Adiministracion integral de yacimientos.

...

The Microcosmic Approach

If for any reason logs and build-up data are unavailable but cores exist. the best approach to determining parameters of interest (at least on the basis of present knowledge) is the following. Find the core with median permeability and use the porosity. irreducible water saturation and relativepermeability characteristics of this core to represent those of the whole reservoir. In strong contrast to the preferred holistic philosophy, this method may be regarded as the "microcosmic" approach to the determination of reservoir parameters. Its rationale lies in the probablistic reconciliation of core data with gross reservoir measurements that has been carried out at Gulf by Warren, et al. These studies have shown that the most probable core properties, based on agreement

with gross reservoir properties measured in situ, may be derived from the core having median permeability.

Conclusion and Advice

In the foregoing a lot of ground has been covered. Some of that ground has been covered rather sketchily because of the exigencies of space. The subjects I have chosen to discuss happen to be ones of interest to me. It is an idiosyncratic, not a catholic, choice. Were I to dwell on all the difficulties and problems that beset the reservoir mechanic, I could write almost indefinitely. It is customary in our present parlous and rather earnest civilization for writers of a discussion on this type to end with some sort of message. I find this difficult to do because I am not didactically inclined. Nevertheless, I will try to summarize what I have written in the following terms. Petroleum engineers and reservoir mechanics are daily engaged in a task of utmost importance and singular complexity. They are, quite literally, dealing with nature and its forces. Nature is a tough cookie. She is not going to be overcome by "gobbledegook" and technical double-talk. Chances are even slimmer if an engineer is pompous or otherwise takes himself too seriously. Nature can be persuaded to cooperate only if she j, approached with patience, with humor and with some pretense to intellectual and scientific honesty. In the field of petroleum recovery, she is most readily seduced if she is approached with a sympathy and understanding developed by intelligent, basic laboratory research. That is my Message.