Recognition of Acceleration and Additional Oil Recovery Opportunities Using Numerical Reservoir Simulation Techniques
Authors: Dietrich James K. 
Published: December 2007

This paper was prepared for the 48th Annual Fall Meeting of the Society of Petroleum Engineers of AIME, to be held in Las Vegas, Nev., Sept. 30-Oct. 3, 1973. Permission to copy is restricted to an abstract of not more than 300 words. Illustrations may not be copied. The abstract should contain conspicuous acknowledgment of where and by whom the paper is presented. Publication elsewhere after publication in the JOURNAL OF PETROLEUM TECHNOLOGY or the SOCIETY OF PETROLEUM ENGINEERS JOURNAL is usually granted upon request to the Editor of the appropriate journal provided agreement to give proper credit is made.
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Abstract
A mathematical model of the reservoirs which are currently being waterflooded in the Middle Ground Shoal field of Alaska has been constructed and calibrated to match the six-year water production and pressure history in this field. The reservoir description and performance data are stored on magnetic tape and performance data are stored on magnetic tape and updated periodically. Thus the model represents a retrievable reservoir engineering tool for prediction of field performance under a variety prediction of field performance under a variety of short and long-term operating strategies. It has been recognized through application of this tool that acceleration of income and additional oil recovery will result from expansion of the current artificial lift capacity, control of produced water and additional drilling. produced water and additional drilling

Introduction
The evolution of solution techniques involved in reservoir performance predictions has prompted an accompanying change in the requirements for reservoir description. No longer are the assumptions of uniform rock properties and fluid saturations used in the properties and fluid saturations used in the classic Stiles and Dykstra-Parsons models sufficient for the calculation procedures. For the first time, geologists and engineers are being asked to quantify variables which have heretofore received only qualitative assessments.
The degree of success which a simulation achieves in terms of meeting its specified objectives may directly reflect the amount of physical detail preserved in the mathematical physical detail preserved in the mathematical model. At the stage in the life of a reservoir when infill drilling or supplemental recovery projects are planned or in operation, simulation projects are planned or in operation, simulation to predict future performance requires a careful description of the variables which determine the magnitude and distribution of the displaceable oil and the capacity of the formation to transmit and store fluids. The accuracy necessary in the description process becomes exceedingly important when attempts are made to model heterogeneous, multilayer reservoirs.
This paper presents the techniques which were used to describe the complex reservoirs of the Middle Ground Shoal field, which lies beneath the waters of the Cook Inlet approximately 60 miles southwest of Anchorage, Alaska. This field is one of five known petroleum accumulations in an area of the Cook petroleum accumulations in an area of the Cook Inlet commonly referred to as Oil Alley, and it ranks number three in terms of reserves and productive capacity (Figure 1). productive capacity (Figure 1).