Diffraction Imaging: Tackling Challenges in the Current Imaging of Complex Carbonate Environments

Abstract

The authors hereby propose diffraction imaging as a tool to de-risk small-scale features, as those related to a fractured carbonate reservoir. Diffraction imaging has indeed increasingly generated interest as a method for the detection and delineation of small-scale (less than the wave length) subsurface elements such as faults, pinchouts, karsts, fracture corridors, injectites, etc. These elements cause sharp changes/contrasts in the subsurface physical properties and geometry, and they are generic sources that scattered/diffracted seismic energy (Landa 2012). The diffracted energy carries however much lower intensity than the reflected one and this fact hinders the confident identification and delineation of the small-scale objects with standard methodologies. Therefore, the main aspect in diffraction imaging is the accurate separation of the diffracted and reflected components of the total wave field. Such separation can be performed efficiently in the structural dip-angle domain (Landa et al. 2008). In this study we present examples of diffraction imaging and interpretation for carbonate reservoirs. The results achieved show the high resolution and reliability of the proposed methodology.