Abstract: Subterranean formation treating fluid concentrates, treating fluids and methods are provided by the present invention. The treating fluid concentrates are basically comprised of water and a substantially fully hydrated depolymerized polymer. The treating fluids which are formed by adding water to the treating fluid concentrates are basically comprised of water, a substantially fully hydrated depolymerized polymer and a crosslinking agent for crosslinking the hydrated depolymerized polymer.

Abstract: A method of modifying the structural integrity of material in a subterranean earth situs. The method comprises the steps of mechanically digging into the situs to break the material into pieces and, simultaneously, hydraulically admixing a modifying agent with the pieces by introducing the modifying agent into the pieces at a velocity in the range of from about 300 ft./sec. to about 2500 ft./sec. The method is particularly suitable for improving the strengh and load-bearing capacity of material in a subterranean earth situs. Also provided is a method of modifying the stuctural integrity of material in a subterranean earth situs and installing a pre-formed structural element therein.

Abstract: A precipitation control additive composition, an acidizing composition for treating a sour well and a method of treating a sour well are provided. An iron sequestering agent, such as aminopolycarboxylic acids, hydroxycarboxylic acids, cyclic polyethers, and derivatives thereof and a sulfide modifier, such as aldehyde, acetal, hemiacetal, and many other compounds capable of forming aldehydes in solution are added to a treating solution. The iron sequestering agent cobines with iron present in the solution while the sulfide modifier combines with sulfides present in the solution. By combining with both iron and sulfides present in the solution, the combination of an iron sequestering agent and a sulfide modifier effectively inhibits precipitation of ferric hydroxide, ferrous sulfide and free sulfur from the solution. As a result, formation and other serious damage is prevented.

Abstract: The present invention provides methods of controlling the growth of one or more vertically oriented fractures in a subterranean formation during a fracturing treatment. A first fluid having a known density and containing a diverting agent is introduced into a formation to create a fracture. A second fluid which may contain proppant and having a known density different from the first fluid then is introduced into the fracture whereby the second fluid selectively overrides or underrides the first fluid. Such fluid control forces the first fluid to the bottom or top of the fracture whereby the diverting agent therein is caused to screen out and impede further downward or upward growth of the fracture. The introduction of the second fluid then can be continued to extend the fracture as desired.

Abstract: An improved method and composition for reducing the production of sludge when contacting a subterranean formation containing oil which is subject to sludging with an aqueous acid solution. An anti-sludging agent and one or more other additives are combined with the aqueous acid solution along with a dispersing agent which forms the aqueous acid solution and additives into a long-term homogeneous composition.

Abstract: Methods and compositions are provided for consolidating solids, either existing or placed in subterranean zones. The solids are contacted with a low viscosity aqueous carrier fluid having an acid curable resin dispersed therein and a delayed acting acid catalyst dissolved therein. The delayed acting catalyst is comprised of the reaction product of an acid and an alkali metal or ammonium molybdate.

Abstract: High strength, chemical resistant particulate solids are provided which are particularly suitable for use in treating subterranean zones penetrated by well bores such as for forming gravel packs, as fracture propping agents and as cement composition structural fillers. The high strength, chemical resistant particulate solids are formed by coating solids with the reaction product of an organofunctional silane and an aryl acid halide.

Abstract: Methods of sealing particular areas, including subterranean well formations, are provided wherein the methods utilize an isocyanate polymer suitable as a sealing agent having a controllable gelation time in the presence of water without formation of excess foam by using one or more typical di- or polyisocyanates with one or more alcoholic or acidic compounds and a particular catalyst namely, triethylene-diamine, Groups 3 and 4 metal-organic compounds or mixtures thereof. A particularly useful catalyst is tributyl titanate.