Abstract:

By using the core analysis data before polymer injection and after polymer breakthough from two wells in the polymer-injection area of Block 1,the central Gudao,the change patterns of reservoir parameters after a long-term polymer drive are compared and discussed.It is suggested that the long-term polymer drive has resulted in enlarging some small pore throats,improving the communication among pores and reducing pore tortuosity in the reservoirs.For the microscopic parameters of the reservoirs,the maximum,average,and normal pore-throat radiuses increased,the expulsion pressure,the mercury 50% saturation pressure and the variation coefficient decreased,and the mean coefficient rised.For the macroscopic reservoir parameters,the permeability was enhanced,and the porosity variation was within the range of allowable error.

Key words: petrophysical parameter, polymer drive, pore texture, permeability, Block1 in the central Gudao, Jiyang Depression