A Quick Method of Identifying and History Matching A Gravity Dominated Reservoir with Localized Super-Permeabilities

Abstract

Abstract: This paper discusses a quick method of identifying and history matching gravity dominated reservoir area with localized Super-permeabilities (Super-K). The area of interest is part of a large elongated carbonate antic line Middle-East oil reservoir. Wells in the area of reservoir of interest are prolific producers with a high degree of Super-K occurrences. Layers with Super-K usually contribute more than half of the flow from few feet interval. Figure-l is a flowmeter which indicates a flow contribution of more than 50% from a dolomitic Super-K layer. The lack of geological data and wide well spacing offers little help in identifying the areal extents of these Super- K layers. Therefore, correctly history matching the reservoir may be difficult due to the non-uniqueness nature of reservoir modeling that the match may be achieved with a wide variety of reservoir descriptions and permeability arrays. However, if the reservoir fluid mechanic could be identified, then the history match may be facilitated. The paper will discuss:a quick procedure of identifying whether the Super-K are localized or are a really widespread by using the simulation model in conjunction with flowmeters and production data.A quick procedure for pressure and saturation match. These procedures are practical and help identify the reservoir fluid mechanics at the beginning phase of history matching. In the case of the reservoir of interest, the model helps prove that most of the reservoir is gravity dominated even with a high degree of Super-K occurrences. The paper will outline how the well test permeability thickness data and the flowmeters are employed in constructing the model. It will discuss a quick, systematic procedure of pressure and saturation match. The overall match was achieved in a short time of a model with approximately 100 wells. The discussion will highlight the fact the knowledge of reservoir fluid mechanic and its behaviour is important before any attempt of history match is made. P. 753