AN EXPERIMENT STUDY ON MEASURING MINIMUM STARTING PRESSURE FOR LOW PERMEABILITY RESERVOIR

Based According to the characteristics of fluid flow in low permeability reservoir,a method was designed that unsteady displacement-capillary measurement determines the minimum starting pressure gradient of low-permeability core.Using the natural low permeability reservoir rocks from Xinjiang Oilfield,the minimum starting pressure of water,oil at irreducible water saturation and initial period of displacement of oil by water were investigated respectively.The result show that when the viscosity of water and oil remained unchanged,the relationship of starting pressure and the gas permeability can be described by power exponential function.The minimum starting pressure of cores can be determined by this experiment method and it has the virtue of operation,short measuring time,accurate date,application,etc.