Abstract: Based on the data of core analysis, the relationship between the permeability and median radius of porosity in the conglomerate reservoir in Karamay field is established. Integrated with the relations of relative molecular mass of several polymers with suitable pore sizes given by filter membrane experiment, the method for selection of relative molecular mass of plymers by polymer flooding process in conglomerate is proposed. It is shown from this study that the polymer flooding of T1k1 of East District 7 (1) in conglomerate reservoir in Karamay field should be performed by the relative molecular mass of 2 500×104 of polymer. This method could be as a guide for the polymer choice of other conglomerate reservoirs.

Key words: conglomerate reservoir, polymer, relative molecular mass, method