Most scholars believe the existence of starting pressure,thinking of the threshold pressure resulted from the abnormal of fluid boundary zone properties,non-Newtonian fluid and the lagging of oil-gas phase permeability.But the abnormal of fluid boundary layer properties have been proven to be negative by chemical experts;Small part of scholars believe that there is no threshold pressure,and the illusion of starting pressure existing is because of the respond process of rock strain,the limit of experimental ...