Abstract
The paper proposes a systemic multi-criteria methodology for evaluating the efficiency of oil reservoir development under incomplete, heterogeneous and fuzzy input information. The relevance of the study is determined by the fact that, at the late stages of oilfield development, managerial decisions are made under the simultaneous influence of geological, technological, operational, economic and informational factors. A purely deterministic description of such objects does not always allow engineers to incorporate poorly structured expert knowledge, uncertainty of production data and conflicting efficiency criteria. The aim of the paper is to develop a methodological framework integrating systems analysis, fuzzy set theory, expert assessment, multi-criteria optimization and elements of well stock forecasting. The paper presents a structural model of an oil reservoir as a complex dynamic system, a set of efficiency criteria, membership functions for quantitative and qualitative indicators, an integral efficiency index and an algorithm for ranking technological alternatives. The practical significance of the methodology lies in its application to operating mode selection, well stock regulation, evaluation of enhanced oil recovery measures and development of a decision support system for oil production companies.