An Integrated Reserves Administration And Evaluation Tool
Authors: Joziasse Peter , Van Doorne Glenn 
Published: March 2010

Abstract
Canterra's Reserves Administration and Evaluation System (CRAES) was developed in response to two needs: maintain a complete inventory of corporate hydrocarbon and sulphur reserves; and generate realistic cash flows and values/or those reserves. To be an effective management tool, the system also had to fulfill following requirements: provide accurate and timely technical and financial management information; meet regulatory reporting requirements; make use of and be consistent with other corporate data such as land information, production history data, and budget and planning projections; and be cost-effective and time efficient.
Basic reservoir parameters, well data, P & NO interests, and the most current production history data are maintained within CRAES to determine remaining recoverable hydrocarbons in every lease in which the company has an interest. An elaborate audit system permits detailed reporting of reserves and reserve changes resulting from discoveries, acquisitions, divestitures and technical re-evaluations.
An economic evaluation of all remaining hydrocarbon and sulphur volumes is conducted regularly, using capital, operating cost and production projections from the production departments and price and escalation forecasts from the planning department. The resulting cash flaw forecasts and reserve values are used by the finance and production departments/or future planning.
The CRAES database is integrated with other corporate databases and provides comprehensive management and reporting of corporate reserves.

Introduction
Maintaining an accurate and current record of inventory is an essential characteristic of good business practice. The petroleum industry is no exception to this rule, although the "inventory" is not as well defined as in most businesses. Petroleum "inventory" consists of oil, natural gas, and natural gas by-product reserves. These reserves may be located in underground reservoirs scattered over a large geographical area, in tanks and vessels at surface, in pipelines, in storage caverns, or even sitting exposed on the ground, such as sulphur inventory. However, most reserves are located in the ground.
The measurement of reserves is an inexact science at best, and is subject to ongoing updating as additional technical information becomes available. Reserves are acquired, produced, and sold in a variety of ways, Therefore, maintaining a current reserves record is a major task, especially as the size of a company's operations increases.
Reserves information is required by a company's operating personnel to permit production planning, to determine capital spending programs for exploitation and development, to assess surface facility requirements, and to monitor production performance. It is required by financial personnel for future revenue planning, for depletion calculations, and to back up loan arrangements. It is required by external agencies such as securities commissions and financial institutions, and it is required by current and potential investors in the company.
This paper presents the current system Canterra is using to administer its reserves information, and describes its origin, development, and application.
The maintenance of reserves information has been an evolutionary process in most companies. As specific reserve related information is required, the reserve system, or process, is upgraded to provide that information.