Chert blocks in the ophiolitic mélange of Zlatibor Mt. (SW Serbia): Age and geodynamic implications

Cherts are quite frequently occurring rocks in the Internal Dinarides, an extremely complex area composed of several tectonostratigraphic units in which oceanic sediments, ophiolites and partly metamorphosed parts of the distal continental margin of Adria are preserved. Therefore, these cherts differ in age and the original depositional environment in which they were formed. Results of investigations carried out in the chert blocks found in the mélange in the vicinity of Jasenovo village on SE slopes of Zlatibor Mt. are presented here. Radiolarian cherts from the studied localities represent blocks in mélange of the East-Bosnian–Durmitor Unit, exposed in a large tectonic window below the Triassic carbonates of Drina–Ivanjica Unit. Biostratigraphic data revealed Callovian–early Kimmeridgian ages of the studied chert blocks, thus implying a Kimmeridgian or younger age of obduction of the West Vardar ophiolites.