Methods for treating intervals of a subterranean formation having variable permeability

A method of treating an interval of a subterranean formation having a first portion with a first water permeability and a second portion with a second water permeability wherein the first water permeability is not the same as the second water permeability, the method comprising:

• contacting the first portion and the second portion of the interval with a water-soluble hydrophobically modified polymer capable of selectively reducing the effective permeability of the portion to water without a comparable reduction of the effective permeability of the interval to hydrocarbons,
• wherein the hydrophobically modified polymer modifies both the first water permeability and the second water permeability to a more uniform, third water permeability, and the third permeability of the interval to water is different from the first permeability by an amount up to about 40%;
• and
• treating the interval with a treatment fluid, wherein the first portion and the second portion both exhibit a more uniform, third permeability, thus allowing for a more uniform treatment of the interval by the treatment fluid than would be allowed without treatment of the interval with the hydrophobically modified polymer.