What are the objectives of a seismic interpretation? Are the objectives the same today as they were 40 years ago? Certainly today’s 3-D seismic data and computer workstations have added tremendous interpretative abilities that weren’t present 40 years ago—or even dreamed of! However, these are only tools for accomplishing the objectives. Unlike the frequency content of seismic data, the objectives of a seismic interpretation aren’t time varying.
The objectives listed in Fig. 1.A.1 are paraphrased from Jakosky’s book published in 1960. The first objective, “Recognizing a hydrocarbon anomaly,” is still paramount in today’s seismic interpretation. However, our recognition criteria have been greatly enhanced with modern true amplitude acquisition and processing. Seismic amplitude is now one of the major criteria for recognizing potential hydrocarbon reserves.
The second objective, “Validating an anomaly,” might be expanded to include stratigraphic framework through the interpretation of the seismic waveform patterns. However, let’s incorporate stratigraphic validation in the structural interpretation of the geologic framework. In short, find an anomaly, map the structure, and make sure the seismic reflection amplitude is consistent with the structural interpretation.
While the recognition and validation of a potential seismic anomaly might be the interpreter’s objectives, management also has its own. Besides the upside economic value of the prospect, some aspect of risk must be assigned to the prospect, if for no other reason than for trying to decide which prospect to drill first. The management requirement can be stated several ways. One is: “Identify where art dominates and science deviates in the structural and amplitude interpretations.”