The reservoir potential of the Eocene carbonates in the Bolu Basin, West of Turkey

The carbonates of the Tokmaklar Formation have been altered by the following diagenetic processes; micritization, dissolution, fracturing and cementation. As a result of these diagenetic processes, reefal limestones of the Tokmaklar Formation have lost most of their primary porosity. Secondary porosity formed through the dissolution of micritic cement skeletal and non-skeletal (oolitic) grains during early meteoric diagenesis. Oolitic packstone-grainstone facies have moldic porosity, but was probably limited in extent due to a lack of diagenetic pathways. Also in most microfacies fractures tend to be completely filled by sparry calcite. Consequently fractures reduce the porosity of the Tokmaklar limestones.