Abstract: A method of stabilizing a clayey geological formation surrounding a hydrocarbon well is described. It comprises the step of treating the formation with a first reactant and a second reactant, characterized in that a reaction of said first and said second reactant is essentially initiated in the presence of clayey material. The reaction can be characterized by substrate intercalation or condensation stabilization with no pH adjustment or stabilization through reaction of glycol with a carbonyl group containing second reactant or a reaction involving an epoxide ring opening under neutral or acidic conditions.

Abstract: A method for continuously mixing a borehole fluid such as cement includes using a measurement of the solid fraction of a cement slurry as it is being mixed to determine the ratio of the solid and liquid components to be added to the slurry. A system for mixing the slurry includes a liquid material (water) supply including a flow meter; a solid material (cement) supply; a mixer which receives the liquid and solid materials and includes an output for delivering materials from the mixer to a delivery system; a device for measuring the amount of material in the mixer; and a flow meter in the output; wherein measurements from the flow meters and the device for measuring the amount of material in the mixer are provided to a control system which provides control signals to automatically control the amount of solid and/or liquid material added to the mixer.

Abstract: A valve for downhole well service, having a rotary indexer carrying an elastically-loaded valve element on a valve seat surface in a flow passage, the valve element adapted to obstruct one or more flow passages in the valve seat surface when aligned therewith. The valve may additionally, or alternatively, comprise an elastically-loaded valve element mounted in one or more flow passages in the valve seat surface, this valve element adapted to obstruct the flow passage in which it is installed when urged into contact with the valve seat surface. When a valve element is mounted in one or more of the flow passages in the valve seat, the indexer comprises a protrusion positioned to engage such valve element and force it out of contact with the valve seat surface. The valve may be actuated by command from the surface by sending telemetry elements to a downhole telemetry data detector.

Abstract: A method and apparatus for estimating sample timing error in discrete multitone modulated signals. An unprocessed measured tone. The phase of the selected measured tone is adjusted using an average phase error. A normalized phase error for the selected measured tone is estimated. The average phase error is updated with the estimated phase error.

Abstract: This invention relates generally to the art of hydraulic fracturing in subterranean formations and more particularly to a method and means for optimizing fracture conductivity. According to the present invention, the well productivity is increased by sequentially injecting into the wellbore alternate stages of fracturing fluids having a contrast in their ability to transport propping agents to improve proppant placement, or having a contrast in the amount of transported propping agents.

Abstract: A tubing conveyed multi-position well treating tool having a tubular housing and a tubular inner member which are relatively positionable at “Set”, “Treat”, “Dump” and “Release” positions actuated by a mechanical indexing mechanism. The indexing mechanism is loaded by a spring, such as a compressed gas spring or mechanical spring, which urges the tubular housing away from the tubing connection of the inner tubular member, thus requiring no set-down forces for tool actuation or indexing. The treating tool is anchored within the well casing by hydraulic pressure actuated buttons, thus eliminating the typical requirement for anchoring actuation by set-down forces. The treating tool is sealed within the casing by pressure energized packers which are activated by the hydraulic pressure of fluid supplied from the tubing. The tool provides a bypass passage to allow communication of the zones above and below the tool while isolating the straddled interval to be treated.

Abstract: A method of determining GOR comprising subjecting a fluid to spectroscopic analysis at a first wavelength sensitive to gas and a second wavelength sensitive to oil, determining a response matrix for the contribution of gas at the first and second wavelengths and the contribution of oil at the first and second wavelengths, determining a signal response vector and the two wavelengths, calculating a mass fraction vector from the response matrix and the signal response vector and using the mass fraction vector to determine GOR.

Abstract: A modular work system permits Rig Up time to be substantially reduced by reducing the number of crane lifts required to offload equipment for a transport boat or vehicle. This is achieved by developing transport skids capable of holding multiple system components. The number of equipment components that must be mechanically coupled on location is reduced by pre-assembling the components and maintaining the assembly in operating condition during storage and transport. Skid design concepts are employed, wherein a skid system carries various pre-assembled components for transport, storage and operation. Specifically, a skid sub-system includes various related components. The components are either pre-assembled or are designed to complete a sub-assembly through final assembly on the rig. The skid is moved into place using the crane, and the assembly is completed. Additional sub-systems are mounted on additional skids which are designed to be mated with the other related skids and sub-assemblies.

Abstract: The present invention provides cementing compositions for an oil well or the like, comprising an hydraulic binder, dense particles with a density higher than the density of the hydraulic binder, and reinforcing particles with a density of less than 1.5 g/cm3, preferably less than 1.2 g/cm3, constituted by a flexible material or rubber, of low compressibility and with an average grain size of less than 600 &mgr;m. The compositions of the invention are of particular advantage when preventing zones which are subjected to extreme stresses, such as perforation zones and the junctions of a multi-branch lateral well. They are also highly suitable for producing plugs.

Abstract: Herein is described a method of completing an interval of a cased well drilled through incompetent formation. This method includes a combination of three successive operations: zero-degree phasing perforation of a relatively small portion of the interval to be completed, consolidation of the formation zone around the perforations and injection of a propped fracturing fluid above fracture pressure to create a gap between the cement and the borehole and pack this gap with a proppant held by a proppant flowback-retention agent.

Abstract: Improved aqueous fracturing fluids are disclosed that are particularly useful as well stimulation fluids to fracture tight (i.e., low permeability) subterranean formations. Gas wells treated with these fracturing fluids have rapid cleanup and enhanced well production. The fluids contain small but sufficient amounts of certain amine oxides to aid in the removal of the fracturing fluid from the formation. By facilitating the removal of fluid from the invaded zones, the amount of damage to the fracture faces in the formation is thereby minimized. The amine oxides correspond to the formula I, wherein R1 is an aliphatic group of from 6 to about 20 carbon atoms, and wherein R2 and R3 are each independently alkyl of from 1 to about 4 carbon atoms.

Abstract: A method for hydraulic fracturing subterranean formation whereby at least part of the fracture is propped with proppant material essentially in the form of elongated particles having a shape with a length-basis aspect ratio greater than 5, preferably such as metallic wire segment. The remaining part of the fracture may be propped with conventional non-metallic proppant. Fracture conductivity is optimized.

Abstract: This invention relates to methods for calibrating a formation permeability model with respect to data obtained from fluid flow measurements. A method according to the invention includes determining a correlation coefficient for a porosity-irreducible water saturation relationship; determining a leading coefficient for a formation permeability model; and determining at least one exponent parameter for the formation permeability model by minimizing a basis function that represents a difference between a formation permeability estimate derived from the formation permeability model and a formation permeability estimate derived from the fluid flow measurements.

Abstract: The combination of the cement contamination laboratory measurements and the field log measurement allows to perform the evaluation of cement placement and quality related to the designed percentage cement displacement coverage and set-up times in the casing annulus. Since the logging time after the cement job is completed is known, a comparison between the acoustic impedance or compressive strength measured using the USI log and the acoustic impedance or the compressive strength measured in the laboratory, a level of mud contamination can be derived at every point across the wellbore. From the laboratory correlations, cement strength prediction with time can be established. This new product will give the operator an accurate tool to recommend performing remedial cementing with a higher success rate.

Abstract: An improved cup packer for use on wellbore tools is disclosed. The open end of the cup packer bore is filled with an elastomer to prevent the intrusion of sand and debris into the space between the cup packer and the wellbore tool on which it is mounted. In an alternative embodiment of the invention, the packer body includes an angularly protruding section at at least one of its ends, wherein the longitudinal dimension of the packer body is at its maximum at its bore. In an additional alternative embodiment of the invention, the open end of the packer is sealed by a screen to prevent the intrusion of sand and debris into the space between the cup packer and the wellbore tool on which it is mounted.

Abstract: Methods for determining the best value for at least one slowness-related parameter that has been determined in a number of ways is disclosed. Sonic logging data input in the methods are processed to determine multiple values of at least one slowness-related parameter using slowness/time coherence (STC) processing methods. The error of each determined parameter is determined and the determined errors used in selecting a representative parameter value from the multiple determined slowness-related parameter values.

Abstract: Coiled tubing (120) is used to drill into a subsurface formation and provide a conduit back to the surface to allow sensors (200) to be deployed and measurements made for monitoring of the formation. A method of monitoring subsurface formation properties between injection and production wells comprises using coiled tubing (120) to drill sensor holes at predetermined positions between the injection and production wells and fixing the coiled tubing permanently in the hole such that a sensor (200) can be deployed in the tubing to provide measurements of the formation.

Abstract: The Invention relates to 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 borehole logging tool system includes a surface system, a logging array, and a logging cable providing power supply and data paths connecting the logging array to the surface system, wherein the logging array includes a series of discrete sondes connected together. The sondes in the logging array, for example a borehole seismic logging array, are connected to their neighbours by means of lengths of logging cable. Such cable can be the same as that connecting the logging array to the surface system. The logging array can also include a master controller module which communicates with the surface system and which includes a first controller module which connects to the surface system and a second controller which controls operation of the sondes in the logging array independently of any other borehole logging tools connected to the surface system.

Abstract: The present invention relates to a method of controlling the quality of seismic data that has been migrated using the generalized Radon transform, the method serving to pass between a seismic data space and a migrated image space, in which method a parameter table is calculated giving, for a seismic wave going from a point of the image to a source or a sensor, its path length, its travel time, and the angles of incidence of the wave at the beginning and at the end of the path, and in which correspondence is established between at least one zone of a first one of said two spaces and at least one zone of the second space, by using said parameter table to fill in a correspondence table QCimage.