Carpathian Journal of Earth and Environmental Sciences

Upper Cretaceous sedimentary deposits from southern part of the Apuseni Mountains are of a special importance in constraining the tectonic evolution of this region. Therefore, the Upper Cretaceous units within this region, such as Bozeş Formation, have to be properly described in terms of provenance and basinal evolution. This study represents the first extensive investigation of heavy mineral assemblages of siliciclastic rocks from Upper Cretaceous Bozeş Formation, in order to constrain their source types. The heavy mineral analysis implies identification of mineral species, but also the description of the crystal habitus. The associations are similar in all studied samples and consist mainly of moderate rounded grains of garnet, zircon, epidote, tourmaline, rutile and titanite. Two main, contrasting sources are deciphered on the base of heavy mineral analysis. These are represented by a low to medium metamorphic unit, and an older sedimentary succession, with smaller contributions from acid igneous rocks.