Accurate Lithology and Porosity Prediction using Simultaneous Angle Stack Inversion on the Shtokman Field

Studying the Shtokman field which is unique both in terms of its estimated reserves and quality of its gas bearing reservoirs leads to a number of specific geological problems. Accurate prediction of reservoir properties from seismic data is interfered here by extremely high values of gas saturation imprinting all dynamic parameters of seismic record. This makes lithological classification of a section and evaluation of reservoir properties quite tricky. Solution of the problem can be delivered with the use of simultaneous angle stack inversion which allows to recover from seismic data a set of independent elastic parameters providing a multi-dimensional domain for further detailed lithology analysis. After that it is possible to accurately evaluate reservoir properties for each litho-type.