Abstract: Well completion foamed spacer fluids and methods of using the foamed spacer fluids are provided. A method of the invention for displacing a first fluid from a well bore with an incompatible second fluid comprises the following steps. A foamed spacer fluid is placed between the first and second fluids to separate the first and second fluids and to remove the first fluid from the walls of the well bore. Thereafter, the first fluid and the foamed spacer fluid are displaced from the well bore with the second fluid.

Abstract: Improved methods of coating dry proppant particles with a hardenable resin composition, suspending the coated proppant particles in a fracturing fluid and consolidating the proppant particles after being placed in fractures into high strength permeable masses are provided. As the fractures are formed, a liquid hardenable resin component is continuously mixed with a liquid hardening agent component on-the-fly to form a hardenable resin composition. The hardenable resin composition is continuously coated onto dry proppant particles conveyed from a source thereof on-the-fly to form resin composition coated proppant particles, and the resin composition coated proppant particles are continuously suspended in the fracturing fluid on-the-fly.

Abstract: Methods for cementing a pipe string in a well bore containing oil-based drilling fluid using oil-based settable spotting fluid compositions are provided. The oil-based settable spotting fluid compositions basically comprise an oil external emulsion comprising oil, water and an emulsifying surfactant; a hydraulically settable component; and a de-emulsifying surfactant for de-emulsifying the oil-external emulsion when the emulsion is cured.

Abstract: Methods for drilling well bores and cementing a pipe string in the well bores using oil-based settable drilling fluids are provided. The oil-based settable drilling fluid compositions basically comprise an oil external emulsion comprising oil, water and an emulsifying surfactant; a hydraulically settable component; and a de-emulsifying surfactant for de-emulsifying the oil-external emulsion when the emulsion is cured.

Abstract: Methods of forming a permeable cement composition in a well bore adjacent to a fluid producing zone therein and cement compositions for forming permeable cement sand screens in well bores are provided. A cement composition of the invention is comprised of a hydraulic cement, a particulate cross-linked aqueous gel having a size in the range of from about 100 microns to about 3000 microns containing an internal temperature activated breaker, a particulate dehydrated cross-linked aqueous gel having a size in the range,of from about 40 microns to about 500 microns containing an internal temperature activated breaker and water present in an amount sufficient to form a slurry.

Abstract: The present invention provides particulate flow enhancing additives for improving the flow properties of dry particulate cementitious materials. The particulate flow enhancing additives basically comprise a particulate solid adsorbent material having a flow inducing chemical adsorbed thereon.

Abstract: The present invention provides methods, lightweight well cement compositions and additives for the well cement compositions. The methods of the invention for sealing pipe in a well bore penetrating a zone or formation which readily fractures at low hydrostatic pressure is basically comprised of the steps of providing a lightweight cement composition comprised of a hydraulic cement, water and an additive comprising a suspension of microspheres in water gelled with sodium bentonite, placing the cement composition in the annulus between the pipe and the well bore and allowing the cement composition to set.

Abstract: An acidizing composition and a method of acidizing a hydrocarbon bearing subterranean formation in the presence of ferric ions are provided. The acidizing composition includes a mineral acid solution, an electron donor agent, a primary electron transfer agent and a secondary electron transfer agent. The primary electron transfer agent is a source of vanadium ions. The secondary electron transfer agent is a source of iodide ion or iodine. The electron donor agent and primary and secondary electron transfer agents function together to reduce ferric ion present in the mineral acid solution to ferrous ion which in turn prevents ferric hydroxide and/or free sulfur from precipitating out of the solution and reduces the formation of sludge in crude oil in the formation.

Abstract: The present invention provides methods, lightweight well cement compositions and additives for the well cement compositions. The methods of the invention for sealing pipe in a well bore penetrating a zone or formation which readily fractures at low hydrostatic pressure is basically comprised of the steps of providing a lightweight cement composition comprised of a hydraulic cement, water and an additive comprising a suspension of microspheres in water gelled with sodium bentonite, placing the cement composition in the annulus between the pipe and the well bore and allowing the cement composition to set.

Abstract: Storable water-microsphere suspensions for use in well cements and methods of cementing well bores are provided. The storable water-microsphere suspensions are basically comprised of water, microspheres and an effective amount of a suspending agent selected from the group consisting of microfine or colloidal materials and gel forming polymers.

Abstract: Methods and compositions for cementing subterranean zones penetrated by well bores are provided. The methods are basically comprised of the steps of providing a cement composition which comprises a hydraulic cement, sufficient water to form a slurry and a dispersing agent comprising a tetrapolymer formed of methacrylic acid, methacrylate, methallyl sulfonic acid and ethoxylated acrylic acid. The cement composition is placed in the subterranean zone to be cemented and allowed to set into an impermeable solid mass therein.

Abstract: The present invention provides stable well cementing methods and compositions for sealing subterranean zones penetrated by well bores. The improved thermally stable and degradation resistant well cement compositions are basically comprised of a hydraulic cement, sufficient water to form a pumpable slurry, an aqueous hydrogenated styrene-butadiene rubber latex and a latex stabilizer present in an amount sufficient to stabilize the hydrogenated styrene-butadiene latex.

Abstract: The present invention provides seawater-based cross-linked fracturing fluids and methods of preparing and using the fluids in fracturing subterranean formations penetrated by well bores and having temperatures above about 200° F. The improved cross-linked fracturing fluids are basically comprised of a gelling agent, seawater present in an amount sufficient to hydrate the gelling agent and to form a gelled aqueous fluid, and a delayed cross-linking agent, capable of causing delayed cross-linking of the gelling agent in the gelled aqueous fluid at a pH below the threshold for precipitate formation in seawater.

Abstract: The present invention provides methods, lightweight well cement compositions and additives for the well cement compositions. The methods of the invention for sealing pipe in a well bore penetrating a zone or formation which readily fractures at low hydrostatic pressure is basically comprised of the steps of providing a lightweight cement composition comprised of a hydraulic cement, water and an additive comprising an aqueous suspension of microspheres containing a water swellable clay suspending agent, placing the cement composition in the annulus between the pipe and the well bore and allowing the cement composition to set.

Abstract: The present invention provides improved compositions and methods for cementing casing strings in deep water offshore formations penetrated by well bores. The cement composition basically comprises hydraulic cement, water, an environmentally degradable water reducing and dispersing additive, an environmentally degradable set retarding additive and an environmentally degradable compressive strength and set accelerating additive.

Abstract: Environmentally acceptable well cement fluid loss control additives, cement compositions including the additives and methods of using the compositions are provided. The environmentally acceptable fluid loss control additives are comprised of ethoxylated hydroxyethylcellulose having a reduced molecular weight.

Abstract: Methods and compositions for sealing subterranean zones penetrated by well bores are provided. The methods basically comprise the steps of introducing a sealing composition into the subterranean zone comprised of a hydraulic cement, sufficient water to form a slurry and a rapidly acting thixotropy providing gelling agent, and allowing the sealing composition to remain at rest in the zone whereby the sealing composition rapidly gels and then sets into a hard impermeable mass therein.

Abstract: Methods of preparing a particulate flow enhancing additive are provided. The methods are basically comprised of preparing a particulate flow enhancing additive for improving the flow properties of particulate cementitious materials comprising adsorbing a flow inducing chemical on a particulate solid adsorbent material.

Abstract: Delayed thixotropic cement compositions and methods of cementing in subterranean zones penetrated by well bores are provided. The novel cement compositions are basically comprised of a hydraulic cement, sufficient water to form a slurry and a water soluble delayed thixotropy imparting additive selected from the group consisting of carbonic acid and alkali metal carbonates.

Abstract: Methods of drilling well bores using an invertible oil external-water internal emulsion drilling fluid and then inverting the drilling fluid to a water external-oil internal emulsion are provided. The methods basically comprise the steps of contacting the oil external-water internal emulsion with an aqueous acid solution containing an anionic sulfonate surfactant for preventing aqueous acid solution-crude oil emulsions and crude oil sludging and a chemical for preventing the anionic sulfonate surfactant from reacting with the emulsifier in the oil external-water internal emulsion.