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A few days after I posted my reply on this topic it occured to me that perhaps the answer depended on what kinds of questions the seismic interpreter is being asked.

For the brief time I worked in the field structure was the essential question - was there a bump there or not? But then velocity inversions came in and the questions began to change to is there or is there not gas in these rocks, and later while I was looking for a job either as a geologist or as a geophysicist one of my interviews was with a fellow who was trying to follow channels using 2D (1982).

If structure or some physical attribute of the section (velocity changes, phase changes, etc) is the question then I would go with the geophysicst with a strong background in data acquisition and processing. And especially if the question is does this change in signal attribute represent something real in the rocks or is it an artifact of the processing.

But if the question is one of stratigraphy or stratitgrahic variation over an area and/or depth range then I think the geologist might have the upper hand, particularly if they have had a lot of outcrop experience in sedimentary rocks deposited in the type of environment being postulated.

Those are just my thoughts. But having been out of the field so long I am curious about what kinds of questions the seismic interpreters are being asked now and if my thoughts make any sence to those of you still in the business.

Darryl

Darryl: your first response was very thoughtful as well but I really agree with your second response. In fact, its another emerging trend I've noticed that it depends on what questions are being asked of the interpreter.
Also, i talked to one very experienced and well known interpreter and he had a response which i think you might all enjoy. He said that when everything was conventional production, the main reason you would have a geophysicist instead of a geologist doing interpretation is because data quality was often poor and processing was not as well developed as it is today so a geophysicist who understood the constraints of the data were used. Otherwise a geologist would be preferred. Then as data quality and processing improved it reduced the need to have a geophysicist when you can have a geologist who understands the geologic features interpret the exquisitely fine detail seismic. However, fortunately for geophysicists, as data quality improved it just so happened that the oil industry went through changes and the questions being asked of seismic interpreters changed as well. Now that unconventional reservoirs are being produced and big safety/environmenntal concerns need to be addressed(we're all aware of the gulf of mexico disaster) the questions being asked of interpreters brings back the need for geophysicists to take on seismic interpretation roles. In fact, interpreters, he says, are needing to have a stronger math/physics background than ever before to answer questions regarding the mechanical properties of rocks (brittlenes, stress fields, young's modulus, fracability), caprock integrity (safety/environmental) and the time evolution of reservoirs (ie. Using 4D seismic to monitor changes during production) can be answered. Anyways, this has been a good and insightful discussion.

I know several geophysicists and geologists. Truth to be told, each can be better than the other. It just depends how much experience they have. All in all, they all try to achieve the same - the means are just different but it all boils down to personal skill.

At least that's what I am seeing after a few years in the industry.