Lithology Impedance Attribute to Identify LRLC Zone Based on Well Log

This paper describe about the characterization of Low Resistivity Low Contrast (LRLC) reservoirs. Using P-Impedance (Ip), S- Impedance (Is) and Poisson Impedance (Ip-C*Is), discrimination of reservoir facies was effectively done from background non reservoir facies. Poisson's ratio and density are important in reservoir facies delineation. When the hydrocarbon bearing LRLC zones impedance contrast is very small from background trend, Poisson Impedance (PI) curve is correlated with the Gamma Ray (GR) for different values of c and it is possible to determine the maximum correlation coefficient in each case. The c value corresponding to the Maximum correlation coefficient for GR is used to compute another attribute that would emphasize lithology called lithology Impedance (LI). We can characterize these LRLC zone by cross-plotting Lithology Impedance with GR log.