Understanding frequency decomposition colour blends using forward modelling — examples from the Scarborough gas field

Abstract

Frequency Decomposition (FD) colour blending of 3D seismic data has become a mainstream technique used by oil and gas industry G&G specialists for imaging subsurface geology. The workflow involves creating frequency band-restricted components of the seismic data and blending these together into a single volume, typically using a three-dimensional, red-green-blue (RGB) colour scheme. The blends often produce high-resolution, detailed images capable of detecting very subtle features owing to the interference between three frequency band components which tune at different frequencies. A major advantage is being able to assess distribution and extrapolation of results away from well locations since the results are volumetric and not restricted to a well location. The workflow has typically been applied in a qualitative manner to identify depositional features, structures and geomorphologies visually based on colour changes in the blends. However, the link between the colours and rock physics is poorly understood.