a composition of matter wherein amino resins such as melamine formaldehyde resins modify biopolymers thereby forming gels with transitional metal ions useful for profile control where said polymers have amine , amide , hydroxyl and thiol functionalities . said gels are thermally stable , brine tolerant and rehealable . said resin modified biopolymers can be used in their liquid or ungelled state as a mobility control agent in a reservoir during the removal of hydrocarbonaceous fluids therefrom .