silurian-Devonian boundary. The presence of all parts of the Silurian is proved on the basis of graptolite faunas: Llandovery (Rhuddnanian, Aeronian, Telychian), Wenlock (Sheinwoodian, Homerian), Ludlow (Gorstian, Ludfordian) and Pridoli. Two Lower Devonian (Lochkovian) zones (uniformis and hercynicus), with which the deposition of the Graptolite Schists Formation ended in eastern Serbia is also described. Data on the geochemical characteristics of the Graptolite Schists Formation are presented as well.