3D visualisation of AVO anomalies
Anat Canning, Alex Litvin and Lucy Eastwood of geoscience software and services company Paradigm Geophysical make the case for multi-attribute visualization techniques in the analysis of large AVO data sets claiming faster detection of hydrocarbon anomalies. AVO inversion of 3D data leads to generation of multiple volume attributes. In the case of Shuey-Hilterman formulation Intercept and Gradient volumes are generated. In the case of Aki-Richards formulation the inversion process generates P and S wave reflectivity volumes. In addition to these primary attributes a number of secondary attributes are generated (For example: Constrained gradient, pseudo-Poisson reflectivity, Fluid factor etc.). For confident identification of AVO anomalies the interpreter has to work simultaneously with these multiple 3D attribute volumes. This is an inherent difference between the interpretation of conventional seismic cubes and the interpretation of 3D AVO data. In this paper we will present two approaches to combined visualisation of 3D AVO attributes generated by the application of Shuey-Hilterman inversion scheme to the 3D pre-stack time migrated data set from the North Sea. The first approach uses multi-attribute volume visualisation of AVO attributes. The second approach uses cross-plot based volume visualisation.