The geological evolution of the vicinity of the Paşalar excavation area, M. Kemalpaşa-Bursa

Northwest Anatolia has a special importance in terms of the geological evolution of Turkey because there are several suture zones reflecting the occurrence of different oceans between late Palaeozoic-early Tertiary time. These oceans were the Palaeo-Tethys ocean and the Karakaya basin which both closed in Jurassic time, and the Neo-Tethys ocean which closed in late Cretaceous-early Tertiary. Following these events, the neo-tectonic period started. A north-south extension in the early Miocene occurred in western Turkey, and later, in the late Miocene, the North Anatolian Fault formed a diffused strike-slip boundary in northwest Anatolia. The vicinity of the Paşalar excavation area in northwest Anatolia has been mapped and the stratigraphic units described. The Karakaya Complex belongs to the Karakaya basin and is made up of sandstone with limestone, chert and spilite blocks. The Manyas Group relates to the closure of the Neo-Tethys ocean and is made up of marble and schist. The Çataldaǧ Granodiorite probably results from neo-tectonic events. The Deǧirmendere Formation was formed by terrestrial sedimentation and has been affected by more recent tectonic events. The Deǧirmendere Formation has a special importance because of its mammalian fossils. It consists of mainly alluvial and rarely lacustral deposits. Mammals are found in the alluvial deposits. Field observations have illustrated that fossil-rich deposits are located on the marble basement of the Manyas Group, while none have been found on the schist basement. The internal structures of the alluvial deposits have been investigated and it is seen that the material transport direction of the alluvial deposits was from the south to the north around the investigation area.