Tech Trends Attributes Improve 3-D Interpretation Advanced volumetric attributes such as reflector convergence and reflector rotation about the normal to the reflector dip hold promise in interpreting angular unconformities and determining the rotation of fault blocks across wrench faults and other discontinuities. Such attributes can facilitate and quantify applying seismic stratigraphic workflows to large 3-D seismic volumes. By Satinder Chopra and Kurt J. Marfurt CALGARY-Coherence, curvature and other geometric attributes are useful for delineating a subset of seismic stratigraphic features such as shale dewatering polygons, injectites, collapse features, mass transport complexes and overbank deposits, but they have limited value in imaging classic seismic stratigraphy features such as onlap, progradation and erosional truncation. In this context, advanced volumetric attributes such as reflector convergence and reflector rotation about the normal to the reflector dip seem to hold promise. While the reflector convergence attribute is useful in interpreting angular unconformities, the reflector rotation about the normal attribute determines the rotation of fault blocks across wrench faults and other discontinuities. Such attributes can facilitate and quantify using seismic stratigraphic workflows to large 3-D seismic volumes. Another attribute that is useful in interpreting seismic data is the Euler curvature. This attribute is helpful in interpreting lineament features in desired azimuthal directions. It can be run on the final migrated stacked volume to obtain the attributes in different azimuthal directions and does not require azimuth-limited prestack migration. 126 THE AMERICAN OIL & GAS REPORTER