injection wells to reduce the potential risk of pushing amorphous silica and other solids towards the near wellbore region where it has a more damaging effect than when pushed deeper into the formation addition of chemical additives to the acid can be used to modify the morphology of the deposited amorphous silica to enable faster dissolution during the alkaline stage in particular the use of nucleation inhibitors that cause smaller particles to form with a higher specific surface area are expected to increase the dissolution rate during the alkaline stage and shut in addition of chemical additives to the spacer can be used to minimize the risk of scale formation when fluid mixing occurs the use of chelants to prevent the formation of scales containing di and trivalent cations but other chemicals could be used as well chelants have proven useful in moderately and slightly acidic stimulation fluids but they are even more effective at alkaline conditions polymers may also be selected to improve displacement of acid residue surfactants may be added to impart preferential wetting viscoelastic surfactants may be added optionally to impart viscosity in some embodiments tracer species may be introduced in each fluid stage to allow tracking of fluid placement and timing of injection of the subsequent stages the preferred fluids may also include other additives common in fluids used in subterranean stimulation including bactericides corrosion inhibitors and inhibitor aids clay stabilizers shale stabilizers demulsifiers and scale inhibitors for example the alkaline stage of the treatment has a consolidating effect as an additional benefit the treatment can be designed to improve consolidation in poorly.