Geological Characteristics of the Potential Injection Production Dominant Channel in Marine Sandstone Reservoir—Taking Donghe Sandstone in Tarim Basin for Example

Compared to the eastern sandstone reservoir, the internal interbed of marine sandstone reservoir is not continuous, so interlayer channeling and water cut are rising fast after long-term water flooding. Interlayer channeling is too serious to lead to the complex relation between oil and water movement, so the injection production dominant channel identification is more difficult than that of the eastern sandstone reservoir, but up to now the identification of this kind of reservoir is so rare. At present, the development of this kind of reservoir is just step into the middle or high water-cut stage, and the remaining reserves potential is huge, so accurately and efficiently identified and characterized of dominant channel has the vital significance for subsequent efficiently development of marine sandstone reservoir. In this paper, based on the marine sedimentary facies of Donghe sandstone in Tarim basin, using pair well method of core analysis, the pressure displacement experiment and core thin section observation, through comparing the reservoir property changes of different stages of waterflooding involving reservoir permeability, pore throat structure, in-layer heterogeneity, and shale content, obtain the geological characteristics of the potential injection production dominant channel in marine sandstone reservoir. The application result proved the research could judge the potential injection production dominant channels of different well groups and layers from the aspect of static geological characteristics, and has a good consistency with the dynamic development characteristics.