Since recent rediscovery of the role which amplitudes can play in seismic exploration, potential information content in other attributes has been suspected. Attempts to use these attributes have been directed essentially toward special problems (thin beds, fracture porosity) and/or special displays (instantaneous frequency, phase, etc). In fact, there are simple methods and displays which relate closely to more or less conventional approaches and make significant use of attributes such as velocity, frequency, and phase. The insights which can be developed are of particular value in stratigraphic studies, especially on land where amplitudes embody so much greater uncertainty.

Key results which can be readily established include an appreciation that large scale velocity changes are often directly indicated by stacking velocity slope changes. High frequency reflections can often delineate major changes in lithological sequence and point out with clarity "specular" reflecting boundaries such as lava sills and fluid contacts. Finally, study of phase properties makes clear that synthetic seismogram rather than the inversion section is the proper place to note phase differences and to make adjustments.

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