Single-well seismic imaging using the full waveform of an acoustic sonic

Louis Chabot, David C. Henley, R. James Brown, John C. Bancroft

The reservoir characteristics around the borehole play an important role in determining the success or the failure of a well. However the knowledge of such reservoir characteristics is not always complete. This work seeks to fill that gap by attempting to image scattered energy beyond the borehole wall. The imaging of that scattered energy is to be achieved by single-well seismic imaging using the full waveform acquired with a standard sonic well-logging tool. In the first part of this paper, a synthetic acoustic full-waveform sonic dataset is created on which a proposed processing flow is applied. The proposed processing flow successfully imaged a scatter point. In the second part of this paper another processing flow is proposed this time to image scattered energy beyond the borehole wall using real full waveform field data. The image obtained shows promising indications of some dipping features, which are expected because of the inclination of the borehole with respect to the geological formations. However, the weakness of the reflections could be explained by a number of things, such as incompletely cancelled noise modes. Further work is thus required to improve on the two proposed processing flows.