Introducing a strategy in recognition and simultaneous modelling of fractures with FMI logs and seismic data through reservoir zonation in a field from south of Iran

Document Type : Original Article

Authors

1 دانش آموخته کارشناسی ارشد، مهندسی اکتشاف نفت، دانشکده مهندسی معدن، نفت و ژئوفیزیک، دانشگاه صنعتی شاهرود

2 Sahrood University of Technology

3 Faculty of earth Sciences, Shahrood University of Technology

4 Iranian Offshore Oil Company

Abstract

Fracture identification is an important step in reservoir modelling and production management. Fractures are among the most important parameters that influence fractured carbonate reservoirs. interpretation of high resolution data such as fullbore formation microimage (FMI) log provide valuable information about distribution and properties of fracturs. The FMI log will also separate closed and open fractures. Obviously open fracture provides ability of fluid movement- permeability- in the reservoir and thus define production ability of the reservoir. However, availability of FMI logs through the whole reservoir is some time a problem while its effective radius is small, too. Thus, integrating fracture modelling with seismic data and FMI log will provide a complete fracture model of the whole reservoir. In this study, we have introduced an integrated strategy for fracture modeling using seismic and FMI data. The strategy was applied on a fractured carbonate reservoir from the Persian Gulf. In the presented strategy, the facture will be identified initially by the FMI log, and then the fracture intensity and cumulative intensity logs were derived. Subsequently by defining zonation area based on fracture intensity cumulative log gradient, primary zonation of the formation reservoir was performed. In this step, fracture model from seismic data was integrated by the upscaled fractures model from well data. Hence, four fracture zone identified in the upper formation reservoir and two in the lower one. Based on this model, one zone from each formation were proposed for further study.

Keywords


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