Massive mud losses, well logging, seismic data together with observed conformance issues and significant variation in well performance suggest a well developed fracture system in a regional Shuaiba reservoir. Proper characterization of such fractures plays a critical role in modeling reservoir fluid flow and production. Fracture corridors are the dominant fluid flow paths in Shuaiba reservoirs and are the focus of this study. Their spatial distribution and conductivity are characterized by integrated analysis based on drilling, logging, core, seismic, and well performance. Geological analysis, including tectonic/structure history, strain/stress variation, and rock mechanical stratigraphy are performed to better understand the fracture system. Overall well performance is clearly related to fracture distribution throughout regional fields. During early stages of production, before water flooding, conductive fracture corridors connected the underlying aquifer to producers and occasionally resulted in premature water breakthrough in high strain areas. Following the implementation of water injection, these fracture corridors also connect some injectors and producers. As a result, continued development requires recognizing and mapping these fracture corridors. This is done by acquiring saturation data in recent horizontal wells. Together with borehole image data, the width and configuration of fracture corridors can be characterized. A practical approach is taken in 3D fracture modeling. Fracture corridors are interpreted in 3D by integrating all static and dynamic data available. Their conductivity is classified into high, mid and low using dynamic data and mud losses. Fracture distribution and flow properties are related to or constrained by geologically more predictable attributes including reservoir curvature, current day stress field, structure pattern, and mechanical stratigraphy. Using the approaches described above, an improved characterization of the fracture system was developed and exported to a geologic model for use in a dynamic simulation model to better predict waterflood performance.


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