Impact of high-resolution seismic from reservoir modeling Minagish Oolite reservoir, Minagish Field, Kuwait. 9th Middle East Geosciences Conference, GEO 2010.

Abstract

The Minagish Field has several reservoirs with oil accumulated primarily in the Lower Cretaceous middle member of the Minagish Oolite rocks (MMO). This giant carbonate hydrocarbon accumulation was discovered in 1959 and accounts for over 90% of oil production in the field. As the reservoir pressure started to decline, there was a need for water injection on the flanks of the structure to support the reservoir pressure and to increase the oil production. The sequence-stratigraphic analysis based on well logs, cores and the old 3-D seismic subdivided the reservoir into 13 geological layers with multiple phases of ooid shoal development. The Minagish Oolite reservoir has a 50 to 120 feet thick tar mat underlying the oil column. It is present in many, but not all, flank wells. It occurs at differing depths, between 9,700 ft and 9,935 ft TVDSS, and is deeper to the south of the field. The water has been injected in the layers above and below the tar mat in order to support the reservoir pressure on the crest. The well surveillance data interpretation of the injector Well MN “A” shows that layers below tar mat have very low injectivity compared with the layers above. The nearby producing Well MN “B” shows a water breakthrough in the upper layers whereas the lower layers are not affected by water. The lower oolite sediments possibly have a moderately progradational clinoforms stacking pattern which are weakly imaged by the old conventional 3-D seismic data. There is some uncertainty in the definition of flooding events between wells. In 2006, a high-resolution 3-D seismic survey was acquired to improve reservoir characterization. Progradational dipping clinoforms geometries are detected to the east of Minagish structure which led us to better definition of the reservoir architecture at this particular area in the field. This has a direct impact on Minagish Oolite reservoir modeling.