Publications

The prediction of lithology and fluid distribution is an important part in reservoir characterization. The aim of reservoir characterization is to explain the physical properties of reservoir rock lithology and fluid content by integrating the geophysics and petrophysical data. In field B, reservoir characterization using acoustic impedance and Lambda-Mu-Rho are not really helpful because of a high degree of ambiguity. Poisson impedance (PI) has been implemented as a solution to address the problem. In essence, Poisson Impedance is rotation of Acoustic Impedance (AI) and Shear Impedance (SI) according to lithology or fluid trend in order to satisfy the equation of PI = AI – cSI. To improve the accuracy of PI calculation, the value of c (optimization factor of rotation) is calculated through the method of TCCA (Target Correlation Coefficient Analysis). Parameters Zp, Zs and density which obtained from the simultaneous inversion then transformed into PI. Our PI models clearly show the separation of rock lithology of hydrocarbon reservoir. Lithology impedance (LI) as a result of the Poisson Impedance-Gamma Ray correlation is able to separate sand and shale very well. Similarly, theFluid Impedance (FI) as a result of Poisson Impedance-Water Saturation correlation is also able to separate the water-bearing sand in the reservoir with high water saturation value relative to gas with a low value of water saturation. By using proven hydrocarbon zone at 2360-2400 m as calibration point,the slicing of Poisson impedance inversion data has provided a clear distribution and interpretation of lithology and fluid content in the reservoir at the field "B" of South Sumatera. Keywords: Reservoir Characterization, Poisson impedance, TCCA, lithology, fluid