Abstract: Evanescent waveguide sensors for measuring and determining the composition of wellbore fluids in situ are provided. The waveguides are provided on substrates have a thickness and strength sufficient to withstand wellbore pressures and a sufficient surface area to allow for broad range measuring of the wellbore characteristics. The optical sensors facilitate determination of the wellbore fluid composition without requiring in-tool sampling of the wellbore fluid.

Abstract: The method and apparatus of the present invention provides for detecting a flow of a formation fluid entering into a wellbore. An ultrasonic sensor is placed in a wellbore. The sensor has a resonant member that is exposed to a fluid in the wellbore. At a location in the wellbore, acoustic energy is measured wherein the acoustic energy is related to turbulence from formation fluid entering the wellbore. In another embodiment of the invention a tool is provided for detecting a flow of a formation fluid into a downhole location in a wellbore. The ultrasonic sensor has a resonant member that is adapted to be in contact with a fluid in the wellbore. The sensor generates electrical signals when exposed to ultrasonic turbulences caused by a formation fluid entering into the wellbore. A processor processes the electrical signals to detect the flow of the formation fluid entering into the wellbore.

Abstract: Methods and apparatus for downhole analysis of formation fluids by isolating the fluids from the formation and/or borehole in a pressure and volume control unit that is integrated with a flowline of a fluid analysis module and determining fluid characteristics of the isolated fluids. Parameters of interest may be derived for formation fluids in a static state and undesirable formation fluids may be drained and replaced with formation fluids that are suitable for downhole characterization or surface sample extraction. Isolated formation fluids may be circulated in a loop of the flowline for phase behavior characterization. Real-time analysis of the fluids may be performed at or near downhole conditions.

Abstract: A system and method is provided to measure a pressure or other characteristic at a source (e.g. a hydraulic power supply) and in or near a downhole tool. A comparison of the measurements is then made to verify that the system is operating according to desired parameters. In specific applications, the comparison can be made to ensure the supply of hydraulic fluid is reaching the downhole tool.

Abstract: A method for detecting pressure disturbances in a formation accessible by a borehole while performing an operation includes positioning a tool within the borehole, positioning a first probe of the tool at a first location, positioning a second probe of the tool at a second location remote from the first location to obtain a pressure reading, performing an operation with the first probe, detecting the presence of a first phase fluid within the tool, detecting a pressure disturbance within the formation with the second probe, and identifying a second phase fluid based on the detection of the pressure disturbance. Other methods and systems for detecting pressure disturbances in the formation are further shown and described.

Abstract: A downhole load cell calibrated for enhanced accuracy. The load cell may be a dry load cell calibrated by storage of pre-determined temperature and pressure data relative to the load cell based on known loads applied thereto. Thus, surface equipment employed with the load cell may include a computer program that takes advantage of the stored pre-determined information. The computer program may then be employed for calibration of downhole load cell data based on readings from the load cell along with downhole temperature and pressure information.

Abstract: The present disclosure presents illustrative embodiments of a method for estimating the producibility of a hydrocarbon bearing formation using a flexural mechanical resonator to measure the viscosity and density of a representative fluid from the formation. A system is disclosed for estimating the producibility of a hydrocarbon bearing formation using a flexural mechanical resonator to measure the viscosity and density of a representative fluid from the formation. A data structure is disclosed for storing data useful for estimating the producibility of a hydrocarbon bearing formation using a flexural mechanical resonator to measure the viscosity and density of a representative fluid from the formation. The data structure provides a structural and functional interrelationship between the data structure, data in the data structure and a computer and computer software provided in an illustrative embodiment.

Abstract: An apparatus for predicting a downhole viscosity of a treating fluid has an energizer and a viscometer. The treating fluid has a gel. The energizer is capable of energizing a sample of the gel. The viscometer is capable of measuring a viscosity of the energized sample. The viscosity of the sample is predictive downhole viscosity of the treating fluid. The predicted downhole viscosity may be used to improve downhole viscosity. After the downhole viscosity is predicted, a concentration modification fluid can be added to cause the predicted viscosity to approach a desired viscosity.

Abstract: The present invention provides packaging for MEMS devices and other sensors for downhole application. The MEMS devices and/or other sensors may aid in characterizing formation fluids in situ. The packaging facilitates high temperature, high pressure use, which is often encountered in downhole environments.

Abstract: The operation, analysis and interpretation of a chromatographic system can be significantly enhanced by coupling therewith one or more fluid property measurements that provides an initial indication of the fluid type, the presence of any contamination, an estimate of the hydrocarbon composition (C1, C2-C5 and C6+), gas/oil ratio, color and/or fluorescence measurements. Other measurements that can be used in the initial stage can include density, viscosity, phase transition determinations. These measurements may be used to enhance, in real-time, the GC sampling protocol, the analysis protocol and also improve the robustness of the interpretation of the chromatogram.

Abstract: A method and apparatus are provided that assess reservoir compartmentalization by determining whether there are compositional differences such as whether the isotopic ratios of carbon (13C/12C) or of oxygen (17O/18O) are the same or different in various parts of the reservoir. A quartz enhanced photoacoustic spectrometer is provided for analysis of reservoir samples taken in various parts of the reservoir for comparison of geochemical composition to estimate reservoir compartmentalization.

Abstract: A method for the detection of a fluid leak from a plugged well extending from a surface of the earth to penetrate a subterranean formation which contains fluid by logging a collection chamber positioned in the plugged well.

Abstract: In a particular embodiment, a method is disclosed for determining a source of a fluid downhole. The method includes deploying an ion selective sensor downhole, exposing the fluid to the ion selective sensor downhole, measuring an ion concentration at different places within the fluid and using that information to identify a source of the fluid from the ion concentration profile. In another particular embodiment, an apparatus is disclosed for estimating a source of a fluid. The apparatus contains a tool deployed in a well bore, an ion selective sensor in the tool, a processor in communication with the ion selective sensor and a memory for storing an output from the ion selective sensor.

Abstract: A method for testing petroleum or water wells. A tool is secured to a tubing and run into the well and to the reservoir zone to be explored. An upper and a lower seal isolate the reservoir zone. A piston is run into the tubing and pumped down to the tool. When sampling is to take place, a valve is opened and the reservoir fluid, together with drilling fluid filling the well, is allowed to enter the tool while displacing the piston. At the same time, measuring is carried out to identify a tracer added to the drilling fluid. When the tracer no longer can be traced, the drilling fluid contaminated reservoir fluid is displaced out of the tool by the piston and clean reservoir fluid is allowed to enter the tool. The invention also relates to an apparatus for practising the method.

Abstract: The disclosure provides a system, tools and methods for estimating a property or characteristic of a fluid downhole. In one aspect, the method may include: heating the fluid at a selected or first location during a first time phase, taking temperature measurements of the fluid substantially at the selected location during a second time phase, and estimating the property of the downhole fluid using temperature measurements. Temperature measurements may also be taken at a location spaced apart from the first location and used to estimate the property of the fluid. The tool may include a device that heats the fluid during a first time phase and takes temperature measurements of the fluid during a second time phase. A processor uses the temperature measurements and a model to estimate a property of interest of the fluid.

Abstract: A method for analyzing reservoir fluids in connection with a drilling operation includes determining composition and isotopes of injection fluids injected into a wellbore during a drilling operation and production fluids recovered from the wellbore during the drilling operation. Reservoir fluids from a reservoir intersected by the wellbore are characterized based on the composition and isotopes of the injection fluid and of the production fluid.

Abstract: Tracking fluid displacement along a wellbore using real time temperature measurements. A method of tracking fluid displacement along a wellbore includes the steps of: monitoring temperature in real time in the wellbore; and observing in real time a variation in temperature gradient between fluid compositions in the wellbore. Another method of tracking fluid displacement along a wellbore includes the steps of: monitoring temperature along the wellbore; and observing a variation in temperature gradient due to a chemical reaction in the wellbore. Another method includes the step of causing a variation in temperature gradient in the fluid while the fluid flows in the wellbore.

Abstract: Fluid distribution determination and optimization using real time temperature measurements. A method of determining fluid or flow rate distribution along a wellbore includes the steps of: monitoring a temperature distribution along the wellbore in real time; and determining in real time the fluid or flow rate distribution along the wellbore using the temperature distribution. A method of optimizing fluid or flow rate distribution includes the steps of: predicting in real time the fluid or flow rate distribution along the wellbore; comparing the predicted fluid or flow rate distribution to a desired fluid or flow rate distribution; and modifying aspects of a wellbore operation in real time as needed to minimize any deviations between the predicted and desired fluid or flow rate distributions.

Abstract: A single probe system is utilized to quickly obtain uncontaminated formation fluid samples. The single probe includes an outer guard tube and an inner sampling tube which is slightly recessed relative to the outer tube such that the pressure at the front face of the probe is substantially uniform. Each tube is coupled to its own pump which controls the flow rate of the fluid moving through that tube. Knowing the size of the sampling tube relative to the size of the outer probe tube, and optionally based on relative viscosities of formation fluids and filtrates, the pumps are caused to generate a particular flow rate ratio through the tubes such that an appropriate pressure is maintained at the front face of the probe and such that the fluid flowing through the sampling tube is substantially uncontaminated.

Abstract: An apparatus and method for isolating a downhole tool section from hydraulic and mechanical noise. Anchoring grippers are used in conjunction with a fluid diverter valve to anchor the tool section to a borehole wall and divert fluid flowing in the drill string away from sensitive test equipment during formation testing.

Abstract: The outlet pressure of a pump that fluctuates rapidly, as is typical of high pressure multiplex pumps, is sensed in a pressure line leading from the main flow line to a damping mechanism. The damping mechanism comprises a pair of small spaced openings, which are preferably adjustable in size. The damping mechanism is ideally a pair of needle valves placed in series so the pressure downstream of the second needle valve fluctuates considerably less than upstream of the first needle valve. The damped pressure is sensed to provide an input to real time graphs showing various pertinent pressure measurements involving the application of pressure, e.g. to monitor downhole tools in hydrocarbon wells. The downhole tools may be fluid driven motors, whipstocks, packers, wiper plugs and the like. In the case of fluid driven or mud motors, a base line pressure taken when the motor is idling is compared to the pressure when the motor is drilling to detect the onset of motor stall.

Abstract: The present invention relates to a method and apparatus for detection of hydrogen sulfide in downhole operations. A downhole tool is provided with a coupon adapted to react at varying degrees to exposure to concentrations of hydrogen sulfide. The downhole tool is positioned in the wellbore with the coupon(s) exposed to downhole fluids. A reaction to a change in the coupon, such as coloration, is used to determine the presence and concentration of hydrogen sulfide.

Abstract: Flowable devices provide communicate between surface and downhole instruments. The flowable devices having unique addresses are introduced into the flow of a fluid flowing in the wellbore. The flowable devices are used for providing information to a downhole controller and/or retrieving information from a downhole device.

Abstract: A sensing apparatus is provided for use downhole, comprising a housing and sensing means with the housing containing a plurality of separable elements to which data acquired by the sensing means is transferred. The separable elements are releasable from the housing to convey the acquired data to surface. The separable elements have a spherical outer casing of around 1 to 10 cm diameter which surrounds a memory chip. The casing has a sealable aperture so that electrical connection to the chip can be established within the housing.

Abstract: A Vadose Zone Water Fluxmeter (WFM) or Direct Measurement WFM provides direct measurement of unsaturated water flow in the vadose zone. The fluxmeter is a cylindrical device that fits in a borehole or can be installed near the surface, or in pits, or in pile structures. The fluxmeter is primarily a combination of tensiometers and a porous element or plate in a water cell that is used for water injection or extraction under field conditions. The same water pressure measured outside and inside of the soil sheltered by the lower cylinder of the fluxmeter indicates that the water flux through the lower cylinder is similar to the water flux in the surrounding soil. The fluxmeter provides direct measurement of the water flow rate in the unsaturated soils and then determines the water flux, i.e. the water flow rate per unit area.

Abstract: A method of evaluating the volume ratio of gas to oil (GOR) in the fluids of a well during drilling by direct or indirect measurement of the volumes of gas and oil in the cuttings. The method includes determining the volume of gas (Vg) contained in the drilling fluids by measuring a ratio between a volume of gas produced and a corresponding volume of drilled rock, determining the volume of oil (Vo) by measuring the total organic carbon (TOC) in the drilled rock while taking account of physical characteristics of the drilled rock and of the oil under the surface conditions, and determining said volume ratio (GOR) by calculating the ratio of the previously determined volumes of gas and of oil. The method can be implemented in the field, even on a drilling site, using a Rock-Eval type equipment for example.

Abstract: A method is disclosed for downhole determination of the resistivity of fluids from formations surrounding an earth borehole, including the following steps: providing a formation testing logging device that includes a coil and a flow line passing axially through the coil; determining a reference quality factor of the coil; positioning the formation testing device in the borehole, and causing formation fluid to flow through the flow line; measuring the quality factor of the coil with formation fluid in the flow line; and determining the resistivity of the formation fluid in the flow line as a function of the measured quality factor and the reference quality factor.

Abstract: In accordance with a method of this invention, formation integrity problems are discovered, diagnosed and corrected in successively drilled subterranean well bore intervals. If one or more of well bore fluid outflows, formation fluid inflows or inadequate well bore pressure containment integrity are discovered in a drilled well bore interval, well logs are run and other relevant well bore data is collected in the drilled well bore interval and analyzed to provide a specific treatment using a specific pumpable sealing composition for sealing and increasing the pressure containment integrity of the well bore. Thereafter, the sealing composition is pumped into the drilled well bore interval whereby the well bore interval is sealed or the pressure containment integrity is increased, or both.

Abstract: For collecting data from a water well, down-hole sensors are housed in modules. The modules are arranged to be screwed together in-line to form a vertical string. Mechanically, the modules are secured to each other only by the screw connection. Data is transmitted to the surface on a 2-wire cable, there being no other electrical connection between the modules and the surface. The modules are connected in multi-drop configuration to the 2-wire cable. Data is transmitted using time-division multiplexing.

Abstract: The present invention provides a chemometric equation to estimate fluid density, viscosity, dielectric constant and resistivity for a formation fluid sample downhole. The chemometric estimates can be used directly as estimated values for fluid density, viscosity, dielectric constant and resistivity for a formation fluid sample downhole. The chemometric estimates can also be plugged into a Levenberg-Marquardt (LM) non-linear least squares fit, as an initial estimate of the parameter to be estimated by the LM fit. If the initial parameter estimate is too far from the actual parameter values, the LM algorithm may take a long time to converge or even fail to converge entirely. The present invention estimates an initial value of a parameter that provides a high probability that the LM algorithm will converge to a global minimum.

Abstract: An indicator mixture that allows pH measurement over a broader range of pH or to a higher accuracy than available using conventional spectroscopic techniques. In particular, the mixture of the present invention is comprised of two or more reagents such that when combined, the reagent mixture is capable of either detecting: (1) a pH range broader or more accurate than that the reagents individually, or (2) pH more accurately than the reagents individually. Also disclosed are methods of making and using the mixture.

Abstract: The present invention provides an apparatus and method for continuously monitoring the integrity of a pressurized well bore fluid sample collected downhole in an earth boring or well bore. The CDR continuous by measures the temperature and pressure for the down hole sample. Near infrared, mid infrared and visible light analysis is also performed on the small amount of sample to provide an on site analysis of sample properties and contamination level. The onsite analysis comprises determination of gas oil ratio, API gravity and various other parameters which can be estimated by a trained neural network or chemometric equation a flexural mechanical resonator is also provided to measure fluid density and viscosity from which additional parameters can be estimated by a trained neural network or chemometric equation. The sample tank is overpressured or supercharged to obviate adverse pressure drop or other effects of diverting a small sample to the CDR.

Abstract: A method of designing a hydraulic fracturing treatment in a subterranean reservoir comprising the steps of a) quantifying reservoir parameters including the bottomhole temperature and the formation permeability, b) assessing the temporary variation in temperature of the formation due to the injection of a treatment fluid and c) designing a fluid optimized for said temporary temperature.

Abstract: The present invention discloses an acoustic resonator device capable of nucleating bubbles in a formation fluid under borehole-like conditions wherein the static pressure is higher than the bubble point pressure. The device is comprised of one or more coaxial layers forming a central conduit, wherein at least one of the coaxial layers is comprised of an electro-acoustic transducer material such as including piezoelectric or magnetorestrictive materials. This device is preferably designed to be in fluid communication with a host tool to allow in-situ sampling and bubble point determination. Also disclosed is an in-situ method of fluid analysis in a borehole for determining phase characteristics of a formation fluid using the device. Cavitation may be induced using the device in either a captured volume sample or a flow-line sample.

Abstract: Fluid flow properties often dictate the performance of processing operations. The present invention relates to a system for evaluating properties of a fluid flowing in a pipe. A test cell (20) which includes two parallel surfaces (5, 6) which are positioned in the flow. One of the surfaces is moveable relative to the other, to a position in close proximity to the other, to create a stagnant flow region between the surfaces. The system further includes a test input means (10) to apply input motion to one of the surfaces, and a test output means (13) to measure output motions from the cell in response to input motions. Furthermore, the system includes a processing means (9) to calculate rheological parameters of the fluid from signals produced from the test input and test output means. There is also a process for evaluating properties of a flowing fluid.

Abstract: A method for determining the in-situ effective mobility of hydrocarbons in a formation layer, in which a formation test tool, having a fluid analyzer, induces sample fluid to flow from the formation, the sample being analyzed and discarded where it includes fluid from the invaded zone, so as to perform the pressure test on uncontaminated formation fluid.

Abstract: A downhole sub for instrumentation, such as a fiber optic sensor. The sub is configured to be connected to a string of pipe, such as a string of tubing. The sub first comprises an essentially concentric tubular body. The tubular body has an inner diameter that generally conforms to the inner diameter of the tubing string. A recess is formed within the wall of the tubular body. Next, the sub comprises a gauge housing that is received within the recess of the tubular body. The gauge housing includes a plate portion that is exposed to fluids within the production tubing. The gauge housing further includes a side bore that receives a sensor. One or more gauge housing ports are pre-fabricated into the gauge housing to provide fluid communication between the inner bore of the production tubing and the side bore of the gauge housing. The entire sub is preferably self-contained without any elastomers or metal-to-metal seals.

Abstract: The present invention discloses a method and apparatus to detect bubbles in a fluid sample to determine if gases are present, wherein an ultrasonic source is used and its properties monitored. Fluctuations in the ultrasonic source's electrical properties indicate the presence of bubbles/gas. Alternatively, the ultrasonic source may be used to cavitate the sample and induce the nucleation of bubbles. In such a system/method, bubbles may be detected by either (1) monitoring the ultrasonic source properties, (2) monitoring the compressibility of the sample, (3) monitoring the sample properties, including harmonics and subharmonics. The method and apparatus disclosed herein may be used in a borehole such as with a sampling means (including either a flowing sample or a stationary sample) or in a surface lab.

Abstract: A technique that is usable with a subterranean well includes introducing a fluid into the well in connection with a fluid efficiency test. The technique also includes measuring a temperature versus depth distribution along a section of the well in response to the introduction of the fluid.

Abstract: This invention relates to flowable devices and methods of utilizing such flowable devices in wellbores to provide communicate between surface and downhole instruments, among downhole devices, establish a communication network in the wellbore, act as sensors, and act as power transfer devices. The flowable devices are adapted to move with a fluid flowing in the wellbore. The flowable device may be memory device or a device that can provide a measure of a parameter of interest or act as a power transfer device. The flowable devices are introduced into the flow of a fluid flowing in the wellbore. The fluid moves the device in the wellbore. If the device is a data exchange device, it may be channeled in a manner that enables a device in the wellbore to interact with the memory device, which may include retrieving information from the flowable device and/or recording information on the flowable device. The sensor in a flowable device can take a variety of measurement(s) in the wellbore.

Abstract: A method is described for using an electro-rheological fluid as a drilling and completion fluid or as a well service or fracturing fluid. By adjusting the viscosity of the fluid through application of an electrical potential to the fluid, the fluid has enhanced flexibility and multiplicity of purpose over prior art fluids.

Abstract: A method and apparatus for testing formations surrounding an earth borehole. The method includes the following steps: providing a tool movable through the borehole; providing a flow line in the tool; establishing fluid communication between the formations and the flow line of the tool; and providing a sand trap in communication with the flow line of the tool for trapping sand flowing with fluid from the formations.

Abstract: A carrier apparatus for connection with a pipe string for use in transporting at least one gauge downhole through a borehole. The apparatus includes a tubular body for connection with the pipe string having a bore for conducting a fluid therethrough and an outer surface, wherein the outer surface has at least one longitudinal recess formed therein. Further, at least one insert defining an internal chamber for receiving a gauge is mounted with the body such that at least a portion of the insert is receivable within the recess for engagement therewith. The apparatus also includes an interlocking interface comprised of the engagement between the insert and the recess, wherein the interlocking interface is configured such that the insert inhibits radial expansion of the body adjacent the recess. Finally, at least one passage provides fluid communication between the gauge and one of the bore of the body and the borehole.

Abstract: Apparatus for determining the density of a fluid downhole includes apparatus for measuring compressibility of the fluid and apparatus for determining the speed of sound through the fluid. According to the methods of the invention, density of the fluid is calculated based upon the relationship between density, compressibility, and the speed of sound through the fluid.

Abstract: The present invention provides systems utilizing fiber optics for monitoring downhole parameters and the operation and conditions of downhole tools. In one system fiber optics sensors are placed in the wellbore to make distributed measurements for determining the fluid parameters including temperature, pressure, fluid flow, fluid constituents and chemical properties. Optical spectrometric sensors are employed for monitoring chemical properties in the wellbore and at the surface for chemical injection systems. Fiber optic sensors are utilized to determine formation properties including resistivity and acoustic properties compensated for temperature effects. Fiber optic sensors are used to monitor the operation and condition of downhole devices including electrical submersible pumps and flow control devices. In one embodiment, a common fluid line is used to monitor downhole parameters and to operate hydraulically-operated devices.

Abstract: Systems and methods particularly suitable for open hole formation testing are provided. In a described embodiment, a method of performing a test on a formation intersected by a wellbore includes the steps of flowing fluid into an apparatus from the formation, displacing a fluid barrier of the apparatus in one direction, flowing the formation fluid out of the apparatus and back into the formation by applying pressure to the apparatus, and displacing the fluid barrier in an opposite direction.

Abstract: A method of identifying the fluid type of subterranean formations according to the correlation between the variation trend of electrical resistivity with depth downhole in a borehole and the variation trend of porosity with depth downhole in the same borehole. The method includes the steps of: a) determining the rate of change with depth of a resistivity parameter (such as deep resistivity) of the formation surrounding the borehole; b) determining the rate of change with depth of a porosity parameter (such as total porosity and/or free fluid porosity measured by a nuclear magnetic resonance technique) of the formation surrounding the borehole; c) determining a comparison of the rate of change with depth of such resistivity parameter and the rate of change with depth of such porosity parameter for a given depth in the borehole; and d) using the comparison to determine the nature of the fluid in the formation surrounding the borehole at that depth downhole or in a given depth window downhole.

Abstract: An apparatus and method for obtaining samples of pristine formation or; formation fluid, using a work string designed for performing other downhole work such as drilling, workover operations, or re-entry operations. An extendable element extends against the formation wall to obtain the pristine formation or fluid sample. The apparatus includes at least one extendable gripper element for anchoring the apparatus during testing and sampling operations.

Abstract: A pressure self-compensating tensiometer and method to in situ determine below grade soil moisture potential of earthen soil independent of changes in the volume of water contained within the tensiometer chamber, comprising a body having first and second ends, a porous material defining the first body end, a liquid within the body, a transducer housing submerged in the liquid such that a transducer sensor within the housing is kept below the working fluid level in the tensiometer and in fluid contact with the liquid and the ambient atmosphere.

Abstract: A receptacle (10) for use in collecting samples down a well bore (14) is provided, the receptacle comprising a plurality of interconnecting modules (22, 24, 26, 30, 32, 34). A main chamber (22) is capable of holding a sample, and sensors (58, 60, 62, 64) within the chamber detect physical and chemical characteristics of the sample. Valves (50, 52) in a chamber wall seal the chamber (22) after a fluid sample has been collected. A communication means is placed in communication with the chamber (22) so as to provide an externally accessible port which communicates with the inside of the chamber (22) and allows detection and analysis of sample characteristics without removing the sample from the sealed chamber (22). The chamber (22) includes a piston (82) which is adjustable to keep pressure constant in the chamber and a heating element (58) to keep temperature constant. A method for sampling downhole fluids is also provided.