For sandstone reservoirs after polymer flooding

the selection of saturation interpretation models as well as their parameters depends on whether electric characters and parameters of the reservoirs change with the adsorption and retention of polymer. Based on experiment measurements of resistivity of reservoir rocks after flooded by polymer solutions of different concentration and salinity

we studied the influence of polymer flooding on rock resistivity and various indexes

and came to a conclusion that when the salinity is greater than 4 000mg/L

the polymer solution has a relative small impact upon the resistivity (only 5.8% as polymer concentration increases from 0 to 3 000 mg/L) and various indexes

and thus can be ignored during logging interpretation. The study laid down a sound foundation for a better interpretation of saturation after polymer flooding.