A vibration detection apparatus applied to a nuclear magnetic resonance while drilling instrument, including a vibration table. The vibration table is configured to horizontally clamp the nuclear magnetic resonance while drilling instrument and further includes a graduated barrel that contains a detection liquid; the graduated barrel is configured to be suspended at the upper side of the vibration table and be spaced apart from the nuclear magnetic resonance while drilling instrument; when the vibration table performs vibration, the graduated barrel keeps stationary, and the nuclear magnetic resonance while drilling instrument preforms high-pressure emission and measurement by means of the graduated barrel. Therefore, the nuclear magnetic resonance while drilling instrument can obtain the echo signal of the graduated barrel during vibration, thereby more accurately detecting the performance thereof and shortening a detection time length.

Downhole fluid volumes of a geological formation may be estimated using nuclear magnetic resonance (NMR) measurements, even in organic shale reservoirs. Multi-dimensional NMR measurements, such as two-dimensional NMR measurements and/or, in some cases, one or more well-logging measurements relating to total organic carbon may be used to estimate downhole fluid volumes of hydrocarbons such as bitumen, light hydrocarbon, kerogen, and/or water. Having identified the fluid volumes in this manner or any other suitable manner from the NMR measurements, a reservoir producibility index (RPI) may be generated. The downhole fluid volumes and/or the RPI may be output on a well log to enable an operator to make operational and strategic decisions for well production.

An apparatus (and method) for automated NMR relaxation measurements on borehole materials (e.g., drill cuttings, sidewall cores and whole cores) includes a sample cassette and a sample transfer system operating synchronized with the NMR experiment. The apparatus implements an automatic calibration, adaptive data stacking and automated measurements of the sample volume for irregular shaped samples. The measurements throughput may be increased by creating more than one excitation/detection volume during a measurement cycle. The NMR surface data may be interpreted together with other bulk sensitive measurement data (e.g. natural gamma ray spectroscopy) or/and downhole data to evaluate earth formations while drilling an oil well.

A method and system for determining a property of a substance using nuclear magnetic resonance (NMR) is described herein. The method includes applying a NMR pulse sequence to the substance. The NMR pulse sequence includes a first set of pulses and a second set of pulses. The first set of pulses and the second set of pulses encode for overlapping diffusion times. By overlapping diffusion times, the NMR pulse sequence can be used to measure a diffusion coefficient for a first diffusion time, a diffusion coefficient for a second diffusion time, and a correlation between the two overlapping diffusion times. This information, in turn, can be used to differentiate between intrinsic bulk diffusivity of the substance and the reduced diffusivity of the substance caused by restricted diffusion.

In an embodiment is provided a method of determining at least one property of a fluid that includes inducing a paramagnetic response from at least one diamagnetic species flowing through a system, the fluid including the at least one diamagnetic species; performing electron paramagnetic resonance (EPR) spectroscopy on at least a portion of the fluid to generate an EPR spectrum; and determining at least one property of the fluid based on the EPR spectrum. In another embodiment is provided a method of determining at least one property of a first fluid that includes introducing an inhibitor composition to a first fluid flowing through a system to form a second fluid; performing EPR spectroscopy on at least a portion of the second fluid to generate an EPR spectrum; and determining at least one property of the second fluid based on the EPR spectrum. Apparatus for determining fluid properties are also provided.

Wellbore cement compositions can be managed based on material characteristics determined from a cement sample. For example, a cement sample can be retrieved from a wellbore. The cement sample can be analyzed using a plurality of sensors to generate a three-dimensional mapping of particles in the cement sample. The three-dimensional mapping can represent three-dimensional spatial relationships between the particles in the cement sample. The three-dimensional mapping can be compared to baseline three-dimensional mappings in a database. The comparison of the three-dimensional mappings can be used to identify at least one material characteristic of the cement sample. Based on the at least one material characteristic of the cement sample, a cement mixture can be prepared or information related to the cement mixture can be output.

A method for analyzing unconventional rock samples using nuclear magnetic resonance (NMR), tracking fluid change in the rock sample over a time period, calculating transverse relaxation time (T.sub.2) generating fluid distribution profiles by the computer processor and based on a NMR imaging, where the fluid distribution profiles representing a movement of the fluid, and obtaining, quantification of fracture volume by the computer processor and based on the NMR imaging.

An evaluation method for hydrogen-bearing components, porosity and pore size distribution of organic-rich shale is provided, relating to a technical field of oil and gas development. The evaluation method includes steps of: according to differences among NMR (nuclear magnetic resonance) T.sub.1-T.sub.2 maps of kerogen, oil-adsorbed kerogen, clay minerals of different water-containing conditions, shale, dry shale sample, oil-saturated shale sample and water-saturated shale sample, establishing a classification scheme for each hydrogen-bearing component and a quantitative characterization method for fluid components of the organic-rich shale; with a T.sub.2 distribution of the organic-rich shale after being saturated with oil as a target and a T.sub.2 distribution of the dry shale sample as a basement, subtracting the basement, and obtaining a T.sub.2 distribution of oil in pores; and based on the T.sub.2 distribution of oil in the pores, evaluating the porosity and the pore size distribution of the organic-rich shale. Compared with a conventional method, the present invention shows relatively high innovativeness and credibility, which is beneficial to perfecting analysis of NMR in shale petrophysical measurement.

A method and system for interspersing different wait times in trainlet and partial recovery sequences is provided. The method includes introducing a nuclear magnetic resonance (NMR) tool into a wellbore penetrating a subterranean formation. The method also includes applying an NMR pulse sequence to the subterranean formation using the NMR tool, in which the NMR pulse sequence includes at least two different wait times interspersed between successive sequences of radio frequency (RF) pulses. The method also includes measuring one or more echo signals corresponding to a substance in the subterranean formation based on the applied NMR pulse sequence. The method also includes determining a distribution of a characteristic of the substance based on the measured one or more echo signals.

Nuclear magnetic resonance (NMR) relaxation and/or diffusion measurements are used to deduce fluid compositional information such as a chain-length distribution, which may then be used to predict the true boiling points (TBP) of a sample of a complex hydrocarbon fluid mixture, such as a crude oil. The NMR measurements may be considered a fast and portable proxy measurement in estimating fluid TBP distributions in lieu of distillation methods, or the simulated distillation by gas chromatography.