Evaluation of Cretaceous Sediments Production Index with Petrophysical Data
Gubkin Russian State University of Oil and Gas, Faculty of Petroleum Geology and Geophysics,
Well Logging and Petrophysics Department, Moscow, Russia
Fluid filtration and mass transfer processes description are the key issue of the geological modeling and oilfields development design. The productivity index (PI) indicates mobility of the reservoir fluids and in combination with relative permeability information significantly improves the reliability of field development design. The PI is generally measured during a production test on the well. Several techniques are applied for prediction of the PI from geological and petrophysical data (Darcy’s law, etc.), but all of them are based on the porosity derived permeability, which is usually determined with a high level of uncertainty.
The author of stated work relies on the advanced application of the effective porosity value, which provides description of reservoir properties for dynamic reservoir simulation. The correlation between PI and effective porosity was established from integrated analysis of the production and petrophysical data for 50 wells from Western Siberia. The 3D distribution of effective porosity in combination with relative permeability cube was converted to PI volume. The test data for 25 “blind” wells (not included in modeling process) was used for verification of the productivity index for oil and water distribution in interwell space. The application of Buckley Leverett function gives evaluation of oil and water shares in production.
The new relation between effective porosity and PI is proposed, which goes to the optimization of well placement and oilfield development. The results of stated work are verified with 25 control wells data. Obtained results are applied for fluid filtration processes modeling and reservoir development technology control.
AAPG Search and Discovery Article #90183©2013 AAPG Foundation 2013 Grants-in-Aid Projects