Hebron / Ben Nevis rock property analysis and modelling study
Andrew John Royle, John D. Logel, Laurence R. Lines
ABSTRACT This paper investigates the sensitivity in amplitude variation with offset (AVO) behaviour with varying rock properties in an attempt to predict oil gravity (density) contrasts. Rock physics scenarios associated with Ben Nevis reservoir zone are performed using Biot-Gassmann fluid replacement modelling to vary porosity, water saturation, and oil density (API). Since, there are numerous variations of these rock properties, AVO modelling volumes are utilized to analyze and interpret the results. Prior to modelling, rock property relationships are observed and used in the AVO modelling analysis. Intercept and gradient volumes were extracted from the data and show variations associated with the rock property models. Crossplots of the intercept and gradient are used to further discriminate the input models. Relationships were observed between the variations in water saturation, porosity, and oil density. Three-parameter AVO techniques are also applied to the volumes in an attempt to predict density variations in the pore fluids.