Facies characteristics and reservoir properties of the Paleocene carbonates (Çaldağ Formation) in the Tuz Gölü Basin, Central Anatolia, Turkey

• Çaldağ Formation units were modelled.
• Reservoir rock properties and quality were evaluated.

The Tuz Gölü Basin is one of the largest interior petroleum exploration basins in the Central Anatolian, Turkey, composed of mainly Upper Cretaceous to Tertiary shallow water carbonates and siliciclastics. Çaldağ Formation is composed of mainly carbonates, siliciclastic, lacustrine carbonate that are outcropped in limited areas to the east (Paleocene) and west of the basin (Late Paleocene), and also penetrated in a well. They can be also found as gravels and large blocks in the Upper Paleocene to Middle Eocene units to east of the basin. The Formation were probably deposited in an environment where tectonic was active under the control of the paleo-topography, substratum type and sea level changes. Outcropped carbonates are dominantly in the packstone–wackestone facies including boundstone compositions, and having minor intergranular porosity, fracture and stylolitation (0.10% to 3.67% and 0.01 to 4.10 mD). Carbonate and secondarily iron oxide cementation has played a significant role reducing porosity and pore space. However, the well log data indicate that they are composed of limestone, dolomite and sandstone that could bear a moderate to good reservoir rock potential intervals based on porosity values (between 2.5 and 24.5%). Stratigraphic position and sedimentological properties indicate that the outcropped and penetrated carbonates by well could not be evaluated as autochthonous at the east of the basin. Our results suggest that possibility of the Paleocene unites reservoir potential is questionable in the Tuz Gölü Basin.