COMPARATIVE ANALYSIS OF WATER SATURATION AND PAY ESTIMATES USING TRADITIONAL AND NOVEL PETROPHYSICAL METHODS

Abstract

Formation Evaluation is a key discipline for reservoir characterization that feeds most of the reservoirs engineering estimate for reserves in place. Water saturation is one of the most significant petrophysical parameters required for the calculation of hydrocarbon volume. Accurate determination of water saturation is more or less established in cleaner formations using Archie's. However, with inclusion of clays and other heavy minerals, the saturation estimation needs more detailed inputs of lithology and fluid types, including salinity, pressure and temperature. Even though the concepts of pay identification and reserves estimate looks straightforward but it involves lot of deterministic input and subjective assessment of the wiggly logs. In this thesis, I tried to optimize the workflow by standardization of cut-offs or qualifiers of different parameters directly or indirectly involved in calculating the hydrocarbon in place to be more uniform and generalists. To reduce the subjective bias even though we didn‟t have much data but the results on the test well show the good promise in terms of estimating the pore fluid density, porosity, formation water conductivity and in the end saturation using different methods considering the extra conductive clays for estimating net pay determination. I also came up with an automated code to readily detect the wet and other hydrocarbon bearing zones and tested the same in the current well.