UIS Commission on Karst Hydrogeology and Speleogenesis
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Karstbase Bibliography Database

Aydin, H.
Investigation of morphology – hydrogeology relations in harmanköy – beyyayla (bilecik, turkey) karst system, phd thesis
Ankara, Turkey
2005

Harmanköy – Beyyayla Karst System (HBKS) forms the highlands in the Central Sakarya Basin. HBKS which is made of Jurassic Bilecik limestone is located within the province boundaries of Bilecik and Eskişehir and extends over a surface area of 49.5 km2. In this study, the HBKS whose boundary conditions are well defined was investigated in terms of morphology – hydrogeology relationships. Within this context, hydrogeological conceptual model of the study area was developed based on the physical parameters such as geology, tectonic, morphology and dynamic properties such as precipitation regime, infiltration, recharge, flow and storage.
Upon the evaluation of morphological, hydrologic, hydrogeological and hydrodynamic properties, it was concluded that HBKS consists of three distinct subsystems, namely the Beyyayla, Döşkaya and Nardın subsystems. It was further determined that Beyyayla and Döşkaya subsystems are similar by the properties mentioned above, while the Nardın subsystem differs from these two subsystems.
Recharge in HBSK occurs in two different forms; allogenic-point and autogenic-diffuse. Surface waters which are drained from Paleozoic age granites located in Beyyayla and Döşkaya subsystems’ recharge these systems as allogenic-point from Beyyayla and Tozman sinkholes. On the other hand, precipitation which falls on the limestone rock-mass supplies the autogenic diffuse recharge to the systems. Recharge to the Nardın subsystem on the other hand, is autogenic diffuse from direct precipitation on to the limestone area. The Qmax/Qmin ratio and the variation coefficient (CV) of chemical compositions of the springs which drain these subsystems, imply that concentrated flow is dominant in all these three systems. In addition, trace experiments carried out in Beyyayla and Döşkaya subsystems suggest that the flow is turbulent and rapid within the well-developed karstic channels. Advective-dispersive transport is controlling the solute transport in the system.
It was speculated that the energy gradient is more important than tectonic, lithologic characteristics and climatic changes in karst evolution Beyyayla and Döşkaya subsystems. Lowering of erosion base caused exposure of granites which consequently supplied the allogenic-point recharge to these subsystems. This was resulted in distinct morphologic, hydrologic and hydrodynamic properties of the subsystem.
Advisor: Assoc. Prof. Dr. Mehmet EKMEKÇİ, Hacettepe University, Department of Geological Engineering, Hydrogeological Engineering Division

Bilecik, Turkey, Harmanköy – Beyyayla Karst System, Morphology, Hydrogeology