Patent ID: 7521398

Claim:
A method comprising conducting drilling or completing operations in a subterranean well that penetrates through one or more subterranean formations containing a shale which swells in the presence of water, wherein the conduct is carried out in the presence of a well bore fluid, wherein the well bore fluid includes: an aqueous based continuous phase; and a shale hydration inhibition agent having the formula: in which R and R′ independently selected from hydrogen, methyl, ethyl or propyl, R″ is a bridging group having 1 to 20 carbon atoms and n has a value from 1 to 4 and X is an amine, hydroxyl, alkoxy, carboxy group, in which at least one of the amine functional groups have been reacted with a predetermined amount of C1 to C25 carboxylic acid; and wherein the shale hydration inhibition agent has a concentration range from about 0.5 to about 20 pounds per barrel.