Applications of facies-controlled nonlinear random inversion for carbonate reservoir prediction in Block A of Amu-darya Basin
ZHANG Zhi-wei1, WANG Chun-sheng1, LIN Ya-ping1, ZHOU Tian-wei1, HUANG Han-dong2, ZHAO Di2
1 Research Institute of Petroleum Exploration and Development,PetroChina,Beijing,100083;
2 College of Earth Resources and Information,China University of Petroleum,Beijing,102249,China
Abstract：Focus on carbonate reservoir characteristics sensitive to P-wave attributes in Block A of Amu-darya Basin,we picked the velocity,amplitude and frequency from 3D seismic data constrained by geological and logging data,and then we applied facies-controlled nonlinear random inversion for carbonate reservoir prediction in Block A of Amu-darya Basin.The following observations were obtained.First,carbonate rocks have bedded features in Block A of Amu-darya Basin.Two strong reflections were found at the top and the bottoms of carbonate rocks.Reflections are continuous in intervals.Carbonate reservoirs are mainly porous with few caves but very few fractures.Secondly,carbonate reservoirs are mainly shown as low velocity zones,located the southeast and northeast in the study area.Low velocity zones on the structure crest are favorable drilling location.Thirdly,different lithology is shown as different velocity on inversion sections.The velocity of the upper clastic rock is the lowest,and the velocity of the anhydrite and salt rocks in the middle is higher than the upper clastic rock.And the velocity of the underlying clastic rock is higher the upper one.The velocity of the carbonate reservoir is highest.Two wells drilled on the favorable location predicted by the facies-controlled nonlinear random inversion produce large-duty gas.This demonstrated that the facies-controlled nonlinear random inversion is accurate and reliable.
