An Integrated Summary of Formation Evaluation Criteria

This paper summarizes and integrates the various methods used for formation evaluation. Specific objectives are listed and the limitations of instruments and techniques are given. All hydrocarbon-bearing zones, subject to formation evaluation, are classified under five group headings. The classification gives a physical description and examples of typical geological zones. The total problem of formation evaluation, as applied to each of the five classified formations, is given. Wells are classified in accordance with their objective, that is, wildcat, field extension, or development. A basic evaluation program is recommended for each formation and well type. Introduction The principal objective of this symposium has been to consolidate and integrate all methods of formation evaluation. Detailed coverage has been given concerning the theory, instrumentation, and techniques of electric logging, radioactive logging, mud analysis logging, core analysis, and drill-stem testing. Specific studies of all types of major oil and gas producing formations have been presented. The purpose of this paper is to summarize and integrate the more important aspects of the previous papers, principally those concerned with the specific field studies, and to present a constructive survey of the formation evaluation problem.