Abstract:
To measure the phase behavior of a fluid in a porous medium such as a tight gas shale, one illustrative method involves: (a) loading the fluid into a sample cell containing the porous medium; (b) setting a pressure and a temperature for the fluid in the sample cell; (c) applying an RF pulse sequence to the fluid in the sample cell to acquire an NMR signal; (d) deriving from the NMR signal an NMR parameter distribution that depends on the pressure and the temperature; (e) determining whether a fluid phase is present based on the NMR parameter distribution; (f) repeating operations (c) through (f) to determine the presence or absence of the fluid phase at multiple points along a pressure-temperature path that crosses a phase boundary; and (g) providing an estimated location of the phase boundary based on the presence or absence of the fluid phase at said points.
Abstract:
Exemplary implementations may: obtain subsurface relaxation time data specifying subsurface relaxation time values corresponding to a well in the subsurface volume of interest; generating a subsurface relaxation time distribution using the subsurface relaxation time data; generating a subsurface porosity distribution using the subsurface relaxation time distribution; generating a representation of the subsurface porosity distribution in the subsurface volume of interest using visual effects to depict at least one of the one or more subsurface relaxation time values; and display the representation.
Abstract:
A sensor and a method are disclosed for analyzing fluid and/or rock samples from a subsurface formation. Embodiments of the sensor and method utilize an array of magnets arranged in a specific way. The array and its arrangement may allow for NMR analysis of multiple samples or analysis of fluid samples which were not possible with existing technology. Further details and advantages of various embodiments of the method are described in more detail herein.
Abstract:
A device including a plurality of motors is disclosed. The device includes a body comprising a plurality of magnet arrays. Each magnet array comprises a plurality of magnets which define a polygon and the plurality of magnets are arranged in a semi-Halbach configuration. The polygons of the plurality of magnet arrays form a tessellating pattern in which the magnet arrays each share at least one magnet with another one of the magnet arrays. Each magnet is configured to be rotatable relative to the body, or in the case of coils as magnets, the input of each coil can be manipulated to replicate the same or similar effect. The device further comprises a plurality of rotors, wherein each magnet array is configured to receive a rotor rotatable relative to the body.
Abstract:
An NMR sensor and method is disclosed for analyzing a core sample from a subsurface formation. Embodiments of the method utilize two or more magnets disposed proximate to each other. The configuration of the magnets allows for increased detection frequency, and creates a strong field with much finer resolution than existing designs. In addition, embodiments of the sensor may be used at the well site due to its small size and simple hardware. Further details and advantages of various embodiments of the method are described in more detail herein.
Abstract:
A disclosed method for characterizing gas adsorption on a rock sample includes: measuring a nuclear magnetic resonance (NMR) response of the rock as a function of surrounding gas pressure along an isotherm; transforming the NMR response to obtain a Langmuir pressure distribution of gas adsorption on the rock sample; and displaying the Langmuir pressure distribution. The Langmuir pressure distribution may be shown in one dimension (e.g., contribution to signal response versus Langmuir pressure), or may be combined with additional pressure-dependencies such as spin-lattice relaxation time (T1), spin-spin relaxation time (T2), and chemical shift (δ) to form a multi-dimensional distribution. The method can further include: identifying peaks in the Langmuir pressure distribution; and associating a gas storage mechanism and capacity with each peak. It may still further include: exposing the rock sample to a treatment fluid to obtain an altered sample; repeating said measuring and transforming operations with the altered sample; and comparing the Langmuir pressure distributions to determine effects of the treatment.
Abstract:
An NMR sensor and method is disclosed for analyzing a core sample from a subsurface formation. Embodiments of the method utilize two or more magnets disposed proximate to each other. The configuration of the magnets allows for increased detection frequency, and creates a strong field with much finer resolution than existing designs. In addition, embodiments of the sensor may be used at the well site due to its small size and simple hardware. Further details and advantages of various embodiments of the method are described in more detail herein.
Abstract:
A sensor and a method are disclosed for analyzing fluid and/or rock samples from a subsurface formation. Embodiments of the sensor and method utilize an array of magnets arranged in a specific way. The array and its arrangement may allow for NMR analysis of multiple samples or analysis of fluid samples which were not possible with existing technology. Further details and advantages of various embodiments of the method are described in more detail herein.