Determination of Fractures’ Properties in an Oil Field by Utilizing Estimation Methods

Document Type : Research Paper

Authors

1 Faculty of Petroleum and Gas Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

2 Enhanced Oil Recovery Institute, Tehran, Iran

3 Department of Reservoir Study and Field Development, Research Institute of Petroleum Industry, (RIPI) Tehran, Iran

Abstract

Natural fractures’ network are important in determination of hydraulic behavior of oil and gas reservoirs. Fractures are invaluable in hydrocarbon production, especially in naturally fractured carbonate reservoirs. The effective permeability of Asmari carbonate reservoir is highly dependent on the occurrence of open fractures. In this research, 409 open fractures, derived from image logs of six wells were used to determine fractures’ sets considering Fisher coefficient. The fractures are categorized into seven fractures sets. The variety of fracture sets is an indicator of reservoir heterogeneity. Although the wells are located on the southwestern plunge, the general pattern of fracture in the field is longitudinal. A possible explanation for this phenomenon is change in stress direction during folding. After determination of the fractures’ properties for each fracture set, discrete fracture network model was created. The average orientation of fractures in the test well, which was not used in the DFN model, was identical to the fracture orientation of the DFN model in the location of the well. In the test well, observed reservoir pressure, 2299 psi, (from well test) was matched to the 2294.62 psi of the model.
 

Keywords


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