Abstract: A method of determining a concentration level of a compound in a mixture is provided. A plurality of compounds are identified in the mixture based on intensity peaks identified from NMR data generated from the mixture. A compound is selected from the identified plurality of compounds for a concentration determination. A concentration equation associated with the selected compound is determined. A first peak associated with the selected compound is selected from the NMR data. The selected first peak does not overlap with a peak associated with another compound of the identified plurality of compounds. An intensity value associated with the selected first peak is determined. A concentration of the selected compound in the mixture is calculated using the determined concentration equation and the determined intensity value.

Abstract: A method of measuring the compressibility, and/or the density, of small particles, and especially nano-particles, in suspension is described. The static method uses steady pressures and measures the d-c (static) compressibility of particles. The ultrasonic method utilizes an ultrasonic pulsed doppler system to measure the compressibility of particles at ultrasonic frequencies, which may differ from static values. These methods can also be used together to provide overlapping and complementary information about the particles. In addition, the ultrasonic pulsed doppler system also provides a way to measure particle density.

Abstract: A method for estimating a viscosity of a fluid in a rock formation, the method including: performing a first nuclear magnetic resonance (NMR) measurement with zero magnetic field gradient on at least a portion of a sample of the rock formation to obtain a first distribution of transverse relaxation time constants; estimating a first diffusive couple factor from the first distribution; replacing the fluid of the at least a portion of the sample with another fluid; performing a second NMR measurement with zero magnetic field gradient on the at least a portion of the sample containing the another fluid to obtain a second distribution of transverse relaxation time constants; estimating a second diffusive couple factor from the second distribution; and estimating the viscosity of the fluid using the first diffusive couple factor and the second diffusive couple factor.

Abstract: A magnet assembly for measuring properties of a formation from a borehole, the magnet assembly including a first device and a second device, each device adapted for insertion into the borehole, the first device producing a first magnetic field, the second device producing a second magnetic field; wherein the second magnetic field is configurable for one of reinforcing and reducing the first magnetic field; and wherein the first device comprises a permanent magnet and the second device comprises at least one of one of a switchable magnet and switching windings.

Abstract: NMR spin echo signals are measured in a small borehole during drilling. Signals measured in a plurality of regions of investigation are combined to increase the signal strength.

Abstract: NMR spin echo signals are measured in a borehole during drilling. Signals measured in a plurality of regions of investigation with different depths of investigation in the borehole are processed to give a radial profile of formation properties, including a potential gas kick.

Abstract: NMR spin echo signals are measured in a borehole during underbalanced drilling. A magnetic field gradient in the region of examination is selected to suppress an effect of a formation fluid flow on the produced signals, the fluid flow being caused by the excess of the formation pressure over the borehole fluid pressure.

Abstract: A method for determining wettability of an earth formation zone surrounding a borehole, including the following steps: introducing paramagnetic ions into the water component of the zone; performing NMR measurements on the zone, and determining an NMR relaxation time parameter for the zone; extracting a fluid sample from the zone; performing NMR measurements on the sample, and determining the NMR relaxation time parameter for the sample; and determining wettability of the earth formation zone using the determined relaxation time parameter for the zone and the determined relaxation time parameter for the sample.

Abstract: Pulse sequences are applied to a fluid in an earth formation in a static magnetic field and NMR spin echo signals are obtained. The signals are processed to give a distribution of a relaxation time at a plurality of depths. Semblance between the distributions and a log of a formation property are used to identify depths at which portions of the distributions are similar to the formation property logs.

Abstract: A method of measuring a parameter characteristic of a rock formation in an oil well is provided for evaluating a reservoir treatment applied to a subterranean formation including the steps of injecting from a tool body suspended into a well at an injection location a known volume of fluid into the formation, performing a logging operation sensitive to a change of fluid content at several measuring points below and above the injection location; and using results of the logging operation to determine a depth profile along said well of a parameter related to fluid content.

Abstract: The grain size of a pore-scale geometric model of a clastic earth formation are adjusted so that the NMR relaxation time distribution output of the model matches a measured NMR distribution. Fluid drainage and imbibing can be simulated. Additional properties of the earth formation are predicted using the pore-scale model. The additional properties may be based on additional measurements of properties of a fluid in the formation.

Abstract: A fluid property of live crude oil removed from an earth formation is determined using nuclear magnetic resonance (NMR) measurements. A pressure cell, located on or near the earth's surface, and in which the live crude oil is disposed, is provided. An NMR tool capable of making NMR measurements on the live crude oil is provided, as is a database linking existing NMR data and the fluid property. A mapping function is created from a combination of radial basis functions and parameters of the mapping function are derived using the database. NMR data are acquired on the live crude oil using the NMR tool, and the fluid property is estimated from the acquired NMR data using the mapping function.

Abstract: NMR spin echo signals are acquired downhole. An independent component analysis is used to determine parameters of a parametric model of the T2 distribution whose output matches the measurements. The model parameters are telemetered to the surface where the properties of the formation are reconstructed. 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. 37 CFR 1.72(b).

Abstract: A technique utilizes the acquisition of data via nuclear magnetic resonance at multiple depths of investigation in a well region. The acquired data is processed to estimate variable fluid mixture densities at different radial depths. The variable fluid mixture densities and a radial response from a density tool, for example, can be used to calculate an effective fluid mixture density and used to interpret density logs. Other logs such as neutron log, induction resistivity log, and dielectric permittivity log can be combined with NMR. For these tools a corresponding effective formation property can be calculated and used to determine other formation characteristics, such as total porosity, total density, dielectric permittivity, electric resistivity, and formation characteristics derivable from these.

Abstract: Evaluating a formation by lowering a downhole tool in a wellbore penetrating the formation, injecting a fluid into the formation at an injection zone via the downhole tool, and using a formation evaluation sensor to perform a measurement at each of a plurality of locations in the wellbore each proximate the injection zone. At least two of the plurality of measurements are compared, and a formation property is determined based on the comparison.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to acquire data representing a plurality of nuclear magnetic resonance (NMR) echo trains associated with a material, such as a geological formation. Additional operations may include inverting a model of at least one of the plurality of NMR echo trains to provide an estimated distribution of transverse relaxation time constants, inverting models of selected ones of the plurality of NMR echo trains using the estimated distribution of transverse relaxation time constants to provide an estimated diffusion distribution, and inverting a model of selected ones of the plurality of NMR echo trains, using the estimated distributions of transverse relaxation time constants and diffusion, to provide an apparent and an intrinsic probability density function to identify fluid types in the material.

Abstract: A thermal management system for cooling a heat generating component of a Magnetic Resonance Imaging (MRI) apparatus includes at least one heat pipe having a portion disposed proximate the heat generating component, such as a gradient coil and/or RF coil. When heat is removed from the component, a working fluid in a relatively hotter end of the heat pipe vaporizes and travels toward a relatively colder end of the heat pipe. The colder end may be operatively coupled to a heat sink for removing the heat from the colder end and increase the overall efficiency of the system. The heat pipe may be disposed along a horizontal, a vertical direction and/or along a diagonal of the heat generating component.

Abstract: A method for inversion of multiple echo trains with different wait times uses a cutoff times for each of the echo trains for full polarization. Simultaneous inversion is carried out for T2 bins where full polarization exists. 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: Excitation-use high frequency RF generated by an RF oscillator is modulated by a modulator based on control by a pulse control unit, to give a pulse form. The generated RF pulse is then amplified by an RF amplifier, and set to a small-sized RF coil. The small-sized RF coil applies the RF pulse to a specific position of a sample placed on a sample stage, and detects echo signals of the RF pulse. The echo signal is amplified by a preamplifier, and is then sent to a phase detector. The phase detector detects the echo signal, and sent it via an A/D converter to an operation unit. The operation unit calculates T2 relaxation time constant based on intensity of the echo signal, and the water content at the predetermined position of the sample is calculated based on the calculated T2 relaxation time constant.

Abstract: A first NMR echo train is acquired with a single TE. A second NMR echo train is acquired with a first portion having the same TE and the second portion having a longer TE. When measurements are made with a low magnetic field gradient, processing the two echo trains can be used to determine gas in the formation.

Abstract: Pulse sequences are applied to a fluid in an earth formation in a static magnetic field and NMR spin echo signals are obtained. The signals are inverted to give T2 distributions at a plurality of depths. Similarities between logs of the T2 bins with resistivity and/or gamma ray logs are used to identify and subtract contributions to the NMR signal from oil. having internal gradients. From the received signals, relaxation and diffusion characteristics of the fluid are determined. The determination takes into account the internal field gradients. 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. 37 CFR 1.72(b).

Abstract: Methods and apparatus for the characterization of formation fluids are disclosed. A downhole tool disposed in a borehole penetrating a subterranean formation obtains a NMR measurement, effects a change in a characteristic of the formation fluid, and obtains another NMR measurement subsequent to the change. Alternatively, the downhole tool effects a radial gradient of a characteristic of the formation and obtains NMR measurements at two or more selected radial distances from the wellbore wall. A parameter representative of the subterranean formation or the formation fluid is further determined from the NMR measurements.

Abstract: A method for utilizing received formation data to determine one or more fluid instance such as reservoir wettability while in one of a subterranean environment or a surface environment. The method comprising: (a) obtaining at least one set of formation data wherein the set of formation data includes magnetic resonance data from two or more samples within an approximate common characteristic region in the reservoir; (b) computing from the at least one set of received formation data a first fluid instance of the one or more fluid instance using at least two mathematical variables from the group consisting of one of oil saturation, water saturation, T1, T2, diffusion coefficient, tortuosity from long time diffusion coefficient or some combination thereof; and (c) interpreting the computed first fluid instance as at least one wettability property between the fluids in a formation located in the subterranean environment and the formation.

Abstract: An apparatus for obtaining information from a subterranean environment, the apparatus includes: an atomic magnetometer configured to measure a magnetic field related to the information. An associated method for obtaining the information is also disclosed.

Abstract: A multi-station gravity and magnetic survey is carried out in a borehole. The data from the survey are processed to estimate the inclination and azimuth of the borehole. The drill collar relative permeability is estimated, and the estimated drill collar permeability is then used to remove the effects of induced magnetization of the drill collar on the magnetic measurements.

Abstract: Many reservoirs of interest include heavy oil. In such reservoirs, NMR measurements have difficulty distinguishing between heavy oil and water in the formation. An acoustic signal is used to modify the relaxation time distribution of water and heavy oil in opposite directions and thus increase the separability of the distributions.

Abstract: An apparatus for estimating a property of an earth formation having: a plurality of receiver antennas to receive nuclear magnetic resonance (NMR) signals from a plurality of angular segments in a region of investigation in response to an interaction between a static magnetic field and pulses of electromagnetic energy; and a processor configured to: receive the NMR signals from each receiver antenna, the NMR signals having first NMR signals received from each angular segment by only one receiver antenna and second NMR signals received from a same angular segment by at least two receiver antennas; associate the first NMR signals and the second NMR signals with the angular segment from which the first NMR signals and the second NMR signals were obtained; deconvolve the second NMR signals to produce deconvolved NMR signals; and estimate the property from the first NMR signals, the deconvolved NMR signals, and the associated angular segments.

Abstract: A method for determining a proportion of a hydrocarbon constituent in a mixture including at least one hydrocarbon, includes determining at least one nuclear magnetic resonance (NMR) property for at least one hydrocarbon constituent in the mixture; correlating an NMR response for the property for each hydrocarbon constituent in the mixture; and from the correlating, calculating the proportion of at least the constituent. A computer program product is also provided.

Abstract: An apparatus for estimating a nuclear magnetic resonance (NMR) property of an earth formation penetrated by a borehole, the apparatus including: a logging tool having a source of a static magnetic field configured to polarize a region of investigation in the earth formation; a transmitter antenna disposed at the logging tool and configured to transmit electromagnetic energy into the region of investigation; at least one receiver sensor disposed at the logging tool and configured to receive NMR signals from the region of investigation in response to an interaction between the static magnetic field and the transmitted electromagnetic energy; and a processor configured to: receive the NMR signals from the at least one receiver sensor; associate the NMR signals received from the at least one receiver sensor with an azimuthal direction at which the NMR signals were received; and estimate the property from the NMR signals and the associated azimuthal directions.

Abstract: Example composite materials and calibration assemblies using the same. An example calibration assembly for use in calibrating a downhole formation evaluation tool includes a first body comprising a first material and having a first geometry, a second body comprising a second material formed to receive the first body, wherein the first and second materials and the first geometry are selected so that a calibration property of the calibration assembly substantially matches a corresponding calibration property of a third material.

Abstract: A nuclear magnetic resonance well logging tool, where some embodiments comprise two, oppositely oriented magnets separated by a pole piece to guide static magnetic flux into a sensitive volume, and another pole piece serving as a core for several antennas For some embodiments, the antennas are solenoids Two of the antennas serve as transmit and receive antennas, where they are driven to generate an elliptically polarized magnetic field, and their antenna responses are combined so that the combined response is sensitive to elliptically polarized magnetic fields, but with zero gradient in the z-direction A third antenna is a receive antenna sensitive to magnetic field vectors having a sinusoidal spatial venation in the z-direction of period equal to the length of the third antenna A fourth antenna serves as a receive antenna sensitive to sinusoidal magnetic field vectors with the same spatial-frequency as the third antenna, phase shifted by 90 degrees.

Abstract: System and methods for using nuclear magnetic resonance (MR) T1 measurements for wireline, LWD and MWD applications and down-hole NMR fluid analyzers. The T1 measurements are characterized by insensitivity to motion, as the detrimental effects arising from tool motion or fluid flow are effectively reduced or eliminated. T1 measurements alone or in combination with other standard oil field measurements are shown to provide efficient data acquisition resulting in compact and robust data sets, the potential for substantially increased logging speeds, and simple methods for fluid typing, including direct and robust identification of gas.

Abstract: Many reservoirs of interest include heavy oil. In such reservoirs, partly at normal temperatures, many instruments commonly used for formation evaluation may not be able to distinguish between heavy oil and bound water in the formation. Passive or active heating is used to elevate the temperature of the fluids in the formation. At elevated temperatures, distinguishing between heavy oil and bound water is easier. Of particular interest is the increase in the resolvability of the transverse relaxation time T2 of NMR spin echo measurements. Additionally, the dielectric constant and the loss tangents of water and heavy oil show different temperature and frequency dependence.

Abstract: A method of measuring a parameter characteristic of a rock formation is provided, the method including the steps of deploying in a section of a well penetrating the rock formation a toolstring combining a tool for generating and measuring responses to a sensing field at different radial depth shells in the rock formation relative to the well and a tool to cause a flow of fluid through the different radial depth shells such that responses to the sensing field are obtained for at least two different radial depth shells and for at least two different flow conditions in said at least two different radial depth shells to determine a radial depth dependent profile of said parameter.

Abstract: The method for a hydrocarbon mixture composition determination includes the collection of at least one sample of the hydrocarbon mixture. For this sample, a nuclear magnetic resonance method is used for measuring series of hydrocarbon mixture's free inductance decrement curves within a temperature range of ?150° C. to +150°. Each free inductance decrement curve is then used to determine the solid component fraction Ps in the NMR 1H signal at a temperature, at which this value was measured. The received values are then used to plot a temperature dependence of the solid component fraction Ps in the NMR 1H signal and, based on the Ps value variation (?Psi), caused by a phase transition of the ith component due to a heating or cooling process and the content of solid and/or liquid phase components in the hydrocarbon mixture is defined by attributing the ?Psi value to the associated components of the mixture.

Abstract: The use of time-lapsed NMR diffusivity measurements in an observation well is disclosed. The observation well is cased in the zone of interest with non-magnetic and non-conductive casing that is invisible to the NMR tool. Second, because NMR measurements have a dead zone in front of the antenna depending on the spatial variation of the fixed magnet strength, for example about 2.7 inches, a distance between the casing and the formation is reduced to less than the dead zone length by drilling the observation well at small deviation of about 5° and running the casing without centralizers. Both the casing and the pad-type NMR tool will follow the low side of the borehole, ensuring the measurement volume of the NMR tool is inside the formation and beyond the annulus.

Abstract: An NMR logging tool for conducting NMR measurements in a plurality of sensitive volumes ranging up to a meter from the tool. The tool comprises a magnetic assembly using one or more permanent magnets and at least one pole piece for extending a magnet pole and shaping the magnetic field to simulate a magnetic monopole in a sensitive volume within the formation. Different embodiments of a segmented antenna enable directional NMR logging. The tool embodiments and methods of their use are suitable for wireline or LWD logging, and can be used for directional drilling.

Abstract: A method for determining fluids in a formation. The method includes obtaining open hole measurements for a borehole in the formation; identifying points in the borehole from which to obtain pressure measurements using the open hole measurements; obtaining pressure measurements at the identified points in the borehole; applying an excess pressure technique to the pressure measurements to identify a plurality of pressure compartments in the borehole; characterizing fluid in each of the plurality of compartments; and developing a drilling plan based on characterization of fluids in each of the plurality of compartments.

Abstract: A inventive flow-meter uses a measuring method which is based on the passage time of fluid molecules in a single sensor, without using any magnetic field gradient for the measurement of said fluid mean velocity. This method consists of the ultrafast irradiation of hydrogen nuclei from fluid molecules through pulses which are repeated every short time intervals, following a Carr-Purcell-Meiboom-Gill (CPMG) type sequence.

Abstract: An instrument for investigating properties of an earth formation includes a body housing a nuclear quadrupole resonance (NQR) probe, the probe having at least one coil wound around a core material and an electronics coupling, the body being adapted for insertion into a wellbore within the earth formation. A method and computer program product are provided.

Abstract: A method for estimating fluid productivity of a subsurface rock formation from within a wellbore drilled therethrough includes measuring a nuclear magnetic resonance property of the formation at a plurality of lateral depths therein. The measured nuclear magnetic resonance property is used to estimate the fluid productivity.

Abstract: A method for estimating a property of a material, the method including: acquiring data using nuclear magnetic resonance (NMR) measurements, the measurements performed by varying at least one of a magnetic field gradient (G) and an inter-echo time (TE); organizing the data according to at least one of magnetic field gradients (G) and inter-echo times (TE) used in the NMR measurements; calculating a shift of apparent transverse relaxation time (T2,app) and (longitudinal relaxation time T1)/(apparent transverse relaxation time T2,app) due to a variation of the product of G and TE; constructing a mathematical model of the NMR measurements from the shifts; and inverting the mathematical model to estimate the property.

Abstract: A method for obtaining a parameter of interest related to an earth formation, the method including: obtaining nuclear magnetic resonance (NMR) data from an NMR tool investigating the earth formation with a plurality of pulse sequences of radio frequency energy, each pulse sequence having a unique frequency, a first train of pulses having a first interecho time (TE1) and a second train of pulses having a second interecho time (TE2) different from the first interecho time; relating the NMR data to a partial porosity at points to establish an NMR response model; solving the NMR response model to calculate the partial porosity at each of the points in the earth formation; summing the partial porosity for each of the points corresponding to each depth of investigation to provide a pore volume; and associating each pore volume with the corresponding depth of investigation to provide the parameter of interest.

Abstract: A method for determining a wax appearance temperature of a fluid includes obtaining nuclear magnetic resonance (NMR) measurements of the fluid at a plurality of temperatures; deriving a NMR parameter from each of the NMR measurements; and determining the wax appearance temperature by analyzing the NMR parameter as a function of temperature. An apparatus for detecting wax appearance in a fluid includes a sample cell for holding a fluid for nuclear magnetic resonance (NMR) measurements at a plurality of temperatures; a temperature measuring device disposed proximate the sample cell; a magnet for polarizing molecules in the fluid in the sample cell; at least one radiofrequency (RF) coil for generating pulses of magnetic field and for detecting NMR signals; and circuitry for controlling and measuring the temperature of the fluid in the sample cell and for obtaining NMR measurements.

Abstract: The present invention pertains to an apparatus and method for conducting magnetic resonance measurements on fluids at high pressures and/or high temperatures. The apparatus can be used in conjunction with or as part of a downhole fluid sampling tool to perform NMR measurements on fluids withdrawn from petroleum reservoirs, or can also be used for laboratory measurements on live reservoir fluids. The apparatus can perform all of the measurements made by modern NMR logging tools, including multi-dimensional distribution functions of spin-spin (T2) and spin-lattice relaxation (T1) times and molecular diffusion coefficients. The spin densities of hydrogen and other NMR sensitive species can be computed from the distribution functions. The apparatus can also be used to predict the apparent conductivity of the fluids in the flowline from measurements of the quality factor (“Q”) of the NMR circuit. The apparent conductivity can be used to predict water cut or water salinity.

Abstract: A method for determining skin factor of a subsurface rock formation from within a wellbore drilled therethrough includes measuring a nuclear magnetic resonance property of the formation at a plurality of lateral depths therein. The measured nuclear magnetic resonance property is used to estimate the skin factor.

Abstract: Measurements are made using a plurality of measure electrodes on a pad of a logging tool. The bias and gain of the measurements prior to A/D conversion are altered using measurements made by an additional electrode that is ahead of the measure electrodes.

Abstract: The viscosity ? (in centipoise) of a heavy oil sample is determined according to an equation of the form ln ? ? g = - C ? ? 1 * ( T - c ? ? 246 ) c ? ? 47.10 + ( T - c ? ? 246 ) , where T is the temperature of the heavy oil, T2LM is the logarithmic mean of the T2 distribution of the sample obtainable from nuclear magnetic resonance (NMR) measurements, c?=1.0±0.05, c?=1.0±0.04, ?g is the glass transition temperature viscosity of the heavy oil and a function of T2LM, and C1 is a variable which is a constant for the heavy oil and is a function of T2LM. Both C1 and ?g are considered functions of certain NMR values associated with the heavy oil sample, with ?g and C1 preferably estimated by empirically fitting data to the equations lnT2LM=a?+b?ln?g and lnT2LM=a?+b?C1, where a?, b?, a? and b? are constants.

Abstract: A method for measuring nuclear magnetic properties (NMR) properties of a formation, the method including applying a magnetic field to nuclei of the formation during a polarizing interval, the magnetic field having a polarizing intensity; changing the magnetic field to a measurement intensity, the measurement intensity applied to the nuclei of the formation during a measurement interval; applying to the formation at least one radio frequency (RF) pulse train during the measurement interval; and measuring an NMR signal from the formation.

Abstract: Viscosity of heavy oil is determined in situ in a formation by making nuclear magnetic resonance (NMR) measurements in the formation, and then calculating viscosity according to an equation of the form T 2 ? LM = a + b ? ( ? T ) c , where T is the temperature of the heavy oil sample, ? is the viscosity, T2LM is the logarithmic mean of the T2 distribution spectrum of the sample, and a, b, and c are non-zero constants. Typically, constant b has a value between 5 and 7 and constant c has a value between ?0.7 and ?0.5.