Application of Curvature Attributes in Prediction of a Carbonate Reservoir

Seismic curvature attributes, as being second-order derivatives of seismic information, allow interpreters easily to map the structural deformation and subtle stratigraphic details that are not readily observable through seismic data or first-order derivatives such as the dip magnitude and the dip-azimuth attributes. The conventional computation of curvature measures may be termed as structural curvature, generated from lateral second-order derivatives of time-structure component of seismic data, and provides the information related to time structure. Likewise, amplitude curvature, as being lateral second-order derivatives of amplitude component of seismic data, contains the information about lateral change of seismic amplitude. In this paper, we apply the most-positive and most-negative amplitude curvature measures to characterize a carbonate reservoir in Tarim Basin, NW China through computing the first order derivatives of the inline and crossline components of the energy-weighted amplitude gradients. The most-positive amplitude curvature measure is very effective to represent the internal features of the channels and fractural-vuggy systems, while the most-negative amplitude curvature highlights the lineament details near the edges of the channels and fractural-vuggy systems. In addition, application of multispectral amplitude curvature computation to prediction of the carbonate reservoir shows that the long-wavelength amplitude curvature attributes depict the larger scale geological features as compared with the short-wavelength amplitude curvature measures which focus on the local details. In brief, integrated application of long- and short-wavelength computation of most-positive and most-negative amplitude curvature attributes exhibits the characteristics of the carbonate reservoir from different sides.