engleski

Neogene marine mammals from Vranić sand deposit

The Neogene formations of the marginal parts of the Pannonian Basin in Croatia include numerous quartz sand deposits. One of them is Vranić at the foothills of Papuk Mt. During the initial evolution of Pannonian Basin weathering conditions led to erosion of exposed granites, transportation of terrigenous material and deposition of quartz/feldspar fractions grains. The deposition of quartz during the Miocene and Pliocene was cyclic. Cyclicity was induced by the regional tectonic events and repeated transgressions and regressions accompanied by intense weathering of exposed rocks (PAVELIĆ, 2001). This weathering occurred under moderately warm and humid climatic conditions (BAKRAČ, 2005). Vranić is a sand quarry 300 m long and 30 m thick. Sedimentology of Vranić has been previously described as a sand deposit in which sand was transported from nearby mountains. In this research we have collected 8 samples for sedimentological analysis. Seven of them are from sand material and one is from marl lens at the middle part of the deposit. Marl sample has been analysed on pollen content. Grain size analysis proved that coarse sand is dominant fraction (range of 38-97% depending of the sample). SEM images of quartz grains provide detailed insight of shape and textures of the sand. Grains are dominantly angular and subangular. A few of them are sub rounded. This confirms a theory of short transport from nearby mountains. Osteological material sampled at Vranić consisted of 78 fossilized bones and teeth and 81 fossilized bone fragment originating from fishes (Class: Pisces) and mammals (Class: Mammalia). Out of the total sample 14 bones and 1 tooth originated from whales (Class: Mammalia, Ordo: Cetacea). The cetacean sample consisted of 5 humeri, 1 radius, 3 ulnas, 1 phalanx, 2 vertebrae, 1 tympanic temporal bone and 1 petrous temporal bone. According to our preliminary study Vranić represents a valuable finding of cetacean fossil remains and could serve as an important data source about marine life in Central Paratethys. Both sedimentological and palaeontological results suggest that sand and fossil material were redeposited in short transport in aqueous environment.

Vranić, sand deposits, neogene, mammals, Cetacea

nije evidentirano