Kudos for putting this article up. It’s not often the world gets to hear about the complexities of reservoir engineering, which is both an art and a science, bounded by imperfect information and imperfect correlations. Sometimes the reservoir engineering decisions work out; sometimes not.

I worked for a while as a pressure transient analyst. The head guru of this company privately said to us that the software we are using to determine gas deliverabilities should have a caveat of +/- 100% for any well. But if we average 100 wells for composite deliverability, the software provides an accurate estimate.

I’m not sure who the audience for this article. If it is to be a primer for a reasonably well educated lay person, it is too technical for them to understand. If the audience is the scientific community or non-petroleum engineers, I think they too need a better primer. Usually such primers spend time on concepts as porosity and permeability. The Klinkenberg effect is irrelevant in a primer.

As a former petroleum engineer, the article falls short in accuracy. The topics are not brought together very well. And I would say that it should be at least five times the length with other “primer” topics, including a better explanation of reservoir simulation.