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 present invention provides cementing compositions for oil wells or the like comprising an hydraulic binder and reinforcing particles constituted by a flexible material of low compressibility, and with an average grain size of less than 500 &mgr;m. The compositions of the invention are of particular advantage when cementing zones which are subjected to extreme dynamic stresses, such as perforation zones and the junctions of a multi-branch lateral well. They are also highly suitable for producing plugs.

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: The improved recovery of hydrocarbons from subterranean formations by hydraulically fracturing a subterranean formation is accomplished. Fracturing fluids using a viscosifying surfactant fluid containing viscosifying micelles, for example, wormlike micelles, are useful to improve recovery of hydrocarbons and limit the loss of fracturing fluid into the formation fracture face. The invention further relates to novel fracturing and acidizing methods useful for increasing hydrocarbon production, limiting water production, resisting fracturing fluid loss into the subterranean formation, and reducing the equipment requirements in mixing and pumping fracturing fluid. The action of viscosifying micelles of surfactant in aqueous zones of the subterranean formation diverts fracturing fluid or acid from the aqueous zones to the hydrocarbon-bearing zones and also facilitates the flowback of increased amounts of hydrocarbons once a fractured well is placed back on production.

Abstract: Herein is described a fluid that is useful in consolidating a formation without the use of a gravel pack and screen. In particular, the fluid is useful in consolidating heterogeneous formations where the permeability is not uniform over-the total formation thickness, e.g. a formation having at least a first layer and a second layer, wherein the permeability of the first layer is greater than that of the second layer. The fluid comprises at least one of a resin, a curing agent, and a surfactant, wherein the fluid is self-diverting. Optionally, a catalyst or other additives, such as an oil wetting agent, can be used. Fluids of the present invention are self-diverting, i.e.

Abstract: A downhole flow control device is provided for remotely controlling fluid flow of production or injection fluids, and may offer the capacity to pass wireline tools therethrough. In a broad aspect, the device may include: a body member having a first bore extending from a first end of the body member and through an extension member disposed within the body member, a second bore extending from a second end of the body member and into an annular space disposed about the extension member, a first valve seat disposed within the first bore, and at least one flow port in the extension member establishing fluid communication between the annular space and the first bore; and a first sleeve member remotely shiftable within the first bore, and having a second valve seat adapted for cooperable sealing engagement with the first valve seat to regulate fluid flow through the at least one flow port.

Abstract: A method of gravel packing a wellbore which has at least one aperture therein that provides a fluid flow path between the wellbore and an adjacent subterranean formation. At least a part of the formation adjacent to the open hole has a filter cake coated thereon that comprises a water and oil emulsion. The method of gravel packing comprises injecting into the wellbore a gravel pack composition that comprises gravel and a carrier fluid. The carrier fluid comprises an aqueous liquid having a pH that is outside the range at which the filter cake emulsion is stable. The aqueous liquid is present in an amount effective to invert the water in oil emulsion in the filter cake when the carrier fluid comes into contact with the filter cake. As a result, gravel is deposited at or adjacent to the aperture in the wellbore and some of the filter cake is removed.

Abstract: Embodiments of the present invention disclose apparatus and methods that can be used to mechanically actuate a downhole tool with an expandable shifting tool. One embodiment of the invention is an expandable shifting tool comprising a housing having an outer diameter and a plurality of radially extendable elements. The radially extendable elements are longitudinally separated from each other and each extendable element is at least partially contained within the housing. The extendable elements are capable of moving between an extended position and a retracted position and are biased towards the extended position.

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.

Abstract: A cementing composition comprising a hydraulic cement powder dispersed in a solvent that is miscible both with water and hydrocarbons to make a slurry. The cement powder can be made up simply of hydraulic cement materials or can be a mixture of such materials with particles that are inert or reactive with cement. The composition can also include surfactants or retarders. The composition is used to plug water production in a well while leaving hydrocarbon production unaffected.

Abstract: The effect of various chemical or biological agents in well treatment fluids can be delayed by sequestering the agents in the discontinuous phase of an emulsion for a period of time, before the emulsion is destabilized by exposure to at least one of: (1) a change in temperature, (2) a change in pH, (3) a change in salinity, (4) a change in alcohol concentration, (5) a change in stabilizing surfactant concentration, (6) a change in organic ion concentration, (7) a change in destabilizing surfactant concentration, (8) a change in surfactant adsorbent material concentration, (9) an ultrasonic pulse, and (10) an electrical field. Upon exposure to the emulsion destabilizing condition, the agent sequestered in the discontinuous phase of the emulsion is released into the continuous phase of the fluid composition, where it can have its intended effect.

Abstract: An annular pack for a cylindrical member for use in a wellbore includes a housing adapted to be mounted about an exterior circumference of the cylindrical member. The housing has mutually engagable annular segments. At least one of the annular segments defines a chamber for housing an electrical device.

Abstract: Non-aqueous base wellbore fluids characterized by enhanced electrical conductivity due to formulation with specified ionic liquids are disclosed. Drilling, completion, and workover methods utilizing the wellbore fluids are also disclosed.

Abstract: A tool activating system includes a multiple control units coupled to activate devices in a tool string positioned in a well. A processor is capable of communicating with the control units to send commands to the control units as well as to retrieve information (such as unique identifiers and status) of the control units. Selective activation of the control units may be performed based on the retrieved information. Further, defective control units or devices may be bypassed or skipped over.

Abstract: Herein is disclosed a well completion or stimulation fluid, comprising (i) a carrier fluid; (ii) a viscoelastic surfactant; and (iii) a fluid loss control additive (FLA) comprising at least one polymer and at least one crosslinker. The fluid may further comprise proppant or gravel, if it is intended for use as a fracturing fluid or a gravel packing fluid, although such uses do not require that the fluid comprise proppant or gravel. Also disclosed herein are methods of fracturing a subterranean formation, comprising (i) providing a fracturing fluid discussed above and (ii) injecting the fracturing fluid into the formation at a pressure sufficiently high to fracture the formation. In addition, disclosed herein are methods of gravel packing a wellbore, comprising (i) providing a gravel packing fluid discussed above and (ii) injecting the gravel packing fluid into the wellbore.

Abstract: The invention provides a method of fracturing, including the provision and use of a fracturing fluid suspension containing an effective amount of a solid particulate breaker material having delayed breaking or degradation characteristics, additionally including an amount of durable fibers and/or platelets sufficient to enhance wellbore solids, such as proppant, transport. In a preferred aspect, solid particulate matter, which comprises or is composed of a specified organic polymeric compound or composition having an average molecular weight of at least 10,000, or a mixture of such compounds or compositions, and which solid organic polymeric matter reacts or decomposes, as described, is combined in a fracturing fluid with or containing a specified gellant and proppant, to form a fracturing fluid suspension, and the suspension formed is pumped downwell and deposited as a gelled suspension in the subterranean formation, generally under fracturing conditions.

Abstract: A perforating device has a carrier strip (e.g., a linear strip) on which are mounted capsule charges arranged in a desired pattern. The pattern can be a phased pattern, such as a spiral pattern, a triphase pattern, and so forth. Alternatively, the pattern is a 0°- or 180°-phased pattern for performing oriented perforating, with the capsule charges shooting in opposite directions with respect to a desired plane in the formation of the wellbore. One or more brackets can be used to mount the capsule charges to the strip. In one arrangement, the bracket has plural support rings to connect to the capsule charges. In another arrangement, multiple brackets each holding one or more capsule charges may be employed. In yet another arrangement, a tube containing the capsule charges in a phased arrangement can be used. In a further arrangement, instead of using brackets, threaded openings are provided in the carrier strip in which capsule charges can be threadably connected to provide the desired phased pattern.

Abstract: A tool string for use in a well includes a filter sub (or trapped pressure regulator sub) that is used with other components to reduce trapped pressure. The filter sub filters out debris that may occur from various types of downhole operations, such as perforating operations. By filtering out larger debris, only gases, liquids, and smaller particles are allowed to enter various components of the tool string. Without the presence of larger solid debris inside certain components of the tool string, the likelihood of plugs being formed is reduced so that gases and liquids can more readily pass out of the tool string as the tool string is retrieved to the surface of the well and the well hydrostatic pressure decreases.

Abstract: The present invention provides a water-based fluid, in particular for drilling, completion or for any other intervention in a well such as a hydrocarbon well, in which the viscosity is controlled by a system constituted by precipitated silica nanoparticles (A) associated with a water-soluble copolymer (B) comprising one or more water-soluble co-monomers (I) having little or no affinity for silica and one or more co-monomers (II) which absorb onto the silica. The invention is of particular application to the secondary recovery of hydrocarbons.