Tectonic geomorphology and paleoseismological characteristics of the Nifdağı segment in the Eastern Part of Izmir

This thesis aims to reveal the tectonic geomorphology and paleoseismological characteristics of the Nif Dağı segment, located on the southwestern margin of the Gediz Graben and previously not examined in detail. The study was carried out within the scope of the 2024 activities of the Türkiye Paleoseismology Research Project (TÜRKPAP), coordinated by the General Directorate of Mineral Research and Exploration (MTA) of the Republic of Türkiye. The segment, approximately 13 km in length, is characterized by right-lateral strike-slip motion and extends along a fault plane dipping 65–70° SE. Along this strike, tectonic geomorphological structures such as fault scarps and fault facets are observed, and particularly between the villages of Karacaağaç and Kırıklar, a pressure ridge formed by fault stepping has been documented. Morphological indicators such as fault-controlled drainage networks and the truncation of fluvial fans have also been identified along the segment. In two trench excavations opened in Karacaağaç Village, faulting evidence such as stratigraphic discontinuities, the fault plane, a crushed zone, and flower structure was observed. Based on the OSL dating results obtained from the Karacaağaç trench, an earthquake was detected in the Late Pleistocene (15 ± 1 ka). In the Meşelik trench, an earthquake that produced a surface rupture in the Late Holocene (3 ± 1 ka) was identified. In the study, kinematic solutions were generated using the FaultKin software, and microtopography, LIDAR, and remote sensing data were evaluated with ArcGIS, SAGA GIS, and CorelDRAW. It has been determined that the segment poses a significant earthquake hazard for the residential and industrial areas of İzmir and its surroundings.