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Hardage et al. (1994) conducted a study at Stratton Field with the purpose of detecting thin‐bed compartmented reservoirs in a fluvially deposited system (Oligocene Frio Formation), and rightly concluded that, in order to determine which seismically imaged stratigraphic changes are compartment boundaries, it is necessary to incorporate geologic and reservoir engineering data (particularly reservoir pressure data) into seismic interpretation. Their interpretation philosophy consisted of defining depositional stratal surfaces (I would rather say paleodepositional surfaces), and in analyzing seismic reflection amplitude behavior on such surfaces.

Although seismic stratigraphy has come of age, many interpreters still pay little, if any, attention to seismostratigraphic information. Alistair Brown justly pointed out the importance of seismostratigraphic interpretation (TLE, November 1992), but he insisted on the surface‐oriented approach. The surface‐oriented approach is useful for analysis of stratigraphic details, but extraction of all stratigraphic information from seismic data is not possible if it is applied alone.

Hinds et al.’s paper is an interesting case history describing the acquisition and interpretive processing of VSP data and presenting an integrated interpretation of well log, surface seismic, and vertical seismic profile data. However, a question of principle arises. What is an integrated interpretation?

In his interesting paper “Seismic interpretation today and tomorrow” (TLE, November 1992), Alistair Brown rightly emphasized the importance of 3-D seismic data. It goes without saying that subsurface imaging based on 3-D seismic data is much better than that based on 2-D. But it should be pointed out that the optimum subsurface imaging can be obtained only by 3-D depth‐migrated seismic data.

Two principal elements of the hydrocarbon generation model proposed by Ejedawe and Coker (1984) are as follows. (1) Organic-matter maturation occurs in two phases. The first phase corresponds to basinal subsidence with essentially constant burial rate and geothermal gradient; therefore, the oil-generative window (OGW) is fixed in space. The second phase is the postsubsidence phase when "all materials remain at constant temperatures appropriate to their depths" (p. 1028), and "the OGW moves vertically upward through the static sedimentary fill, and maturation is due to time effects" (p. 1024). (2) Hydrocarbon generation begins "with the lighter hydrocarbons (or even thermogenic gas) at the initial OGW at depth, followed by progressively heavier hydrocarbons as the OGW moves vertically upward" (p. 1024).