Single-well imaging using full waveform sonic data

The sonic-waveform processing and imaging flow presented in this paper uses fullwaveform data recorded with a conventional acoustic well-logging tool, then adapts known surface-seismic processing steps and optimizes them for the borehole environment. This paper presents improvements brought to our original sonic-waveform processing and imaging flow. These improvements are better geometry assignment, better noise attenuation, better data enhancement, and the application of prestack time migration with improved parameters. The new flow is tested on a portion of a full-waveform sonic dataset, recorded over a section of the 8-8-23-23W4 well, Blackfoot field, Alberta, intersecting three coal seams at an angle. The upper portion of the composite sonic image showed promising indications of dipping interfaces. However, the targeted three coal seams were not very well imaged in the final composite sonic image. This is probably because of the strong attenuation of the sonic energy by the fractured coal. The composite sonic image shows potentially better resolution than the coinciding surface seismic section. More work is planned to improve further on the demonstrated processing flow.