The Geomorphology of the Lower Basin Yanarsu (Garzan) Stream

In this thesis study, the geomorphological characteristics of the lower basin of Yanarsu (Garzan) Stream which is one of the important tributaries of Dicle River have been investigated. The lower basin of Yanarsu Stream is surrounded by Mereto Mountain in the north, Garzan and Yanarsu Mountains in the south and Kıra Mountain in the west. The mountainous areas are composed of Paleozoic and Mesozoic formations in the north and of Eocene and Oligocene Formations in the south. The plains formed by to the river basins between these two mountainous areas are composed of Upper Miocene-Pliocene fillings. The slightly undulating plains in the easternmost part of the Diyarbakır basin and between Garzan and Yanarsu Mountains in the south and old Garzan Resan Anticline in the north are called Garzan Plain. The plain corresponds to a syncline between the folded structures in the north and south. This syncline is divided into two parts by Yanarsu (Garzan) Stream. With this division, the areas to the west of the Yanarsu Stream have been extremely split off by tributaries. The part remaining in the east is composed of slightly undulating plains which are unweathered compared to the west. The original Garzan Plain corresponds to the slightly wavy plains bounded by the folded structures in the north and south remaining in the east of the Yanarsu Stream. The 10 km wide and 25 km long plain covers an average area of 250 km2 in the NW-SE direction. Garzan Plain developed on the late cover units consisting of Upper Miocene-Pliocene conglomerate, sandstone and claystone lithologies. The basin, which was a sedimentation area during the Upper Miocene-Pliocene, took its present form by opening to external drainage in the Quaternary. This basin where all the structures are seen except for the glacial topography is an open-air museum in terms of geomorphology.