3D curvature analysis of seismic waveform and its interpretational implications

In 3D seismic interpretation, curvature analysis has been widely used for structural delineation and fault detection by quantifying the lateral variation of the geometry of seismic reflectors. However, such geometric curvature is limited to the horizontal plane of a seismic survey and thereby utilizes only partial information of the reflection signals. This study extends the 3D curvature analysis to the seismic waveforms in the vertical planes, here denoted as waveform curvature, and investigates the associated interpretational implications. Applications to the F3 seismic dataset over the Netherlands North Sea demonstrate the added values of the proposed waveform curvature analysis in assisting 3D seismic interpretation in three aspects. First, the signed maximum waveform curvature enhances the vertical resolution of the seismic signals on weak reflector identification and interpretation. Second, the signed minimum waveform curvature is closely related to the least waveform variation (or maximum waveform continuity) parallel to a seismic reflector, and thereby the associated azimuth is indicative of the reflector dip. Third, the capability of the curvature operator in differentiating convex and concave bending makes it possible for the decomposition of a seismic image by the reflector types (peaks, troughs and zero-crossings) to facilitate computer-aided horizon interpretation, such as horizon volume extraction.