By KEN MALLON

Glossary Is a Useful 'Resource'

Editor's note: Mallon is AAPG's liaison to the SPE Oil & Gas Reserves Committee.

Intersociety efforts among three geoscience groups to find a common language for the petroleum resource classification and reserve evaluations guidelines have taken another step toward unity.

The result is a new "Glossary of Terms" document that seeks to end misunderstandings between the various disciplines.

The initiative involves AAPG, the Society of Petroleum Engineer's Oil and Gas Reserves Committee and the World Petroleum Council (WPC), which previously resulted in the sponsoring and publication of the "Petroleum Resources Classification and Definitions," and the "Guidelines for the Evaluation of Petroleum Reserves and Resources" (see August 2002 EXPLORER).

AAPG involvement has come through its Committee on Resource Evaluation.

Since publication in 2001, the classification system and guidelines have had a very favorable response from operating and producing companies, consultancies and government agencies worldwide. Many companies and agencies are following the classification system as published, or are using it as the basis for their own internal classification systems.

The documents have been publicized in several AAPG, SPE and WPC publications, and have been the subject of numerous technical papers and presentations.

Razing Towers of Babel

The earliest and most common critical comments of the works involved the variety of definitions throughout the world for various terms used in all the new resources documents. It was evident that in the operating world there are many terms used in the oil and gas industry that have different meanings for different people. Countries and governmental agencies quite often have their own internal interpretation of specific terms.

Suppose you asked a roomful of international geologists and engineers to define a few terms -- for example, "analogous reservoir," "commercial" and "lowest known oil." Most likely, you'd get many different responses.

Worldwide feedback, then, spurred the three societies to assemble -- and in part write -- a glossary of terms used in the various reserves and resources documents published by the SPE.

This lexicon, intended to clarify the meaning of those terms used in the reserves and resources documents, was finished earlier this year.

The Glossary has been published by SPE, and a direct link to it can be found via a gateway on the AAPG Web site.

Also available on the Web site for viewing and printing are the reserves and resources definitions and the Resource Classification System. There also is a link to purchasing instructions for the soft cover, 100-plus-page "Guidelines for the Evaluation of Petroleum Reserves and Resources."

The Glossary illustrates the power of cooperation among the AAPG, SPE and WPC. The organizations and members involved in this important intersociety work hope that these documents foster a better understanding of reserves and resources worldwide.