Permeability Prediction for Carbonate Rocks using a Modified Flow Zone Indicator Method

Keywords: Cementation factor, FZI, Hydraulic flow unit, Modified FZI, Permeability prediction


Carbonate reservoir rocks are usually heterogeneous, so it is not an easy task to establish a relation between porosity and permeability in these types of reservoir rocks. First, Kozney and Kozney-carmen formulas were used to establish these relations. Later, the flow zone indicator (FZI) method was introduced, which was widely used to find such a relation since it shows better results than the two former methods. In this work, the classical FZI method and a modified form of the FZI method are utilized to identify the hydraulic flow units and rock quality index to predict permeability. In this FZI method, the cementation factor (m) was introduced in calculating the value of FZI. The data collected from core analysis of the cored intervals in the Tanuma and Khasib formations were used as a database for this work. The classical and the modified FZI methods were applied using the database to predict core permeability. The value of the cementation factor was tuned to get a better match between the predicted permeability resulting from applying the modified method and the measured permeability values. Results show that the correlation coefficients resulting from applying the modified FZI method are closer to unity compared with that resulting from the classical FZI method. Cementation factor (m) of m = 3 for Tanuma formation and m = 3 for Khasib formation are the best values used with the modified FZI method. The modified FZI method shows a regression factor of 0.9986 for Tanuma and 0.9942 for Khasib formation.


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Author Biographies

Ahmed J. Mahmood, Department of Petroleum Engineering, Al-Farabi University College, Baghdad, Iraq

Ahmed J. Mahmood is a Lecturer at the department of petroleum engineering, Al-Farabi University College, Iraq. He got the B.Sc. degree in petroleum engineering, the M.Sc. degree in petroleum engineering (reservoir engineering) and the Ph.D. degree in petroleum engineering from petroleum engineering department, Baghdad University. His researches interest are in numerical simulation, artificial intelligence application in reservoir engineering and rock wettability measurement. Dr. Ahmed is a member of the society of petroleum engineers (SPE) in USA.

Mohammed A. Jubair, Department of Computer Technical Engineering, College of Information Technology, Imam Ja’afar Al-Sadiq University, Al-Muthanna, 66002, Iraq

Mohammad A. Jubair is a lecturer at the department of computer Technical engineering, College of information Technology, Imam Ja’afar Al-Sadiq University, Iraq. He got the B.Sc. degree in computer engineering from Al-Marrif university, Iraq in 2012, the M.Sc. degree from the computer science networks department Kebangsaan Malaysia (UKM) in 2017, and the Ph.D. degree from the faculty of computer science and information technology, University Tun Hussein Onn Malaysia(UTHM)in 2021. His researches interest include software engineering, artificial intelligence, communication systems, networking and machine learning.


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How to Cite
Mahmood, A. J. and Jubair, M. A. (2024) “Permeability Prediction for Carbonate Rocks using a Modified Flow Zone Indicator Method”, ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY, 12(1), pp. 54-60. doi: 10.14500/aro.11314.