Perpustakaan Digital ITB

Difficulty to predict accurately permeability of a carbonate reservoir causes the uncertainty of reservoir characterization. The classic way to get a solution to the problem is done with a single correlation of permeability and porosity based on subjective geological interpretations and the results are often inaccurate. Hence, proper understanding of reservoir rock typing is the key to improve reservoir characterization. A rock type or flow unit is represented by unique permeability- porosity relationship which is imprinted from specific geological processes. In carbonate rock, depositional process and diagenesis control rock’s pore geometri and pore structure. The goal of this study is to obtain ways to overcome permeability estimation problem for uncored zone and/or uncored wells in a carbonate reservoir. The data used are routine core analysis (RCAL) data, special core analysis (SCAL), and geological report. This method consists of rock typing and permeability estimation using the integration of SCAL, routine core data, and geological report. Rock typing is established on the basis of pore structure and geometrical attributes and core descriptions data. The SCAL data are primarily used to obtain irreducible water saturation. Permeability estimation is developed by establishing correlations between permeability, porosity, and irreducible water saturation. Carbonate samples used have permeability ranging from 0.01 - 860 milidarcies. The number of rock samples having routine core analysis is 578 and only 10 sets of SCAL data are available. From this sample, eight rock types are determined eith specific lithofacies and verified by SCAL data. Permeability estimation shows the result close to permeability core.