Abstract: Liquids comprised solely of anions and cations (“ionic liquids”) are disclosed as novel components of fluids (and techniques relying upon those fluids) for stimulation of hydrocarbon wells. In particular, the fluids disclosed are useful in matrix acidizing. Formation of the ionic liquids of the present Invention is highly exothermic, hence the heat generated can be used, for instance, to melt de-watered drilling fluid in the near-wellbore region of the formation. Further, reaction of the ionic liquids with water results in acid generation; this acid can be used to, for instance, to stimulate a formation, either by conventional matrix acidizing or fracture acidizing. In addition, certain preferred species of the ionic liquids of the present Invention are highly stable solvents, hence they can be used as carrier fluids for highly reactive super acids (e.g., SbF5+HF) in connection with matrix acidizing.

Abstract: In one embodiment, the invention relates to a method for location, or location and entry, of a lateral wellbore from a main wellbore of a multilateral hydrocarbon well, the method being characterized by unique operation of a controllably bent sub. The invention further relates to a system for location, or location and entry of a lateral wellbore, including a specialized controllably bent sub, and most preferably, to a controllably bent sub designed for efficient lateral wellbore location and/or entry.

Abstract: The improved recovery of hydrocarbons from subterranean formations by fracturing and matrix acidizing a subterranean formation is accomplished. Well treatment fluids having a viscoelastic surfactant fluid containing worm like micelles are useful to improve recovery of hydrocarbons and limit the loss of fracturing fluid into the formation fracture face. The viscolastic surfactant-based fracturing fluids of the present Invention are stable across a wide pH spectrum, allowing them to be used for fracturing treatments at low pH, as well as matrix acidizing treatments. In addition, the stability of these fluids is enhanced in the presence of organic anions. Two-stage fracturing treatments comprised of a viscoelastic surfactant-based fracturing fluid and a polymer-based system, wherein the two fluids are either blended or pumped into the formation sequentially (the polymer last) are also presented.

Abstract: The present Invention relates to hydrocarbon well stimulation, and more particularly to methods and compositions to remove (or more generally to transfer) fluid introduced into the subsurface. For instance, preferred methods involve creating then exploiting a capillary pressure gradient at the fracture face to induce fluid flow from the fracture into the formation thereby increasing effective fracture length, and then improving fracture conductivity.

Abstract: The Invention relates to novel fluids and techniques to optimize/enhance the production of hydrocarbon from subterranean formations (e.g., "completion fluids"), in particular, fluids and techniques are disclosed and claimed which remove wellbore damage and near-wellbore damage in the form of coating formed from drilling and production-related operations ("filtercake"); the techniques can be applied either by themselves or in conjunction with other completion operations, such as gravel packing; preferred embodiments are chelating agent and enzyme systems in a viscoelastic surfactant (VES) matrix.

Abstract: A system and method is disclosed for generating an oriented three-dimensional graphical representation of a borehole. A system is implemented for receiving oriented caliper and borehole trajectory data taken by a 4-arm (or more) caliper device relating to a borehole. This information is used to generate an oriented three-dimensional wire mesh model of the borehole and color map the generated three-dimensional wire mesh model using the caliper data and gamma ray (or other lithology indicator) to reflect one or both of the orientation of borehole ellipticity or the lithology of the borehole.

Abstract: Methods and processes are claimed for optimal design of hydraulic fracturing jobs, and in particular, methods and processes for selecting the optimal amount of proppant-carrying fluid to be pumped into the fracture (which is a crucial parameter in hydraulic fracturing) wherein these design parameters are obtained, ultimately from a priori formation/rock parameters, from pressure-decline data obtained during both linear and radial flow regimes, and by analogy with a related problem in heat transfer, in addition the claimed methods and processes also include redundant verification means.

Abstract: The present Invention relates to hydrocarbon well stimulation, and more particularly to methods and compositions to remove (or more generally to transfer) fluid introduced into a subsurface fracture, in which the methods involve creating then exploiting chemical potential gradients at the fracture face to induce fluid flow from the fracture into the formation; the methods and compositions involve creating, or relying upon an intrisic or previously created, a selectively permeable membrane that is permeable to water but that does not allow solutes to pass through.

Abstract: Products and methods relating to composite materials and their use in coiled tubing is disclosed. The composite tubing is a pressurized means of conveying fluids downhole in a wellbore. It includes a multilayered laminate that resists buckling within the wellbore and is fabricated into a hollow tube. The fibers are oriented in angular relationship to the longitudinal direction of the coiled tubing such as to provide appropriate strength and buckling characteristics to the coiled tubing. Further, the coiled tubing layered laminate may transmit signals representing data from downhole to the surface. In some embodiments, a composite disconnecting device which includes a blend of fibers of different types or orientations is shown. The disconnecting device shows a failure load range corresponding to the failure characteristics of the fiber blend, the fiber blend having a predetermined failure limit.

Abstract: The present invention concerns a cementing composition for an oil (or similar) well, based on an aluminous hydraulic cement, fine particles, hollow microspheres, water in a quantity such that the porosity is in the range 25% to 50%, a dispersing agent, a setting accelerator for the aluminous cement and optionally, other conventional additives. The invention is of particular application to cementing conductor pipes in arctic zones or in deep-water wells.

Abstract: The crosslinking of galactomannan gum fracturing fluids by borate ion is delayed for high temperature applications by completing boron in a basic solution with an organic polyol. Low pumping friction pressures are achieved by the delay in the crosslinking with the boron being available at high temperatures to add high temperature stability to the fracturing fluid at temperatures ranging upto about 300.degree. F.

Abstract: Novel abrasive particles for cleaning subterranean wellbores are described. The particles are rounded, preferably spherical, and has a hardness of 80 to 200 Vickers. The particles are preferably made of non-metallic material such as Calcite pellets. The new abrasives cause significantly less damage to the well tubulars than sand.

Abstract: A composition adapted to form a strengthened gel for treating subterranean formations is described, the composition comprising an aqueous liquid containing an effective amount of a water soluble crosslinkable polymeric gel forming material and a crosslinking agent in an amount sufficient to crosslink said material, and a gel strengthening amount of an inert colloidal particulate material. A method for forming a strengthened gel in at least a portion of a subterranean formation is also disclosed, the method comprising injecting into at least a portion of a formation an aqueous liquid gel forming composition of the type described, and allowing the aqueous liquid composition to form a strengthened gel.

Abstract: A method of predicting a desired property, such as thickening time, of a cement slurry comprising measuring or determining other properties of a slurry composition and obtaining a predicted value of the desired property by applying values representative of the other properties to a model formed by determining the other properties for a series of cement compositions and correlating these with measured values of the desired property. In one embodiment the method comprises measuring and determining the other properties and inputting values corresponding to these properties to a neural network device configured to output a value representative of the desired property, the neural network device being a) configured to utilize each of said values as input values, b) provided with at least one hidden layer of at least one node, and c) trained with a dataset comprising series of values of said properties and a value corresponding to the desired property when measured for a slurry having the measured properties.

Abstract: A well logging fluid is provided having a relatively non-conductive fluid and an effective amount of an electrically conductive fiber sufficient to modify the electrical characteristics of the relatively non-conductive fluid resulting in a modified fluid or well logging fluid such that an electrical well-logging tool when disposed in the modified fluid can perform an electrical well-logging survey of a borehole containing the modified fluid. The non-conductive fluid is selected from the group consisting of a non-aqueous fluid and an invert emulsion of an aqueous phase in a non-conductive liquid. In an invert emulsion, the aqueous portion thereof ranges up to about 70 percent by volume. Preferably, the modified fluid or well logging fluid has an electrical stability of at most 350 volts, more preferably at most 250 volts, as measured according to API RB 13-2. The well logging may be used for electric well logging and imaging.

Abstract: A system for isolating a production pipeline string from the flow of fluids includes an isolation pipe string assembly. The isolation pipe string assembly is positioned by a shifting collet assembly so that in a first position fluids are allowed to the well bore through a sand control production screen. The shifting collet assembly is then used to position the isolation pipe string assembly in a second position wherein seals are placed both above and below the sand control production screen so that fluids are not allowed to re-enter the well bore.

Abstract: Methods and apparatus are disclosed for fracturing subterranean formations using fracturing fluids that are hydrated from dry mix blends. One aspect of the invention comprises a dry blended particulate composition for hydraulic fracturing comprising a particulate hydratable polysaccharide, a particulate crosslinking agent, and a slowly releasing particulate base. The compositions employ controlled release methods of particle dissolution. The invention reveals a dry blended particulate composition capable of significantly improved high temperature stability. Further, methods of fracturing and apparatus for rapidly hydrating and pumping the fracturing fluid into subterranean formations are disclosed.

Abstract: A method is provided for limiting the inflow of formation water during a well turn around to maximize polymer recovery after a hydraulic fracturing treatment of a formation. The method includes a step for selectively blocking the pore structure in a water-bearing zone and not blocking the pore structure of a hydrocarbon zone at the formation face; performing a hydraulic fracturing treatment using a fluid having a polymer; and turning the well around to recover the polymer. There is also provided a method of acidizing, preferably matrix acidizing, a formation having a hydrocarbon zone and a water-bearing zone. The method includes a step for selectively blocking the pore structure in the water-bearing zone at the formation face to selectively retard migration of acid into the water-bearing zone; and injecting acid into the formation, wherein the acid is diverted from the water-bearing zone to the hydrocarbon zone as a result of the selective blocking step.

Abstract: A chemical system and method to stop or minimize fluid loss during completion of wells penetrating hydrocarbon formations are provided. The inventions relates to formulating a highly stable crosslinked hydroxyethyl cellulose (HEC), control released viscosity reduction additives, and user friendly packaging. The chemical system contains a linear HEC polymer solution, a low solubility compound which slowly raises the fluid pH, a chelating agent which further increases the pH level beyond the equilibrium achievable by the low solubility compound, a metal crosslinker which crosslinks HEC at elevated pH, a crosslink delaying agent which allows fluid viscosity to remain low until the fluid reaches the subterranean formation, and optionally an internal breaker. The chemical additives are packaged as an integrated pallet and transported to a field location which allows operators to conveniently mix them before pumping.

Abstract: Apparatus and method for pulling or inserting jointed pipe sections (18) having upset ends (20) within a well utilizing a coiled tubing injector (26). The coiled tubing injector (26) has a pair of opposed endless chains (50, 52) including gripper blocks (58) for gripping the pipe sections (18). An axial gap (G) is provided in chains (50, 52) between adjacent gripper blocks (58) to receive the upset ends (20). To align accurately upset ends (20) with gap (G), a sensing mechanism (100, FIGS. 11 and 12) is provided to sense the location of upset end (20) and a sensing mechanism (110, 112, FIGS. 13 and 14) is provided to sense the location of gap (G). An operator in response to signals from the sensors accurately aligns upset ends (20) with gap (G).