Abstract: Unconsolidated formation sand in the near wellbore region may be uniformly consolidated using a system including a sodium silicate solution and a hardener, such as at least one dialkyl ester of a dicarboxylic acid. Subsequently, a low concentration acid, such as hydrofluoric (HF) acid, is pumped through and into the consolidated sand to create channels or passageways to connect the formation hydrocarbons with the wellbore for production of the hydrocarbons through the wellbore. Hydrofluoric acid may be generated in situ by hydrolyzing a substance to hydrofluoric acid where the substance may include ammonium bifluoride, ammonium fluoride, alkali metal fluorides, alkali metal bifluorides, transition metal fluorides, and the like, and mixtures thereof. The acid may instead or additionally include organic acids and other mineral acids.

Abstract: An aqueous, viscoelastic fluid gelled with a viscoelastic surfactant (VES) is stabilized with an effective amount of an alkaline earth metal oxide alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides transition metal oxides, transition metal hydroxides, post-transition metal oxides, and post-transition metal hydroxides. These fluids are more stable and have a reduced or no tendency to precipitate, particularly at elevated temperatures, and may also help control fluid loss. When the particle size of the magnesium oxide or other particulate agent is a nanometer scale, for instance having a mean particle size of 100 nm or less, that scale may provide particle charges that use chemisorption, “crosslinking” and/or other chemistries to associate and stabilize the VES fluids, and also help trap or fixate formation fines when deposited into a proppant pack in a fracture.

Abstract: A combined electromagnetic acoustic transducer (EMAT) is disclosed adapted to generate both SH-type acoustic waves and LAMB-type acoustic waves in a conductive casing, surroundings of which are to be analyzed. The transducer comprises one magnet assembly and two RF coils implemented as multi-layer printed circuit board. Each coil is used to generate or receive acoustic signals of one wave type. Compared to using two single-wave-type transducers the combined EMAT significantly reduces total attraction force to the casing and, correspondingly, simplifies mechanics of the measurement tool. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: Measurements made by a four terminal resistivity imaging tool in a borehole using a voltage measurement device with two different input impedances. From the two measurements, formation resistivity is determined with minimal sensitivity to standoff.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a synergistic internal breaker composition that contains at least one first internal breaker that may be a mineral oil and a second breaker that may be an unsaturated fatty acid. The internal breakers may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. This combination of different types of internal breakers break the VES-gelled aqueous fluid faster than if one of the breaker types is used alone in an equivalent total amount.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of an internal breaker composition that contains at least one mineral oil, at least one polyalphaolefin oil, at least one saturated fatty acid and/or at least one unsaturated fatty acid. The internal breaker may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. In one non-limiting embodiment, the internal breaker, e.g. mineral oil, is added to the fluid after it has been substantially gelled. An oil-soluble surfactant is present to enhance or accelerate the reduction of viscosity of the gelled aqueous fluid.

Abstract: 1st order free-surface multiples recorded in VSP data or reverse VSP data are processed using a 3-C 3-D vector migration method to produce an image of the subsurface. This image produces a larger coverage than that obtained in 3-C 3-D processing of reflection data acquired in the VSP.

Abstract: Single phase microemulsions improve the removal of filter cakes formed during drilling with invert emulsions. The single phase microemulsion removes oil and solids from the deposited filter cake. Optionally, an acid capable of solubilizing the filter cake bridging particles may also be used with the microemulsion. In one non-limiting embodiment the acid may be a polyamino carboxylic acid. Skin damage removal from internal and external filter cake deposition can be reduced.

Abstract: An electrochemical noise method, apparatus and system calculates parameters of interest related to corrosion rates of an electrically conductive article. The method involves placing a test electrode, a reference electrode, and an auxiliary electrode in an environment of interest; placing the test electrode under potentiostatic control regime for a potential scan; measuring the relationship of current v. potential (polarization resistance, Rp) of the test electrode relative to the reference electrode during a first period; switching from potentiostatic control to the open circuit potential (OCP) of the test electrode; monitoring the OCP of the test electrode during a second period; determining ?I from the relationship Rp=?V/?I, where ?V is measured over a second period of time; and calculating the localized corrosion from the measured potential and current data.

Abstract: A coring device includes a primary and a secondary bit that drill a first and second depth into a formation, respectively. The first and second bits are positioned on telescopically arranged mandrels that are rotated by a suitable rotary drive. The coring tool also includes a drive device that extends the first bit and the second bit a first depth into the formation and extends only the second bit a second depth into the formation. In arrangements, the actuating device can include a first hydraulic actuator applying pressure to extend the second bit into the formation and a second hydraulic actuator applying pressure to retract the second bit from the formation. The advancement and retraction of the first and second bits can be controlled by a control unit that uses sensor signals, timers, preprogrammed instruction and any other suitable arrangement.

Abstract: The present invention provides a downhole spectrometer for determination of dew point pressure to determine an associated optimal pumping rate during sampling to avoid precipitation of asphaltenes in a formation sample. A sample is captured at formation pressure in a controlled volume. The pressure in the controlled volume is reduced. Initially the formation fluid sample appears dark and allows less light energy to pass through a sample under test. The sample under test, however, becomes lighter and allows more light energy to pass through the sample as the pressure is reduced and the formation fluid sample becomes thinner or less dense under the reduced pressure. At the dew point pressure, however, the sample begins to darken and allows less light energy to pass through it as asphaltenes begin to precipitate out of the sample. Thus, the dew point is that pressure at which peak light energy passes through the sample.

Abstract: Oxazolidinium compounds are formed by the reaction of a halohydrin or an epoxide with a secondary amine and an aldehyde or a ketone. The oxazolidinium compounds are formed directly and do not require the reaction of a pre-formed oxazolidine with an alkylating agent. The compounds are useful as gas hydrate inhibitors in oil and gas production and transportation.

Abstract: Clean-up additive compositions may be used to enhance the clean-up of VES-gelled aqueous fluids in a wide range of applications and VES fluid compositions, including use of an internal breaker system. The compositions are microemulsions that may include, but not necessarily be limited to, at least one viscosity reducing agent, at least one solubilizing agent, at least one desorption agent and at least one water wetting agent. One non-limiting embodiment of a specific microemulsion includes an unsaturated fatty acid oil, a glycol, a sorbitan ester/ethoxylated sorbitan ester mixture, and an alkyl sulfonate. Microemulsions may perform one or more of the following functions: keeping the reservoir water wet; keeping surface tension reduction low; demulsifying reservoir crude oils and aqueous VES fluids; dispersing and solubilizing the by-products generated when breaking the VES gel; and/or limiting the amount of VES residue on reservoir minerals.

Abstract: A cyclone separator (40) includes a housing (42), in which a cyclone assembly (10) is contained. The housing (42) has an inflow chamber (44), an overflow chamber (46) and a discharge chamber (48). The cyclone assembly (10) has an inner cyclone liner (16) positioned concentrically within a cyclone chamber (12). A displacement means (52) is provided for displacing the inner cyclone liner (16) axially from an operative position in the cyclone chamber (12) to an inoperative position in the overflow chamber (46) of the housing (42). The cyclone chamber (12) has a larger internal diameter than the inner cyclone liner (16), therefore, when the inner cyclone liner is moved to the inoperative position, the flowrate through the cyclone assembly is increased.

Abstract: The corrosion inhibitor blend of at least one corrosion inhibitor base (which may be a Mannich reaction product), a solvent selected from the group consisting of C1 acids and ester and salt derivatives thereof, and optionally a surfactant, has been found to be effective as a corrosion inhibitor for metals in acid media, particularly fluids containing halogen acids. The corrosion inhibitor has improved performance over similar or identical corrosion inhibitor compositions where an alcohol such as methanol is used as a solvent. Suitable, non-limiting possibilities for the solvent include, but are not necessarily limited to formic acid, formate salts, methyl formate, ethyl formate, benzyl formate, formate salts of amines, inorganic formate, and mixtures thereof.

Abstract: A connector for a downhole tool includes a body with one or more conductors positioned at least partially axially adjacent to an axial bore that extends at least partially through the body. In embodiments, one or more seals surrounding the body prevent fluid from flowing from a lateral opening into the interior of the downhole tool. Additionally, the body of the connector can include a circumferential or annular recess that acts as a reservoir to contain or capture fluid that might otherwise enter the sub. Leak protection can also be protected by applying a pressure compensating material around the body.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a composition that contains at least one unsaturated fatty acid, such as a monoenoic acid and/or polyenoic acid. The unsaturated fatty acid may be contained in an oil-soluble internal phase of the fluid. The breaking composition is believed to act possibly by rearranging, disaggregating or otherwise attacking the micellar structure of the VES-gelled fluid. In a specific, non-limiting instance, a brine fluid gelled with an amine oxide surfactant can have its viscosity broken with an oil such as flax (linseed) oil, soybean oil and/or fish oils containing relatively high amounts of unsaturated fatty acids. The unsaturated fatty acids are thought to auto-oxidize into products such as aldehydes, ketones and saturated fatty acids that break the VES gel.

Abstract: A cyclonic flotation system may be used to separate oil, grease, solids and other suspended matter from produced water by a combination of flotation and centrifugation in a separator cyclone. The cyclonic flotation system has a higher capacity-to-footprint ratio compared to conventional apparatus resulting in reduced weight and cost. The system is motion independent and suitable for use on floating structures such as offshore platforms and vessels.

Abstract: Gas hydrate formation in a well completion fluid in the annular space of a hydrocarbon producing well may be controlled by the incorporation of effective amounts of one or more low dose gas hydrate inhibitors, including but not limited to, low dosage hydrate inhibitors (LDHIs), kinetic hydrate inhibitors, dendrimeric or branched compounds, linear polymers and copolymers and onium compounds.

Abstract: An isolation device operatively coupled to a wellbore tool is activated upon receiving fluid that a predetermined applied pressure. When the fluid string reaches the predetermined applied pressure, the isolation device undertakes a specified action such as longitudinal movement, rotation, expansion, etc. that actuates or operates the wellbore tool. Premature actuation of the wellbore tool is prevented by applying a resistive force to the isolation device that, alone or in cooperation with another mechanism, arrests movement of the isolation device. This resistive force is generated by applied pressure of the fluid in the work string.