Online Journal for E&P Geoscientists

Kozhevnikov, Dmitry A.¹; Kovalenko, Kazimir ¹; Deshenenkov, Ivan S.^*1
(1) Well Logging, Gubkin Russian State University of Oil and Gas, Moscow, Russian Federation.

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.

The adaptive log data interpretation technology provides analytical relations between log interpretative parameters and reservoir rocks properties in the generalized form. Proposed interpretative algorithms are implemented in the geological modeling software package and combined with standard geological modeling procedures to develop the three-dimensional distribution of reservoir properties.

Adaptive petrophysical models make possible the quantitative estimation of effective porosity and effective/phase/relative 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 (spontaneous potential log, compensated neutron log, formation density log, acoustic log and gamma-ray log). 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 (Western & Eastern Siberia, Caspian region, Middle East, Alaska). Formations consist of clastic fine-grained sandstones with cement and matrix complex mineral composition.

Application of proposed technology in geological modeling software packages represents an innovative direction of geological information technologies, focused on the geological interpretative intelligence systems development (methodological, petrophysical, interpretative and algorithmic). It doesn’t require any special capital expenditure with a significant economy of forces and operational time.