S Gholinezhad - Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
M.R Masihi - Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran

The prediction of porosity is achieved by using available core and log data; however, the estimationof permeability is limited to the scare core data. Hence, porosity and saturation data through theframework of flow units can be used to make an estimation of reservoir permeability. The purposeof this study is to predict the permeability of a carbonate gas reservoir by using physical-basedempirical dependence on porosity and other reservoir rock properties. It is emphasized that this newrelationship has a theoretical background and is based on molecular theories. It is found out that ifrock samples with different types are separated properly and samples with similar fluid-flowproperties are classified in the same group, then this leads to finding an appropriatepermeability/porosity relationship. In particular, the concept of hydraulic flow units (HFU) is usedto characterize different rock types. This leads to a new physical-based permeability/porosityrelationship that has two regression constants which are determined from the HFU method. Thesecoefficients, which are obtained for several rock types in this study, may not be applicable to othercarbonate rocks; but, by using the general form of the model presented here, based on the HFUmethod, one may obtain the value of these coefficients for any carbonate rock types. Finally, weused the data of cored wells for the validation of the permeability results.

Permeability, Porosity, Irreducible Water Saturation, Hydraulic Flow Units, Regression