The System of Adaptive Well Log Data Interpretation in Geological Modeling

Wide spread application of 3D geological modeling, oil and gas field development practices resulted in substantiation of the necessity for transition from the traditional concept of “absolute pore volume” to the concept of “effective pore volume”. This could be achieved with the geophysical and logging data algorithms interpretation and procedures system directed to the determination of reservoirs dynamic characteristics with high vertical resolution united with principles of adaptability and petrophysical invariance of reservoirs. Adaptive petrophysical models make possible the quantitative estimation of effective porosity and effective/phase permeability. Formation parameters, which characterize the content of bound water in the matrix and cement, maximum possible total porosity and effective porosity, relations between effective porosity and effective permeability are estimated according to outcomes of petrophysical modeling. Effective porosity is calculated with the standard logs data interpretation. The distribution of reservoir properties in three-dimensional space is carried out with geostatistical simulation techniques. Application of effective porosity to prediction of relative permeability and capillary pressures with log data was realized as an important task for field development design. The test of the proposed technology is conducted on a large number of wells worldwide. Formations consist of clastic fine-grained sandstones with complex cement mineral composition.