Abstract: A method for estimating a property of a subsurface material includes conveying a carrier through a borehole penetrating the subsurface material and performing an NMR measurement in a volume of interest in the subsurface material using an NMR tool having an antenna disposed at the carrier. The method further includes receiving with the antenna a short build-up signal due to a short magnetization build-up time of the NMR measurement, an echo-train signal with short polarization time due to the NMR measurement, and an echo-train signal with long polarization time due to the NMR measurement. The method further includes inverting, simultaneously, the short build-up signal, the short-polarization-time echo-train signal, and the long-polarization-time echo-train signal using a processor to estimate the property; and transmitting a signal comprising the property to a signal receiving device.

Abstract: A method for estimating a property of a subsurface material includes conveying a carrier through a borehole penetrating the subsurface material and performing an NMR measurement in a volume of interest in the subsurface material using an NMR tool having an antenna disposed at the carrier. The method further includes receiving with the antenna a short build-up signal due to a short magnetization build-up time of the NMR measurement, an echo-train signal with short polarization time due to the NMR measurement, and an echo-train signal with long polarization time due to the NMR measurement. The method further includes inverting, simultaneously, the short build-up signal, the short-polarization-time echo-train signal, and the long-polarization-time echo-train signal using a processor to estimate the property; and transmitting a signal comprising the property to a signal receiving device.

Abstract: Method and apparatus using at least one process to reduce a data set using a data adaptive down-sampling scheme comprising a plurality of non-uniform down-sampling factors. The method may include separating the data set into a plurality of data windows, where each of the plurality of data windows corresponds to one of the plurality of non-uniform data-sampling factors; applying the down-sampling factors, and transmitting the reduced data set from a downhole location to the surface. The data set may include an NMR echo train. The apparatus may include an NMR tool configured to acquire NMR data and at least one processor configured to perform the method.

Abstract: A system and method of characterizing a property of an earth formation penetrated by a borehole are described. The method includes conveying a carrier through the borehole. The method also includes performing an NMR measurement with an NMR tool disposed at the carrier and obtaining NMR data, compressing the NMR data to generate compressed NMR data, and telemetering the compressed NMR data to a surface processor for processing. The method further includes decompressing the compressed NMR data directly to T1 or T2 domain distribution data, and determining the property of the earth formation based on the T1 or T2 domain distribution data.

Abstract: Method and apparatus using at least one process to reduce a data set using a data adaptive down-sampling scheme comprising a plurality of non-uniform down-sampling factors. The method may include separating the data set into a plurality of data windows, where each of the plurality of data windows corresponds to one of the plurality of non-uniform data-sampling factors; applying the down-sampling factors, and transmitting the reduced data set from a downhole location to the surface. The data set may include an NMR echo train. The apparatus may include an NMR tool configured to acquire NMR data and at least one processor configured to perform the method.

Abstract: Measurements of fluorescence spectra of fluid samples recovered downhole are processed to give the fluid composition. The processing may include a principal component analysis followed by a clustering method or a neutral network. Alternatively the processing may include a partial least squares regression. The latter can give the analysis of a mixture of three or more fluids.

Abstract: NMR spin echo signals are acquired downhole. Principal Component Analysis is used to represent the signals by a weighted combination of the principal components and these weights are telemetered to the surface. At the surface, the NMR spin echo signals are recovered and inverted to give formation properties.

Abstract: NMR spin echo signals are acquired downhole. Principal Component Analysis is used to represent the signals by a weighted combination of the principal components and these weights are telemetered to the surface. At the surface, the NMR spin echo signals are recovered and inverted to give formation properties. Real-time displays may be used for determining formation properties and for altering the acquisition parameters.

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: NMR spin echo signals are acquired downhole. Principal Component Analysis is used to represent the signals by a weighted combination of the principal components and these weights are telemetered to the surface. At the surface, the NMR spin echo signals are recovered and inverted to give formation properties.

Abstract: NMR spin echo signals are acquired downhole. Principal Component Analysis is used to represent the signals by a weighted combination of the principal components and these weights are telemetered to the surface. At the surface, the NMR spin echo signals are recovered and inverted to give formation properties.

Abstract: A partial least squares (PLS) regression relates spin echo signals with samples having a known parameter such as bound water (BW), clay bound water (CBW), bound volume irreducible (BVI), porosity (PHI) and effective porosity (PHE). The regression defines a predictive model that is validated and can then be applied to spin echo signals of unknown samples to directly give an estimate of the parameter of interest. The unknown samples may include earth formations in which a NMR sensor assembly is conveyed in a borehole.

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: NMR spin echo signals are acquired downhole. A partial least squares method 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 partial least squares (PLS) regression relates spin echo signals with samples having a known parameter such as bound water (BW), clay bound water (CBW), bound volume irreducible (BVI), porosity (PHI) and effective porosity (PHE). The regression defines a predictive model that is validated and can then be applied to spin echo signals of unknown samples to directly give an estimate of the parameter of interest. The unknown samples may include earth formations in which a NMR sensor assembly is conveyed in a borehole.