Patent ID: 7550413

Claim:
An aqueous viscoelastic treating fluid comprising: an aqueous base fluid; a viscoelastic surfactant (VES) gelling agent; and an amount of fluid loss control agent effective to improve the fluid loss of the aqueous viscoelastic treating fluid as compared with an identical fluid absent the agent, where the fluid loss control agent is selected from the group consisting of alkaline earth metal oxides or hydroxides selected from the group consisting of oxides or hydroxides of magnesium, calcium, strontium, barium and mixtures thereof; transition metal oxides or hydroxides selected from the group consisting of oxides or hydroxides of vanadium, molybdenum, manganese, iron, cobalt, nickel, palladium, copper, zinc, titanium and mixtures thereof; transition metal hydroxides selected from the group consisting of aluminum, zirconium, tin, antimony and mixtures thereof; and combinations thereof, where the fluid loss control agent has a size ranging from about 1 nanometer to 5 microns.