A method includes generating a temperature-corrected nuclear magnetic resonance (NMR) measurement-derived value corresponding to a target temperature using a correlation model that is based on a difference between the target temperature and a sample temperature. The method also includes determining a formation property based on the temperature-corrected NMR measurement-derived value corresponding to the target temperature.

A method of characterizing chemical and/or morphological features of a material, comprising acquiring energy relaxation data from 1H low field nuclear magnetic resonance (.sup.1H LF-NMR) measurements of said material, converting the relaxation signals into a multidimensional distribution of longitudinal and transverse relaxation times by solving an inverse problem under both L.sub.1 and L.sub.2 regularizations and further imposing a non-negativity constraint, and identifying one or more characteristics of said material with the aid of said multidimensional T1-T2 distribution. The method is useful, inter alia, in monitoring chemical processes, screening of additives and quality control.

A method determines a calibration specification specifying a functional correlation between an NMR measurement variable, determined using an NMR measuring device, for a material to be analyzed and a humidity contained in the material to be analyzed. The method includes provision of a relaxation curve of the material having a known humidity; determination of a relaxation time distribution from the relaxation curve provided; and determination of an approximate relaxation time distribution relative to at least one other humidity. The at least one other humidity is less than the known humidity. The method further includes reconstruction of another relaxation curve from the approximate relaxation time distribution; determination of an expected NMR measurement variable from the reconstructed other relaxation curve for the at least one other humidity; and determination of the calibration specification as a function of the humidity contained in the material, in accordance with the determinable NMR measurement variable.

Methods and systems for determining fluid content in a formation sample are disclosed. The method includes disposing the formation sample with a standard sample of a known chemical composition and one or more nuclear magnetic resonance (NMR) attributes in a NMR coil or probe, and acquiring NMR signals for the formation sample and the standard sample simultaneously. The system includes a NMR probe or NMR coil, a formation sample, and a standard sample with known chemical composition and one or more nuclear magnetic resonance (NMR) attributes, wherein the formation sample and the standard sample are disposed in the NMR coil or probe, and wherein NMR signals are acquired for the formation sample and the standard sample simultaneously.

A process for producing liquid transportation fuels in a petroleum refinery while avoiding the usage of crude oil feed stock that characterized by a fouling thermal resistance having the potential to foul refinery processes and equipment. Spectral data selected from NIR, NMR or both is obtained and converted to wavelets coefficients data. A genetic algorithm (or support vector machines) is then trained to recognize subtle features in the wavelet coefficients data to allow classification of crude samples into one of two groups based on fouling potential. Rapid classification of a potential crude oil feed stock according to its fouling potential prevents the utilization of feed stocks characterized by increased fouling potential in a petroleum refinery to produce liquid transportation fuels.

A method of estimating properties of a resource bearing formation includes receiving, by a processor, a measured echo train generated by a nuclear magnetic resonance (NMR) measurement device deployed in a region of interest, and a measured noise of the measured echo train, and calculating a T.sub.2 distribution subject to a nonlinear equality constraint, the nonlinear equality constraint dependent on the measured noise and a fitting error between the measured echo train and a modeled echo train. Calculating the T.sub.2 distribution includes estimating a solution for the T.sub.2 distribution that is closest to satisfying the nonlinear equality constraint.

Disclosed is a system and method for sorting copper-bearing ore to select portions having a target copper content. The system includes an analysis and selection station including first magnetic resonance analyzer measuring the copper content of input ore and a controlled diverter to divert portions of the input ore to a collection path when the copper content meets or exceeds a predetermined cut-off value. The predetermined cut-off is adjusted by a controller in response to the first magnetic resonance analyzer. A second magnetic resonance analyzer measures the copper content of the ore in a product path. That measurement is fed back to the controller to fine tune the adjusted cut-off value above, up or down, to optimize the yield of ore having the targeted copper content. The system may include a station for sizing the input ore, a station for sizing the output ore, and a station for sizing waste produced by the system.

A method for determining the porosity of a core sample can include: submerging a core sample in a NMR saturation fluid, wherein the core sample has a permeability of 10 mD or less; exposing the fluid to a vacuum while the core sample is submerged the NMR saturation fluid for a sufficient period of time to saturate the core sample; removing the vacuum while maintaining the core sample submerged the NMR saturation fluid; taking a NMR measurement of fluids in the core sample; and determining a porosity of the core sample based on a correlation between the NMR measurement and a NMR signal to fluid volume calibration.

The present invention relates to a method of measuring the diffusion coefficient of water in a porous medium. The coefficient is measured using a nuclear magnetic resonance (NMR) technique (2, 3, 4) and the sample (1) has the shape of a hollow cylinder.

The present disclosure is directed to a method of determining wettability characteristics of a sub-surface formation within a wellbore utilizing nuclear magnetic resonance (NMR) and bulk fluid measurements at various stages of fluid saturation at that wellbore location. In another aspect, the pumping pressure is incrementally changed within the wellbore, measuring injection fluid and hydrocarbon saturation data values between the incremental pump pressure changes. In another aspect, a measuring and sampling tool is disclosed to execute the method and produce wettability characteristics. In another aspect, a system is disclosed that can operate NMR devices, bulk fluid equipment, pump systems, and other devices to collect data and to determine wettability characteristics on the collected data.