Effective workflow of Poisson impedance analysis for identifying oil reservoir with similar resistivity log response to neighboring medias

Abstract

PI is an effective indicator for oil reservoir and defined as the difference between acoustic impedance and scaled shear impedance. To estimate the scale factor ‘c', TCCA (Target Correlation Coefficient Analysis) method has been widely used. However, when the resistive log of the oil reservoir shows similar trend to those of neighboring medias because of its high porosity, PI analysis based on TCCA method can lead to misinterpretation. To overcome this problem, we propose more effective PI analysis workflow which consists of three steps: lithology impedance (LI), porosity impedance (Ø I) and fluid impedance (FI). We could successfully identify the oil reservoir with high porosity by using the proposed PI analysis workflow and real well log data. This result implies that the proposed workflow of PI analysis can be used to effectively identify the potential oil reservoirs from seismic data.