Methods for making and using retarded acid compositions for well stimulation

A method of treating a subterranean formation penetrated by a wellbore, the method comprising:

• utilizing a composition comprising a first concentration of an acid, a surfactant, and a second concentration of an acid retarding agent (RA) comprising at least one salt compound;
• contacting the subterranean formation with the composition over a period of time at a pressure higher than a fracture initiation pressure of the subterranean formation to fracture and treat the subterranean formation;
• measuring at least one parameter of the subterranean formation while the composition is in contact with the subterranean formation, resulting in at least one dynamic parameter value, wherein the at least one parameter comprises temperature of the subterranean formation, or pressure of the subterranean formation, or both;
• and
• reducing the second concentration of the RA relative to the first concentration of the acid in the composition within the subterranean formation during the period of time from the second concentration of the RA to a third concentration of the RA lower than the second concentration of the RA based on the at least one dynamic parameter value.