Abstract: A non-acetylated but otherwise unmodified xanthan heteropolysaccharide polymer plus guar gum, is employed to impart viscosity to an aqueous particle transport fluid (such as a drilling fluid, a fracturing fluid, or a filter structure emplacement fluid) sufficient to suspend mineral particles. A cross linking agent can also be employed to decrease the amounts of xanthan heteropolysaccharide polymer and guar gum which are needed for particle suspension.

Abstract: The present invention provides a single trip system for placing perforating apparatus and sand control equipment in a wellbore. This system includes a casing string equipped with extendible pistons and a pumpable activator plug for extending the pistons. Additionally, this system utilizes a single gravel-pack and completion tool string. Further, this system includes a means for opening the extendible pistons to fluid flow.

Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises an organic titanium complex. The composition further contains an organic hydroxycarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably less than 5. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 to about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: A fracturing fluid based on quar gum exhibiting good viscosity and stability at temperatures from about 80.degree. C. to at least about 120.degree. C. The fracturing fluid includes a guar gum, a zirconium or hafnium cross-linking agent, and a bicarbonate salt in an aqueous solution at a pH from about 8 to about 10.

Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises a metal compound, preferably an organic metal complex, and most preferably an organic zirconium complex. The composition further contains an organic hydroxycarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably no more than 4.8. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 and about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: Various organometallic crosslinkers containing titanium or zirconium atoms in the +4 oxidation (valence) state have been used to crosslink solvatable polysaccharides (e.g., hydroxypropyl guar) in aqueous media. The crosslinked gels are useful as fracturing fluids. Aqueous solutions of the organometallic crosslinkers are stabilized against deterioration upon storage by adding an alkanolamine (e.g., triethanolamine). Additionally, the alkanolamines also stabilize the crosslinked gels against shear degradation at elevated temperatures.

Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises a metal compound, preferably an organic metal complex, and most preferably an organic zirconium complex. The composition further contains an organic hydroxymonocarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably less than 4.8. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 and about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises an organic titanium complex. The composition further contains an organic alpha-hydroxymonocarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably less than 5. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 and about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: Various organometallic crosslinkers containing titanium or zirconium atoms in the +4 oxidation (valence) state have been used to crosslink solvatable polysaccharides (e.g., hydroxypropyl guar) in aqueous media. The crosslinked gels are useful as fracturing fluids. Aqueous solutions of the organometallic crosslinkers are stabilized against deterioration upon storage by adding an alkanolamine (e.g., triethanolamine). Additionally, the alkanolamines also stabilize the crosslinked gels against shear degradation at elevated temperatures.

Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises a metal compound, preferably an organic metal complex, and most preferably an organic zirconium complex. The composition further contains an organic hydroxymonocarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably no more than 4.8. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 and about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises an organic titanium complex. The composition further contains an organic hydroxycarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably less than 5. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 and about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: A digital weather radar system having a mode that clears the display of all clutter and lighter precipitation to reveal or positively present only the contoured areas, i.e., the severe "cores" or "hard spots." Data representative of the searched space is stored at least temporarily in a digital memory. In the preferred embodiment, a controllable decoder operates on this data according to the particular decoder state selected, the decoder output is D/A converted, and the resultant analog signal is used to intensity modulate a cathode ray tube (CRT).