Patent ID: 8316941

Claim:
A method of treating a sandstone-containing formation penetrated by a wellbore, the method comprising: forming a treatment fluid comprising an aqueous fluid containing a Bronsted acid, a hydrogen fluoride source and an organic acid or salt thereof that is substantially soluble in the aqueous fluid, the fluid containing less than about 2% of fluoride (F − ) by weight of the fluid and from 2% or less of sodium (Na + ) by weight of the fluid, wherein the treatment fluid has a pH of about 6 or less; introducing the treatment fluid into the formation through the wellbore as a single-stage without introducing an acid-containing fluid preflush into the formation prior to introducing the treatment fluid; and shutting in the fluid into to the formation for about 2 hours or more, prior to flowing back the treatment fluid to the surface, wherein the combination of Bronsted acid/organic acid or salt thereof is present in the treatment fluid in an amount sufficient to keep at least 5000 ppm Ca2+ in solution.