Investigation of the geology and sinkhole risk of the southern area of Egribayat neighborhood (Selcuklu, Konya)

The study area is located approximately 37 km north of Konya city center. In terms of neotectonic setting, the region lies within the Central Anatolian Plains Region and the Konya–Eskişehir Neotectonic Zone. The main geological unit in the study area is the Lorasdağı Formation, which generally consists of light gray, beige, and whitish, thick- to medium-bedded limestones that are locally oolitic and algal, containing carbonate materials. Overlying this formation with an angular unconformity is the Divanlar Formation. This formation comprises fan deposits that are semi-consolidated, carbonate-bearing, mud-supported sands, gravels, and occasional blocks. It mainly consists of tightly cemented, poorly bedded, clast-supported conglomerates with angular gravels derived entirely from the Loras Formation. Additionally, the Divanlar Formation occurs as clastic deposits accumulated along fault scarps and plains. Within the regional fault zone, multiple synthetic and antithetic faults are present. These faults can suspend the clastic deposits belonging to the Divanlar Formation, resulting in lens-shaped, coarse-grained gravel units observed at different levels. The Konya depression basin is bounded by the Konya Fault Zone (KOFZ) to the west, the Karaömerler Fault to the north, and the Divanlar and Göçü faults to the east. Sinkhole formations are observed within these units in the region. Moreover, the presence of highly karstic Mesozoic carbonates at the base of the younger sediments is a significant factor in evaluating the region's sinkhole potential. Therefore, the aim of this thesis is to investigate the sinkhole potential and subsurface risks of the area. Within the scope of the study, geological and geophysical methods such as ERT (Electrical Resistivity Tomography), drilling, microtremor, and MASW (Multichannel Analysis of Surface Waves) were applied. As a result of these studies, possible subsurface risks (such as faults, voids, fractures, and formation transitions) were identified, and recommendations were provided for risk mitigation and remediation.