A method (and corresponding system) that characterizes a porous rock sample is provided, which involves subjecting the porous rock sample to an applied experimental pressure where a first fluid that saturates the porous rock sample is displaced by a second fluid, and subsequently applying an NMR pulse sequence to the rock sample, detecting resulting NMR signals, and generating and storing NMR data representative of the detected NMR signals. The application of experimental pressure and NMR measurements can be repeated over varying applied experimental pressure to obtain NMR data associated with varying applied experimental pressure values. The NMR data can be processed using inversion to obtain a probability distribution function of capillary pressure values as a function of NMR property values. The probability distribution function of capillary pressure values as a function of NMR property values can be processed to determine at least one parameter indicative of the porous rock sample.

Methods for determining a volume of stored gas within a rock sample includes loading a rock sample into an overburden cell. A hydrocarbon gas at a gas pressure is applied to the rock sample and a confining fluid at a confining pressure is applied to the overburden cell. The confining pressure and the gas pressure are increased until a first pressure and temperature condition is met. With the rock sample maintained at the first temperature and pressure condition, a nuclear magnetic resonance spectrometer is used to scan the rock sample and measure a hydrocarbon gas volume within the rock sample. This measured hydrocarbon gas volume is then corrected using a Real Gas Index to determine the volume of stored gas within the rock sample.

Nuclear magnetic resonance (NMR) gas isotherm techniques to evaluate wettability of porous media, such as hydrocarbon reservoir rock, can include constructing a NMR gas isotherm curve for a porous media sample gas adsorption under various pressures. A hydrophobic or hydrophilic nature of the porous media sample can be determined using the NMR gas isotherm curves. A wettability of the porous media sample can be determined based on the NMR gas isotherm curve. The wettability can be determined for porous media samples with different pore sizes. In the case of reservoir rock samples, the determined wettability can be used, among other things, to model the hydrocarbon reservoir that includes such rock samples, to simulate fluid flow through such reservoirs, or to model enhanced hydrocarbon recovery from such reservoirs.

A sample chamber holder for MAS-NMR capable of operating at both low and high pressures. In one example the sample chamber holder is made up of a sample holder body defining a sample chamber therein, a connector configured to operatively statically hold an in situ rotor within the sample chamber; a coupler configured to operatively connect the sampler holder body to a magnetically coupled rotation member. The magnetically coupled rotation member is configured to engage and rotate a sealing cap from an NMR rotor in such a way so as to allow an NMR cap to be alternatively opened or sealed in-situ while the NMR rotor remains statically positioned in an NMR device.

Nuclear magnetic resonance (NMR) gas isotherm techniques to evaluate wettability of porous media, such as hydrocarbon reservoir rock, can include constructing a NMR gas isotherm curve for a porous media sample gas adsorption under various pressures. A hydrophobic or hydrophilic nature of the porous media sample can be determined using the NMR gas isotherm curves. A wettability of the porous media sample can be determined based on the NMR gas isotherm curve. The wettability can be determined for porous media samples with different pore sizes. In the case of reservoir rock samples, the determined wettability can be used, among other things, to model the hydrocarbon reservoir that includes such rock samples, to simulate fluid flow through such reservoirs, or to model enhanced hydrocarbon recovery from such reservoirs.

Nuclear magnetic resonance (NMR) gas isotherm techniques to evaluate wettability of porous media, such as hydrocarbon reservoir rock, can include constructing a NMR gas isotherm curve for a porous media sample gas adsorption under various pressures. A hydrophobic or hydrophilic nature of the porous media sample can be determined using the NMR gas isotherm curves. A wettability of the porous media sample can be determined based on the NMR gas isotherm curve. The wettability can be determined for porous media samples with different pore sizes. In the case of reservoir rock samples, the determined wettability can be used, among other things, to model the hydrocarbon reservoir that includes such rock samples, to simulate fluid flow through such reservoirs, or to model enhanced hydrocarbon recovery from such reservoirs.

The invention relates to a high-temperature and high-pressure nuclear magnetic resonance core holder. An inner cylinder body of the core holder is provided in an outer cylinder body, a nuclear magnetic resonance probe coil is provided between the outer cylinder body and the inner cylinder body, two plugging sleeves are respectively provided between both ends of the inner cylinder body and between both ends of the outer cylinder body, a sealing groove is provided at the inner side of each plugging sleeve, a sealing joint component is provided in each sealing groove of each plugging sleeve, and two ends of the nuclear magnetic resonance probe coil are respectively connected with the sealing joint component, so that the nuclear magnetic resonance probe coil can be led out. The holder disclosed by the invention is compatible with nuclear magnetic resonance, integrates injection displacement experiments and nuclear magnetic resonance measurement, and adopts a sealing solution to ensure the sealing performance of the joint of the outer cylinder body and the inner cylinder body, so as to adapt to nuclear magnetic resonance on-line measurement and analysis experiments under the condition of simulative deep basin high-temperature and high-pressure.

A method and system are described for imaging core samples associated with a subsurface region. The imaging results may be used to create or update a subsurface model and using the subsurface model and/or imaging results in hydrocarbon operations. The imaging techniques may include NMR imaging and CT imaging. Further, the imaging techniques may also include exposing the core sample to the imaging gas.

A container has a sample installation unit and an NMR circuit therein, and is connected to a bearing gas supply path and a drive gas supply path for supplying gas to the inside of that container. This container is also connected to an exhaust path that exhausts the gas from the inside of the container. The exhaust path has a pressure control valve as an adjustment mechanism for adjusting the pressure in the container.

Systems and methods for testing properties of a test sample with a tri-axial nuclear magnetic resonance include a tri-axial load frame encasing a tri-axial load cell having a tri-axial sample holder and a piston assembly. A radial space surrounds the tri-axial sample holder. The tri-axial load frame further encases at least one end cap operable to contact the tri-axial load cell, and a nuclear magnetic resonance instrument. An axial pressure line is in fluid communication with the piston assembly, a confining pressure line is in fluid communication with the radial space, and a pore pressure line in fluid communication with the test sample. The axial pressure line, the confining pressure line, and the pore pressure line are independent and separate fluid flow paths.