Noise in drilling operation measurements can be eliminated or reduced using machine learning. For example, a system described herein can receive one or more measured signals in a logging-while-drilling process for drilling a wellbore. The system can determine a coupling factor for noise in the one or more measured signals. The system can generate a corrected signal by removing the noise multiplied by the coupling factor from the one or more measured signals. The system can output the corrected signal for use in drilling operations in the wellbore.

Noise in drilling operation measurements can be eliminated or reduced using machine learning. For example, a system described herein can receive one or more measured signals in a logging-while-drilling process for drilling a wellbore. The system can determine a coupling factor for noise in the one or more measured signals. The system can generate a corrected signal by removing the noise multiplied by the coupling factor from the one or more measured signals. The system can output the corrected signal for use in drilling operations in the wellbore.

A device and method is described to parallelize a pressure-volume-temperature (“PVT”) analysis using gas chromatography and mass spectrometry techniques such that a portion of the pressure, temperature and volume analysis is performed separately from others. The resulting PVT data is then recombined statistically for a complete PVT analysis. The device may also obtain compositional data of the fluid to perform an equation of state analysis or reservoir simulations.

A device and method is described to parallelize a pressure-volume-temperature (“PVT”) analysis using gas chromatography and mass spectrometry techniques such that a portion of the pressure, temperature and volume analysis is performed separately from others. The resulting PVT data is then recombined statistically for a complete PVT analysis. The device may also obtain compositional data of the fluid to perform an equation of state analysis or reservoir simulations.

A method for calculating a magnetic influence factor (MIF) between an atom and a resonant atom of a molecule of a material includes determining a current magnetic field strength at a test location above a quantity of material buried at the test location, transmitting a test signal from an antenna at the test location, the test signal comprising a test fundamental frequency, and detecting, at the test location, a reflected wave comprising the test fundamental frequency on the antenna. The method includes varying the test fundamental frequency while retransmitting the test signal and detecting a reflected wave until reflected waves of various test frequencies are detected and identifying from the detected reflected waves a resonant frequency corresponding to a maximum magnitude of the detected reflected waves. The material includes molecules with a resonant atom and at least one atom different than the resonant atom.

A method for calculating a magnetic influence factor (MIF) between an atom and a resonant atom of a molecule of a material includes determining a current magnetic field strength at a test location above a quantity of material buried at the test location, transmitting a test signal from an antenna at the test location, the test signal comprising a test fundamental frequency, and detecting, at the test location, a reflected wave comprising the test fundamental frequency on the antenna. The method includes varying the test fundamental frequency while retransmitting the test signal and detecting a reflected wave until reflected waves of various test frequencies are detected and identifying from the detected reflected waves a resonant frequency corresponding to a maximum magnitude of the detected reflected waves. The material includes molecules with a resonant atom and at least one atom different than the resonant atom.

A method for magnetic resonance imaging uses an electromagnet [304], which may have open geometry, to generate a spatially nonuniform magnetic field within an imaging region [306]. The current through the electromagnet is controlled to repeatedly cycle the nonuniform magnetic field between a high strength for polarizing spins and a low strength for spatial encoding and readout. Using RF coils [308], excitation pulses are generated at a frequency that selects a non-planar isofield slice for imaging. The RF coils are also used to generate refocusing pulses for imaging and to generate spatial encoding pulses, which may be nonlinear. Magnetic resonance signals originating from the selected non-planar isofield slice of the nonuniform magnetic field in the imaging region [306] are detected using the RF coils [308] in parallel receive mode. MRI images are reconstructed from the parallel received magnetic resonance signals, e.g., using algebraic reconstruction.

A method for determining the pore size distribution in a reservoir, including the steps: drilling a core sample out of the reservoir, determining a porosity distribution along the core sample, obtaining T.sub.2-distributions at different saturation levels of the core sample with formation brine, performing time domain subtraction on the T.sub.2-distributions to obtain T.sub.2-distributions at all saturation levels, determining the pore throat size distribution along the core sample, determining first porosities from the T.sub.2-distributions that correspond to second porosities of the pore throat size distribution for each saturation level, determining T.sub.2-distributions at the first porosities from the T.sub.2-distributions, determining pore throat sizes at the second porosities from the pore throat size distributions, plotting the pore throat sizes as function of the relaxation times T.sub.2 to obtain the surface relaxation, and determining the pore size distribution of the reservoir.

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.

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.