Performance of Oil Wells in Bottom Water Drive Reservoirs
Authors: Miller R.T. , Rogers W.L. 
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.
Discussion of this paper is invited. Three copies of any discussion should be sent to the Society of Petroleum Engineers office. Such discussion may be presented at the above meeting and, with the paper, may be considered for publication in one of the two SPE magazines.

Abstract
The purpose of this paper is to provide a clear and logical understanding of the effects of underlying water on short- and long-term well performance. Two and three phase, compressible performance. Two and three phase, compressible two-dimensional numerical simulators, which are implicit in saturation, have been used to simulate the performance of individual wells with underlying water.
The first part of the study was devoted to an investigation of short-term performance. The simulator was used to model a high rate production test to determine that there was enough production test to determine that there was enough time after the well was shut-in to log the well to establish the position of a water cone, and that the production of water would not permanently impair the performance of the well. The simulator was also used to determine the most significant performance parameters which influence water coning. performance parameters which influence water coning. The long-term performance of a well completed in a representative Offshore Louisiana, light oil reservoir was investigated to determine the most desirable range of production rates, well spacing, and completion interval for different values of significant reservoir parameters. It was found that for the conditions parameters. It was found that for the conditions investigated higher production rates, even with the attendant higher water production, gave increased ultimate recovery as well as profit.
The long-term performance of a well completed in an onshore reservoir, having an unfavorable mobility ratio, was also studied. Again the higher production rates appeared to be the most desirable.

Introduction
The majority of the oil production in the Texas and Louisiana Gulf Coast both on and offshore comes from sandstones, and the overwhelming fraction of offshore production comes from reservoirs having at least a partial water drive. One of the major reservoir engineering problems in these areas has been associated with the ability to accurately predict the performance of wells producing predict the performance of wells producing above an oil-water contact.
Oil reservoirs found in this area may be divided into three main classes, which, of course grade from one type to another:The classic bottom water reservoirs in which nearly the entire reservoir is underlain by the oil-water contact.The relatively thick low dip sands wherethere is a strong edgewater drive component, but individual wells essentially behave asthough they are producing in a bottom waterdrive reservoir.