Anguille Marine, a Deep-Sea Fan Reservoir Offshore Gabon: From Stochastic Modelling Toward History Matching (1992)

Anguille Marine, a Deep-Sea Fan Reservoir Offshore Gabon: From Stochastic Modelling Toward History Matching C.B. Giudicelli; C.B. Giudicelli Elf Aquitaine Search for other works by this author on: This Site Google Scholar F.G. Alabert; F.G. Alabert Elf Aquitaine Search for other works by this author on: This Site Google Scholar G.J. Massonnat; G.J. Massonnat Elf Aquitaine Search for other works by this author on: This Site Google Scholar Bernard Corre Bernard Corre Elf Italiana Search for other works by this author on: This Site Google Scholar Paper presented at the SPE Annual Technical Conference and Exhibition, Washington, D.C., October 1992. Paper Number: SPE-24894-MS https://doi.org/10.2118/24894-MS Published: October 04 1992 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Giudicelli, C.B., Alabert, F.G., Massonnat, G.J., and Bernard Corre. "Anguille Marine, a Deep-Sea Fan Reservoir Offshore Gabon: From Stochastic Modelling Toward History Matching." Paper presented at the SPE Annual Technical Conference and Exhibition, Washington, D.C., October 1992. doi: https://doi.org/10.2118/24894-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE Annual Technical Conference and Exhibition Search Advanced Search AbstractThe Anguille Marine field, located offshore Gabon, lies in a complex heterogeneous turbiditic formation. A geological/ geostatistical approach was applied to create 3D images of the reservoir. The flow simulation of the 25 years of production history was performed after a severe upscaling from more than two millions gridblocks to 11,000 ones. The difficulties in matching the observed behaviour of the field raised several questions regarding the upscaling process, the geological model and the relationship between the two. The use of partial models helped greatly in tracking the origin of the discrepancies. The choice of the aggregation rate proved to he too important in this case of heterogeneity. It should be optimized when dealing with strongly heterogeneous stochastic models.IntroductionThe Anguille Marine field is located on the west coast of Africa, in the Gulf of Guinea, offshore Gabon (see Figure 1). It was discovered in January 1962 on a lease operated by Elf Gabon. Five delineation wells were drilled by 1963 ; the field was put on stream in 1966. Reservoir management policy was initially natural depletion. After 2 to 3 years of production, several wells experienced a severe GOR increase due to a lack of pressure maintenance. To remedy this problem, water injection was chosen and several injector wells were drilled. The efficiency of the water injection scheme did not prove to be as good as expected : reservoir pressure was effectively stabilised but poor areal sweep was suspected as water broke through very sharply at several producers.Moreover, infill drilling revealed itself to be a risky business with some dry holes or disappointing reservoir quality. Recently, a complete geological analysis was performed by a multi-disciplinary team involving geologists, log analysts and reservoir engineers. The methodology which was used is fully described in reference 1. The reservoir of Anguille was then described as an extremely complex reservoir in a turbiditic environment, where heterogeneity prevails through good permeability sands in lobes and channels embedded in poor reservoir laminated facies.The use of stochastic techniques was found to be of great help in the modelling of such a geological environment. The complete analysis is developed in a companion paper (see reference 2) : It provided finally 3D images of the reservoir where only one of the eight elementary facies (see Table 2) is assigned to each gridblock. The subsequent step is the translation of the fine geological model, generated by the stochastic process, into a reduced model aimed at studying flow properties with a classic black-oil simulator. Final goals of such a procedure are the understanding of current recovery mechanisms for improved future reservoir management. The methodology planned for performing this task has been partially presented in reference 3.The present paper deals with the problems encountered during the simulation phase and the upscaling from the fine-grid stochastic model to the coarse-grid simulation model.The first section concentrates on the full-field model which reveals some difficulties in representing the actual field behaviour. The second section presents two types of partial models which have been used to locate and to understand the above problems, as well as to validate the geological model.P. 371^ Keywords: upstream oil & gas, reservoir offshore gabon, spe 24894, anguille marine, full field model, permeability, heterogeneity, facies, fluid dynamics, thin model Subjects: Reservoir Fluid Dynamics, Reservoir Simulation, Flow in porous media This content is only available via PDF. 1992. Society of Petroleum Engineers You can access this article if you purchase or spend a download.