Modification of Winland Rock Typing Based on Reservoir Quality and Production Parameters in Carbonate Rocks

The high heterogeneity in carbonate rocks makes it impossible to relate reservoir and production parameters to the rock properties and generalize it to the reservoir. Hence, in order to reduce diversity, different rock types have been created based on various factors such as lithological parameters, porosity, and petrophysical properties. Fluid flow parameters are not adequately addressed in these classifications, and some of these rock classifications are overly complex, rendering them challenging to utilize. Considering the features of fluid flow in classification, utilizing minimal data input can have a major impact on carbonate rock studies. In this study, the focus of investigation is on analyzing the reservoir quality of Winland throat radius rock typing, while also exploring fluid flow parameters as production and dynamic parameters. In this regard, using the petrophysical data of 779 carbonate rock samples from the Ilam, Sarvak and Fahliyan formations, the Winland rock typing was determined, and then the appropriateness of the rock typing was investigated using lithological, petrophysical, pore and dynamic parameters. Investigations showed that by correcting the boundaries of the Winland rock typing, regular connections are established with the mentioned parameters. The results showed that although the reservoir properties show improvement with the increase in the group number, the dynamic properties do not follow this trend. Overall, the middle groups are the most desirable part of the rock typing in terms of reservoir quality and production parameters. The shift of static rock typing towards dynamic rock typing and also the use of the ratio of recovery factor to irreducible water saturation are as a key parameters to check production quality which are recommended.