Patent ID: 7559369

Claim:
A method of cementing comprising: introducing a cement composition into a subterranean formation, wherein the cement composition consists essentially of: at least one hydraulic cement selected from the group consisting of API Class A Portland cement, API Class C Portland cement, API Class G Portland cement, API Class H Portland cement, a pozzolana cement, a gypsum cement, a high-alumina-content cement, a slag cement, and combinations thereof, water, particulate nano-silica having a particle size in the range of from about 1 nm to about 100 nm and present in an amount in the range of from about 1% to about 25% by weight of the hydraulic cement therein, and at least one additive selected from the group consisting of a strength-retrogression additive, a set accelerator, a weighting agent, a weight-reducing additive, a heavyweight additive, a lost-circulation material, a filtration-control additive, a dispersant, a defoaming agent, a foaming agent, and combinations thereof.