Incremental Benefits of a Team Approach to Reservoir Management
Authors: Thompson Robert S. , Van Kirk Craig W. , Benson Robert D. , Davis Tom L. , Graves Ramona M. , Slatt Roger M. 
Published: December 2007

Abstract
Teamwork is the norm for the petroleum industry where teams of geologists, geophysicists, and petroleum engineers work together to improve profits through a better understanding of reservoir size, compartmentalization, and orientation as well as reservoir flow characteristics. An integrated study of the Terry Sandstone production from the Hambert-Aristocrat Field, Weld County, Colorado was used to document the process of integration.
The process of integration has proven to be iterative. This paper gives specific examples of how a multidisciplinary approach was used to improve the reservoir description and to narrow the uncertainty in the reserves estimates in the study area. The incremental benefit of narrowing the uncertainty in reserve estimates is estimated to have a NPV discounted at 10% of $20 million for the area studied. This work, done with the support of the Department of Energy, is directed to the needs of the independent oil producer.

Introduction
The Hambert-Aristocrat Field in the Denver Julesburg Basin in Colorado was selected to test methods of integration. The Denver Julesburg Basin, Fig. 1, has been one of the most active in the country. The Hambert-Aristocrat Field, discovered in 1972, produces oil and gas from the Cretaceous Terry Sandstone along the east side of the Denver Basin. The Terry Sandstone in the study area produces from a depth of approximately 4500 feet, and there are approximately 101 Terry completions.
Teamwork and integrated reservoir management is the current method of problem solving in the petroleum industry. A specific project goal is to demonstrate how a multidisciplinary approach can be used to detect reservoir compartmentalization and to improve the reservoir description and reserves estimates. This paper presents a discussion of the concept of multiple working hypotheses, a general strategy for integration, a final interpretation for the study area, examples of integration, and the economic benefits of reducing the uncertainty in reserves estimates.

Multiple Perspectives
The challenge for the independent operators is to know when to integrate and at what level the integration should take place to make the most out of available data. Cycle time for the iterations, another consideration if profits are to be maximized as a result of the integration, are not addressed in this research.
The approach espoused by T.C. Chamberlain in his classic paper "The Method of Multiple Working Hypotheses" is the challenge for independent oil and gas operators. This classic paper is based on a presentation made by T.C. Chamberlain in the late 1800's. This paper is significant since it challenges the investigator to consider multiple perspectives rather than using the "Ruling Theory" where we interpret before the facts are known or we hinge our interpretation on a single working hypothesis and force the facts to fit the hypothesis. In practice, application of the concept of multiple perspectives is not easy. When we read the literature (as we should) it is easy to fall into the trap of forcing the facts to fit the current interpretation.