Abstract: The authors of the paper investigate IPN,606,612 precross linked gel particles' distribution of blank off coefficient in fractured core,meanwhile, study these gel particles' blank offrate, reserve rate and the gradient of particles' break through pressure in the fractured core after 4, 10, 30, and 180 hours respectively. The results of the experiment show that gel particles' distribution of blank off coefficient and their dynamic law in the fractured core can be used to evaluate the particles' migration law and profile control property in the fractured core. It is also identified IPN gel particles illustrate a good blankoff effect. When IPV water is injeceted, the blank off coeficient of long fractured core is quite steady, which is apparentely higher than that of 606 and 612 gel particals. The blank off rate in the fractured core after 180 days can reach 90.3 percent and the reserve rate of blankoff water efficiency 99 percent. This kind of gel can be used as a deep profile control agent in the channeling reservoirs.

Key words: IPN gel particles, fractured core, blankoff coefficient, blankoff rate, reserve rate, breakthrough pressure gradient of the particle, profile adjusting, experiment.