The estimation of reserves of oil, gas and related substances has been a hot topic since the very beginning of the oil industry. Over the ensuing years, the concept of reserves has meant different things to different people within this industry. Each evaluator, oil and gas company, financial agency, securities commission and government department uses its own version of the definitions.
This poster presentation and the accompanying monograph compiled by the Petroleum Society of the Canadian Institute of Mining, Metallurgy, and Petroleum (CIM) represents our effort to find definitions and guidelines for the classification of reserves that will be acceptable to ali of these users.
The topics covered have naturally divided themselves into four parts. Part One presents the definitions and guidelines for the classification of oil and gas reserves. These have been prepared by the Standing Committee on Reserves Definitions of the Petroleum Society of CIM.
Part Two discusses the volumetric and material balance methods for estimating volumes of oil and gas in piace, various sources of data, and the interpretation of data. Part Two also deals with probabilistic methods of estimating volumes of oil and gas contained in reservoirs in addition to the more common deterministic methods.
Part Three considers the estimation of recovery factors for oil and gas reservoirs, with particular emphasis on volumes recoverable by enhanced recovery methods. Secondary and tertiary recovery methods, as well as primary methods and the use of horizontal wells, are discussed. Part Three also addresses decline curve analysis and reservoir modelling by numerical simulation.
Part Four covers the other factors that must be considered in estimating reserves. These include the assessment of uncertainty, cash flow analysis, the role of markets, and potential regulatory impacts that should be recognized.
PART 1-DEFINITIONS AND GUIDELINES FOR CLASSIFICATION OF OIL AND GAS RESERVES The definitions of key terms and reserves classification are given in Part 1 of the CIM monograph.
They are similar to those currently in use, particularly in North America. The definitions have been reviewed by users in the oil and gas industry, and representatives from regulatory agencies, government departments, industry associations, and technical and professional organizations.
Definitions of related terms prepared in conjunction with the reserves definitions are included in the Glossary at the end of the monograph.
Guidelines that illustrate the application of the definitions and the classification system are also presented in Part One. These are intended to complement the detailed guidelines on reserve estimation methods and procedures that are presented in the mon o g r a p h.
Part One of the monograph has been prepared by the Standing Committee on Res