Abstract: A process for fracturing a subterranean formation surrounding a gas or oil well which comprises:(a) injecting into said subterranean formation under hydraulic pressure a fluid comprising a solution of terpolymer dissolved in a solvent system, said solvent system comprising an organic liquid and a polar cosolvent, said polar cosolvent being less than about 15 weight percent of said solvent system, said terpolymer comprising a water-insoluble, oil-soluble terpolymer dissolved in said solvent system, the concentration of said terpolymer in said solution being about 0.2 to about 10 weight percent and the viscosity of said solution being less than about 2,000 cps, said terpolymer having the formula: ##STR1## wherein R.sub.1 =C.sub.6 H.sub.5, C.sub.6 H.sub.4 --CH.sub.3, C.sub.6 H.sub.4 --(CH.sub.3).sub.3, Cn H.sub.

Abstract: An aqueous slurry which comprises (a) a cement; (b) about 0.05 to 5.0 wt. % of a copolymer of N-vinylpyrrolidone and a salt of styrenesulfonic acid based on the dry weight of said cement; (c) about 0.05 to 5.0 wt. % of a formaldehyde condensed naphthalene-sulfonic acid salt based on the dry weight of said cement; and (d) water, said cement, said copolymer and said dispersant being dispersed in said water to form said aqueous slurry.

Abstract: A method of completing a subterranean formation of an oil or gas well to increase the recovery of hydrocarbons from the producing reservoir which comprises dissolving about 0.25 to about 20 lb/bbl of a water soluble terpolymer in an aqueous solution to viscosify said aqueous solution and pumping said aqueous solution with said water base terpolymer dissolved therein into said well to control the sub-surface pressures of said well, wherein said terpolymer has the formula: ##STR1## wherein x is about 70 to about 98 mole %, y is about 1 to about 15 mole %, z is about 1 to about 15 mole %, wherein y and z are less than 60 mole %, and M is selected from the group consisting of amines and a metallic cation being selected from the group consisting of lead, iron, aluminum, Groups IA, IIA, IB and II of the Periodic Table of Elements.

Abstract: Copolymers of a predominant proportion of an olefinically unsaturated sulfonic acid, an acrylamide, a vinyl phosphonic acid, and optionally other copolymerizable vinyl monomers, form aqueous acid gel compositions when added to the aqueous acid along with a gelling agent selected from titanium or zirconium compounds, and retarded gel destabilizing compounds containing fluoride, sulphate or phosphate anions, the apparent viscosity and time of stability of the acid gel composition being controlled by the addition of these essential ingredients.

Abstract: A process for fracturing a subterranean formation surrounding a gas or oil well which comprises injecting into said subterranean formation under hydraulic pressure a fluid comprising about 0.01 to about 25 weight percent of a water insoluble polymer complex dissolved in a solvent system of a nonpolar organic liquid, said polymer complex comprising the interaction product of a metal neutralized sulfonated polymer and an amine containing polymer, wherein the sulfonate content of the sulfonated polymer is about 4 meq. per 100 gram of polymer to about 200 meq. per 100 gram of polymer and the basic nitrogen content of the amine containing polymer is about 4 meq. per 100 gram of polymer to about 500 meq. per 100 gram of polymer.

Abstract: A process for fracturing a subterranean formation surrounding a gas or oil well which comprises injecting said subterranean formation under hydraulic pressure with a fluid comprising about 0.1 to about 75 percent of an interpolymer complex dissolved in a solvent system of a nonpolar organic liquid and a polar cosolvent (as desired), said polymer complex comprises the interaction product of a sulfonated polymer and an amine containing polymer, wherein the sulfonate content of the sulfonated polymer is about 4 meq. per 100 gram of polymer to about 200 meq. per 100 gram of polymer and the basic nitrogen content of the amine containing polymer is about 4 meq. per 100 gram of polymer to about 500 meq. per 100 gram of polymer, and by the addition of polar cosolvent to such solution of polymer complex modifying its rheological properties over a wide range and their subsequent use as fracturing fluids.

Abstract: An oil-based drilling mud which comprises:(a) a hydrocarbon liquid substantially immiscible in water;(b) about 1 to about 100 parts by weight of water per 100 parts of the hydrocarbon liquid;(c) about 2 to about 50 lb/bbl. of at least one emulsifier;(d) about 0.5 to about 5 lb/bbl. of a wetting agent;(e) about 50 to about 750 lb/bbl. of a weighting agent;(f) about 0.1 to about 25 lb/bbl. of a water insoluble, oil soluble terpolymer, said terpolymer having the formula: ##STR1## wherein R.sub.1 and R.sub.3 are selected from the group consisting of hydrogen and a methyl group, wherein R.sub.2 is selected from the group consisting of C.sub.3 H.sub.5, C.sub.6 H.sub.4 --CH.sub.3, C.sub.6 H.sub.4 (CH.sub.3).sub.2 and CnH.sub.2n+1, wherein n=1 to 30 and R.sub.4 is selected from the group consisting of C.sub.5 H.sub.4 N, CnH.sub.2n NH.sub.3 and CnH.sub.2n N(CH.sub.3).sub.

Abstract: An oil-based drilling mud which comprises an organic liquid substantially immiscible in water; about 1 to about 10 parts by weight of water per 100 parts by weight of the organic liquid; about 20 to about 50 lb./bbl. of at least one emulsifier; weighting material necessary to achieve the desired density; and about 0.25 to about 4.0 lb/bbl. of a hydrocarbon soluble polymeric complex formed from a water insoluble anionic polymer and a cationic polymer.