This paper presents the results of Reservoir Management in the Centenario Field (Neuquen Province, Argentina), operated by Pauspetrol in December, 1977. The field was produced by primary recovery from 1967 to 1980, when conventional water injection was initiated in two partially-depleted fault blocks. Since performance at the outset differed from that predicted, a detailed Reservoir Characterization study was carried out and an operating plan implemented that included strategy of continuous monitoring of performance and adjustment of operating parameters that continues to give excellent results.Results, observations and conclusions. Continuous updating of the reservoir model has made it possible to successfully drill 58 new wells and perform 168 workovers and modifications to the water injection system, which have resulted in production of an additional 2.5 million m~3 of oil from June 1983 to date. This clearly illustrates the necessity of permanent monitoring and constant modification of the operating plan of water-flooding in heterogeneous reservoirs. The success or failure of this type of project is critically dependent upon understanding the reservoir rock and fluid system, as well as constant monitoring of performance, which in this case has led to recovery of more than 50% of original oil in place. Due to the wide areal dispersion of reservoir parameters, the traditional practice of pilot flooding to predict full-scale performance is not applicable to highly heterogeneous fields. Pilot performance depends upon the locations of the production and injection wells and cannot be extrapolated. For the sake of simplicity, and in order to illustrate the methods used to determine petrophysical properties, areal distribution of pore space and reservoir barriers that affect oil recovery, this paper will be limited to the southeastern sector of the field, the area that posed the most problems.Applications and technical contributions. The results show that multidisplinary reservoir management, together with application of the principles of continuous improvement, can be applied to the exploitation of oil fields with excellent results. The technical contribution is to introduce the concept that dynamic injection schemes in highly heterogeneous reservoirs can increase ultimate recovery in waterflooding projects.
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