Abstract: To characterize an earth subterranean structure using a measurement assembly including electromagnetic (EM) receivers and one or more EM sources, measured voltage data collected by EM receivers in response to transmission by one or more EM sources is received. Based on a model, predicted EM data is computed. Inversion is iteratively performed according to a function that computes a difference between the measured voltage data and a product of a term containing the predicted EM data and a term containing distortion data that accounts at least for distortion effect by an environment of the measurement assembly. The inversion is iteratively performed to solve for parameters of the model and the distortion data.

Abstract: Characterizing a reservoir with electromagnetic imaging surveys includes normalizing measured voltage data by transmitter moment, sorting the normalized voltage data into common receiver profiles, densely resampling transmitter locations using common positions for the receiver profiles, coarsely resampling the data at discreet transmitter locations, defining a starting model for inversion, weighting the data by a factor, converting the normalized voltage data to ratios, calculating a conductivity image using a ratio inversion method, and verifying that an inversion has converged and the image is geologically reasonable. The image can then be displayed. The invention can be used for cross-well, surface-to-borehole, and borehole-to-surface measurements by which the effects of steel casing are reduced.

Abstract: A method is disclosed for building a predictive or forward model adapted for predicting the future evolution of a reservoir, comprising: integrating together a plurality of measurements thereby generating an integrated set of deep reading measurements, the integrated set of deep reading measurements being sufficiently deep to be able to probe the reservoir and being self-sufficient in order to enable the building of a reservoir model and its associated parameters; generating a reservoir model and associated parameters in response to the set of deep reading measurements; and receiving, by a reservoir simulator, the reservoir model and, responsive thereto, generating, by the reservoir simulator, the predictive or forward model.

Abstract: A method of upscaling for reservoir simulation is disclosed, comprising: inverting a set of deep reading measurements constrained by upscaled multi-well data, and, in response to the inverting step, upscaling for reservoir simulation.

Abstract: Characterizing a reservoir with electromagnetic imaging surveys includes normalizing measured voltage data by transmitter moment, sorting the normalized voltage data into common receiver profiles, densely resampling transmitter locations using common positions for the receiver profiles, coarsely resampling the data at discreet transmitter locations, defining a starting model for inversion, weighting the data by a factor, converting the normalized voltage data to ratios, calculating a conductivity image using a ratio inversion method, and verifying that an inversion has converged and the image is geologically reasonable. The image can then be displayed. The invention can be used for cross-well, surface-to-borehole, borehole-to-surface, and single-well (borehole-to-borehole) measurements by which the effects of steel casing are reduced.

Abstract: To characterize an earth subterranean structure using a measurement assembly including electromagnetic (EM) receivers and one or more EM sources, measured voltage data collected by EM receivers in response to transmission by one or more EM sources is received. Based on a model, predicted EM data is computed. Inversion is iteratively performed according to a function that computes a difference between the measured voltage data and a product of a term containing the predicted EM data and a term containing distortion data that accounts at least for distortion effect by an environment of the measurement assembly. The inversion is iteratively performed to solve for parameters of the model and the distortion data.

Abstract: To characterize an earth subterranean structure using a measurement assembly including electromagnetic (EM) receivers and one or more EM sources, measured voltage data collected by EM receivers in response to transmission by one or more EM sources is received. Based on a model, predicted EM data is computed. Inversion is iteratively performed according to a function that computes a difference between the measured voltage data and a product of a term containing the predicted EM data and a term containing distortion data that accounts at least for distortion effect by an environment of the measurement assembly. The inversion is iteratively performed to solve for parameters of the model and the distortion data.

Abstract: Characterizing a reservoir with electromagnetic imaging surveys includes normalizing measured voltage data by transmitter moment, sorting the normalized voltage data into common receiver profiles, densely resampling transmitter locations using common positions for the receiver profiles, coarsely resampling the data at discreet transmitter locations, defining a starting model for inversion, weighting the data by a factor, converting the normalized voltage data to ratios, calculating a conductivity image using a ratio inversion method, and verifying that an inversion has converged and the image is geologically reasonable. The image can then be displayed. The invention can be used for cross-well, surface-to-borehole, and borehole-to-surface measurements by which the effects of steel casing are reduced.

Abstract: A method for determining reservoir formation properties that consists of exciting the reservoir formation with an electromagnetic exciting field, measuring an electromagnetic signal produced by the electromagnetic exciting field in the reservoir formation, extracting from the measured electromagnetic signal a spectral complex resistivity as a function of frequency, fitting the spectral complex resistivity with an induced polarization model and deducing the reservoir formation properties from the fitting with the induced polarization model.

Abstract: To perform surveying of a subterranean structure, electromagnetic (EM) wavefields traveling in opposite directions are determined. A relationship is defined among the EM wavefields, where the EM wavefields include a first set of EM wavefields in a first state in which a sea surface is present, and a second set of EM wavefields in a second, different state in which the sea surface is not present. At least one EM wavefield in the relationship is determined to perform removal of sea surface-related effects.

Abstract: Techniques for estimating the fraction of water in formations being investigated use measurements of dielectric permittivity at a number of frequencies. The techniques have the advantage of minimizing or eliminating external inputs that can introduce inaccuracies.

Abstract: To perform surveying of a subterranean structure, electromagnetic (EM) wavefields traveling in opposite directions are determined. A relationship is defined among the EM wavefields, where the EM wavefields include a first set of EM wavefields in a first state in which a sea surface is present, and a second set of EM wavefields in a second, different state in which the sea surface is not present. At least one EM wavefield in the relationship is determined to perform removal of sea surface-related effects.

Abstract: Techniques for determining formation characteristics use measurements of dielectric permittivity at a number of frequencies. Determined characteristics include the vertical and horizontal formation dielectric constant and conductivity, the formation water conductivity, the water saturation, the cementation and the saturation exponents. In laminated formations these profiles can be determined for each lamina. Also, formation dielectric properties are used in determination of the rock type.

Abstract: An acoustic logging tool sleeve with a preferably discontinuous, alternating structure that is acoustically opaque in some zones, and acoustically transparent in others. The sleeve may be modular, with several stages connected together. The multiple stages provide a sleeve that may be useful with a variety of borehole logging tools to reduce or eliminate the transmission of noise to the receiving elements.

Abstract: A device and method for determining a geophysical characteristic of a borehole using at least one logging device is provided, wherein the at least one logging device includes at least one sensing device. The method includes associating the at least one sensing device with the borehole, wherein the at least one sensing device includes a sensing device measurement length. The method also includes operating the at least one sensing device to generate borehole data responsive to a borehole portion disposed essentially adjacent the sensing device measurement length, wherein the borehole data includes start time of scan, location of the at least one sensing device at start time of scan, stop time of scan and location of the at least one sensing device at stop time of scan. Furthermore, the method includes correlating the borehole data to determine the geophysical characteristic.

Abstract: A device and method for determining a geophysical characteristic of a borehole using at least one logging device is provided, wherein the at least one logging device includes at least one sensing device. The method includes associating the at least one sensing device with the borehole, wherein the at least one sensing device includes a sensing device measurement length. The method also includes operating the at least one sensing device to generate borehole data responsive to a borehole portion disposed essentially adjacent the sensing device measurement length, wherein the borehole data includes start time of scan, location of the at least one sensing device at start time of scan, stop time of scan and location of the at least one sensing device at stop time of scan. Furthermore, the method includes correlating the borehole data to determine the geophysical characteristic.

Abstract: An apparatus for use in a system that includes a network analyzer for determining a property, such as dielectric permittivity of a sample material as a function of frequency, the apparatus including: a cylindrical chamber for receiving the sample; a coaxial connector having a first relatively small diameter end coupleable with the analyzer and a second relatively large diameter end communicating with a side of the cylindrical chamber, the connector having inner and outer coaxial conductors; the inner conductor of the connector having a diameter that tapers outwardly from the first end to the second end, and the outer conductor of the connector having an inner surface whose diameter tapers outwardly from the first end to the second end. The chamber can accommodate relatively large samples, such as standard earth formation coring samples.

Abstract: Techniques for estimating the fraction of water in formations being investigated use measurements of dielectric permittivity at a number of frequencies. The techniques have the advantage of minimizing or eliminating external inputs that can introduce inaccuracies.

Abstract: Techniques for determining formation characteristics use measurements of dielectric permittivity at a number of frequencies. Determined characteristics include the vertical and horizontal formation dielectric constant and conductivity, the formation water conductivity, the water saturation, the cementation and the saturation exponents. In laminated formations these profiles can be determined for each lamina. Also, formation dielectric properties are used in determination of the rock type.

Abstract: A method and apparatus for estimating the time varying mechanical properties of a cement including propagating acoustic waves through a cement sample, measuring signals corresponding to the acoustic waves after they propagate in the sample, comparing attributes from the measured signals with corresponding attributes provided by a model accounting for at least initially estimated acoustic properties of the cement, using the differences between the measured and calculated signals to update the initially estimated acoustic properties of the material in the calculating model, using the differences between the measured and calculated signals, updating the initial acoustic properties in the model, processing N iterations of the comparison and updating either until the differences between measured and calculated signals are within a given tolerance factor or when the number i reaches a prescribed maximum and calculating the time varying mechanical properties of the cement from the final iterated acoustic properties.