Application of Optimization Methods to Oilfield Problems: Proved, Probable, Possible
Authors: Dougherty E.L. 
Published: December 2007

This paper was prepared for presentation at the 47th Annual Fall Meeting of the Society of Petroleum Engineers held in San Antonio, Tex., Oct. 8–11, 1972. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by who the paper is presented. Publication elsewhere after publication in the JOURNAL paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made. provided agreement to give proper credit is made. Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
In recent years a large number of papers have been published reporting applications of optimization methods to oil field problems. Results of these studies are becoming of increasing significance to field engineers as well as research specialists. Topics covered include drilling, oil field development and production planning, well maintenance and stimulation planning, well maintenance and stimulation efforts, bidding strategies, automatic history matching of reservoir simulation models, use of statistical and probability methods and improved ways to deal with risk, exploration project selection and planning, and planning, design and operation of natural gas production, storage and delivery systems. Important developments in each of these fields are surveyed, benefits estimated and direction of possible future work suggested. Results of an industry survey are reviewed.
It is concluded that scope and importance of efforts has expanded as a result of increasing computing power and knowhow and more forward-looking management views. A key factor in achieving significant benefits, which have varied from very large to nil, has been picking the right problem and concentrating on it. Development is likely to continue apace with increasing emphasis on obtaining better data and using broader and more flexible solution systems.

Introduction
Although there are undoubtedly many learned definitions of what a review paper should contain, I have not read any that I remember. Thus, guidelines followed in writing this paper may be official in only a very limited sphere. When I read a review paper, I consider it well done if it paints a clear and intelligible picture of the subject—showing the high points picture of the subject—showing the high points and the low points and some details of the terrain in between. What methods are used, how do they work, how good are they and what are limitations, what kinds of problems can they be used on, what benefits have been realized, what can we expect in the future, what papers and books should be referred to for more information—to answer as many of these questions as possible about some logical set of categories possible about some logical set of categories covering the subjects was the guideline followed.
As appears to be standard procedure in preparing a review paper, a large number of preparing a review paper, a large number of papers and books were scanned. Those deemed papers and books were scanned. Those deemed pertinent were read and included herein. In pertinent were read and included herein. In addition, a questionnaire was prepared and mailed to about 50 individuals. 20 replies were received. These were most helpful; a summary of the responses is given.