Mapping multiple attributes to three- and four-component color models — A tutorial

Abstract

During the past 30 years, seismic attributes have evolved beyond simple measures of amplitude, frequency, and phase to include measures of waveform similarity, amplitude variation with offset (AVO), spectral content, and structural deformation. Although neural networks and geostatistics are effective ways of combining the information content of these many attributes, such analyses cannot replicate the pattern-recognition capabilities of an experienced interpreter. For this reason, careful visualization and display of multiple attributes remains one of the most powerful interpretation tools at our disposal. The two most important color display models are based on red, green, and blue (RGB) or hue, lightness, and saturation (HLS). Each of these color models in turn can be modulated by transparency. We recommend using the RGB color model to map attributes of similar type, such as-volumes of near-, mid-, and far-angle amplitude or low-, moder-ate-, and high-frequency spectral components. The HLS model is preferred when one attribute modulates another, such as dip magnitude modulating dip azimuth or amplitude of the peak spectral frequency modulating the phase measured at the peak frequency. Transparency/opacity provides a fourth color dimension and additional attribute modulation capabilities. This tutorial demonstrates those attributes best displayed in each of the two basic color models with examples from the Gulf of Mexico and Fort Worth Basin, Texas, U.S.A. Sometimes these combinations can be achieved using commercial voxel-based interpretation software. By careful use of color and transparency applied to modern volumetric attributes, one can display the strike of faults and flexures in three dimensions, isolate collapse features, and qualitatively display the geomorphology and thickness of channels.