Investigation of recharge-discharge relationship in Çokrağan (Banaz-Uşak) karst system

The aim of this thesis study is to examine the recharge-circulation-storage-discharge relationship of the Çokrağan Karst System (CKS) which is located in the east of the Gediz Basin and in the northwest of the Banaz district of Uşak province. The CKS has an approximate surface drainage area of 10.7 km2 and it is discharged from the Jurassic Çiçeklikaya Formation with a long-term average monthly flow rate of 0.349 m3/year. In order to elaborated the morphology-hydrogeology relationship within the study area, a hydrogeological conceptual model was developed by evaluating the physical parameters such as geology, tectonism and morphology, and dynamic properties such as precipitation regime, evaporation, infiltration, recharge, flow and storage. According to the water chemistry analyses results obtained during this study, the dominant major cation and anion are Ca and HCO3, respectively. The evaluation of the water budget studies along with the hydrogeological conceptual model of the CKS revealed out that the Ekinlik Basin is recharged from the Fındıklı Basin. When the spring recession analysis of the Çokrağan Spring flows carried out by using flow observation data between 1980-2020, both the high coefficient of variation observed in the discharges and the shape of the hydrographs as well as the variation in the spring recession coefficient indicate that storage and flow in the CKS occur along well-developed fracture systems and karstic channels. It was concluded that CKS is a highly anisotropic and heterogeneous media with relatively high hydraulic conductivity and transmissibility and a relatively low storage coefficient.