Abstract: Mixtures of fibers and solid particles are effective for curing fluid losses and lost circulation in a subterranean well. Stiff fibers are more effective than flexible ones; however, mixtures of stiff and flexible fibers have a synergistic effect. The quantity and particle-size distribution of the solids are optimized according to the stiffness, dimensions and concentrations of fibers.

Abstract: Mixtures of fibers and solid particles are effective for curing fluid losses and lost circulation in a subterranean well. Stiff fibers are more effective than flexible ones; however, mixtures of stiff and flexible fibers have a synergistic effect. The quantity and particle-size distribution of the solids are optimized according to the stiffness, dimensions and concentrations of fibers.

Abstract: A method of stabilizing an underground formation surrounding a borehole comprising placing a treatment fluid in the formation, the treatment fluid comprising cross-linkable polymer and a cross-linking agent, and allowing the treatment fluid to gel in-situ, characterized in that after placement of the treatment fluid in the formation, an activator fluid is pumped into the well to bring about cross linking of the polymer to form the gel.

Abstract: In a process to design high temperature cement sluries, the temperature stable phases (anorthite, wairakite) are selected; aluminum modifiers and silica oxides are added to the dry cement so that the elemental composition of the blend corresponds to the phases selected; the control of the particle size distribution and the relative amount of those minerals allow their addition at high concentration while leaving the slurry easily mixable and pumpable; and the kinetics of the targeted phases formation is then controlled by adjusting the crystallinity and the particles sizes of the different solids.

Abstract: A method of stabilising an underground formation surrounding a borehole comprising placing a treatment fluid in the formation, the treatment fluid comprising cross-linkable polymer and a cross-linking agent, and allowing the treatment fluid to gel in-situ, characterised in that after placement of the treatment fluid in the formation, an activator fluid is pumped into the well to bring about cross linking of the polymer to form the gel.

Abstract: In a process to design high temperature cement sluries, the temperature stable phases (anorthite, wairakite) are selected; aluminum modifiers and silica oxides are added to the dry cement so that the elemental composition of the blend corresponds to the phases selected; the control of the particle size distribution and the relative amount of those minerals allow their addition at high concentration while leaving the slurry easily mixable and pumpable; and the kinetics of the targeted phases formation is then controlled by adjusting the crystallinity and the particles sizes of the different solids.