Sedimentary deposition of Bozeş Formation (Apuseni Mts., Romania) - detrital zircon dating and micropaleontological ages

Abstract

Abstract. In order to establish the age of the Bozeş Formation, which crops out in the SE Apuseni Mts., calcareous nannofossils investigations and U-Pb detrital zircon dating were performed in the Stăuinii Valley section. The results were correlated, and further compared with previous fossil age data. The U-Pb detrital zircon age spectrum reveals a consistent Late Cretaceous grain population, which yielded an age of 83 Ma (concordia age of 82.87±0.59 Ma), interpreted as the maximum deposition age, thus, marking the Early Campanian as the initiation of sediment deposition. Based on the presence of some important taxa in the calcareous nannofossil assemblage, the age of studied section was assigned to Late Santonian? -late Late Campanian.