This method can be utilized not only to calculate effective permeability of oil or water phase of each producing oil zone of oil wells, but also to estimate effe.

For condensate gas reservoirs producing below the dew-point pressure,condensate accumulates near wellbore,blocking flow channels of condensate gas and decreasing gas effective permeability and productivity.

For the condition of seldom core wells and none single-zone well test, it is presented that using the combination of well test and pro- duction well log data for many layers to be tested together to estimate oil/water effective permeability, and thus to calculate water saturation based on the empirical relationship of relative permeability and water saturation from core experiment.

Finally,the evolution of crack hydraulic aperture is studied,which is responsible for the variations of the critical water head pressure gradient,inherent permeability and quadratic term coefficient.

Practice in production of ultra-low permeability reservoirs indicate that it is difficult to evaluate the reservoir production performance with conventional development index effectively,so,the effective flooding permeability is introduced,and research shows the fluid can flow in the sublayers whose permeability is greater than the limit.