Abstract: Nuclear magnetic resonance (NMR) well logs are obtained from a well in the reservoir measures of the total fluid, including both water and hydrocarbon, in the shale of the reservoir. NMR measurement at the surface of shale subsurface samples obtained in the form of drill cuttings or core samples from the same well provide measures of total water content of the shale. At the surface, pressure on the subsurface sample becomes that of atmospheric pressure, and hydrocarbon gas contained in the shale cuttings bleeds off. The remaining fluid within the shale cuttings is then only water, which can be measured using NMR techniques. Compensation for the effect of drilling fluids (drilling mud) on the NMR measures from the fluid cuttings is also performed. The hydrocarbon gas content of the formation shale can be determined from the difference between formation NMR well log readings and NMR measurements from subsurface sample.

Abstract: Techniques for determining geologic formation permeability include determining particular permeability values from an NMR log permeability data and particular permeability values of the core permeability measurements; determining a selected NMR permeability transform that includes inputs including the determined particular permeability values; minimizing a cost function to optimize the selected NMR permeability transform; calculating new permeability values for the wellbore between the terranean surface and a true vertical depth of the wellbore with the optimized NMR permeability transform; comparing the calculated new permeability values at particular depths between the terranean surface and the true vertical depth that match depths of the core permeability measurements; based on the comparison meeting a particular threshold, generating a user interface that renders one or more graphical representations of the optimized NMR permeability transform and the calculated new permeability values; and transmitting d

Abstract: The present invention relates to methods for analyzing and modeling natural gas flow in subterranean shale reservoirs. In preferred embodiments, methodologies and techniques for determining and modeling natural gas flow in shale formations using methodologies and techniques capable of determining natural gas properties related to dual-continuum flow, permeability and pressure within a subterranean shale reservoir. In some embodiments, the natural gas properties are determined by subjecting a subterranean shale reservoir sample to pulse-decay analysis. In certain embodiments, the methodologies and techniques described herein may be used in various reservoirs exhibiting macroporosity and/or microporosity, such as fractured reservoirs and carbonate reservoirs composed of reservoir fluids.

Abstract: Methods and systems for determining permeability, as a function of pore pressure, and porosity of a subsurface formation. The method includes positioning a sample in a sample assembly comprising of a gas and a pressure gauge, inside a pressure vessel comprising gas or liquid and a pressure gauge, measuring a first gas pressure, pi, of the sample inside the pressure vessel, applying a second gas pressure, po, to the pressure vessel, the second gas pressure being greater than the first gas pressure, measuring a third gas pressure, p, at time, t, at location, x, from the inlet of sample inside the pressure vessel, determining a total gas mass per unit volume of the subsurface formation, m, and determining the permeability, k, of the subsurface formation as a function of pore pressure based at least in part on the first gas pressure, the second pressure, the third gas pressure, and the gas density, with a single test run.

Abstract: Nuclear magnetic resonance (NMR) well logs are obtained from a well in the reservoir measures of the total fluid, including both water and hydrocarbon, in the shale of the reservoir. NMR measurement at the surface of shale subsurface samples obtained in from drill cuttings or core samples of the same well provide measures of total water content of the shale. At the surface, pressure on the subsurface sample becomes that of atmospheric pressure, and hydrocarbon gas contained in the shale cuttings bleeds off. The remaining fluid within the shale cuttings is then only water, which can be measured using NMR techniques. Compensation for the effect of drilling fluids (drilling mud) on the NMR measures from the fluid cuttings is also performed. The hydrocarbon gas content of the formation shale can be determined from the difference between formation NMR well log readings and NMR measurements from subsurface sample.

Abstract: The present disclosure describes methods and systems for fracturing geological formations in a hydrocarbon reservoir. One method includes forming a borehole in a hydrocarbon reservoir from a surface of the hydrocarbon reservoir extending downward into the hydrocarbon reservoir; transmitting an electromagnetic (EM) wave through the borehole: directing at least a portion of the EM wave to rocks at a location below the surface in the hydrocarbon reservoir; and fracturing the rocks at the location below the surface in the hydrocarbon reservoir by irradiating the rocks around the borehole using at least the portion of the EM wave, wherein irradiating the rocks elevates pore-water pressure in the rocks causing fracturing of the rocks.

Abstract: Systems and methods for analyzing and modeling natural gas flow in subterranean shale reservoirs. In some embodiments, methodologies and techniques for determining and modeling natural gas flow in shale formations using methodologies and techniques capable of determining natural gas properties related to dual-continuum flow, permeability, and pressure within a subterranean shale reservoir. In some embodiments, the natural gas properties are determined by subjecting a subterranean shale reservoir sample to pulse-decay analysis. In certain embodiments, the methodologies and techniques described may be used in various reservoirs exhibiting macroporosity and microporosity, such as fractured reservoirs and carbonate reservoirs composed of reservoir fluids.

Abstract: Methods and systems for detecting impact of induced micro-fractures in a subsurface formation are disclosed. The method includes determining an unloading effective stress (?ul) in a formation sample taken from a wellbore drilled into the subsurface formation, determining a fracture closure stress (?cl) of the formation sample, determining that the unloading effective stress (?ul) is greater than or equal to the fracture closure stress (?ul), and in response to determining that unloading effective stress (?ul) is greater than or equal to the fracture closure stress (?ul), operating the well system to inhibit impact of micro-fractures in the wellbore.

Abstract: Systems and methods for determining shear failure of a rock formation are disclosed. The method includes receiving, by a processor, a plurality of parameters related to physical properties of the rock formation, applying the plurality of parameters to a predetermined failure criterion, and determining shear failure of the rock formation based on the failure criterion. In some embodiments the failure criterion is a modified Hoek-Brown failure criterion that takes into consideration an intermediate principal stress, and the difference between normal stresses and an average confining stress.

Abstract: The present disclosure describes methods and systems for fracturing geological formations in a hydrocarbon reservoir. One method includes forming a borehole in a hydrocarbon reservoir from a surface of the hydrocarbon reservoir extending downward into the hydrocarbon reservoir; transmitting an electromagnetic (EM) wave through the borehole: directing at least a portion of the EM wave to rocks at a location below the surface in the hydrocarbon reservoir; and fracturing the rocks at the location below the surface in the hydrocarbon reservoir by irradiating the rocks around the borehole using at least the portion of the EM wave, wherein irradiating the rocks elevates pore-water pressure in the rocks causing fracturing of the rocks.

Abstract: A subterranean zone can be treated by introducing an acid-generating material and a proppant to the subterranean zone. Fractures are created in the subterranean zone using the acid-generating material. The proppant is positioned within the created fractures to keep the fractures open.

Abstract: Methods and systems for determining permeability, as a function of pore pressure, and porosity of a subsurface formation. The method includes positioning a sample in a sample assembly comprising of a gas and a pressure gauge, inside a pressure vessel comprising gas or liquid and a pressure gauge, measuring a first gas pressure, pi, of the sample inside the pressure vessel, applying a second gas pressure, po, to the pressure vessel, the second gas pressure being greater than the first gas pressure, measuring a third gas pressure, p, at time, t, at location, x, from the inlet of sample inside the pressure vessel, determining a total gas mass per unit volume of the subsurface formation, m, and determining the permeability, k, of the subsurface formation as a function of pore pressure based at least in part on the first gas pressure, the second pressure, the third gas pressure, and the gas density, with a single test run.

Abstract: The disclosure relates to methods for determining imbibition of hydraulic fracturing fluids into hydrocarbon-bearing formations. More specifically, the disclosure relates to laboratory methods for determining certain unconventional flow parameters to measure the imbibition over time of hydraulic fracturing fluids into a low-permeability hydrocarbon-bearing rock formation.

Abstract: Methods and systems for removing near wellbore damage in a hydrocarbon reservoir are described. In one example implementation, an antenna is positioned inside a wellbore in a location corresponding to a formation where near wellbore damage occurs. The wellbore extends from a surface of a hydrocarbon reservoir downward into the subterranean structure of the hydrocarbon reservoir. An electromagnetic (EM) wave is transmitted to the antenna. A portion of the EM wave is irradiated at the formation. The portion of the EM wave removes the near wellbore damage at the formation.

Abstract: Methods and systems disclosed here include conducting two pressure-dependent permeability tests having the same range of effective stress but two different values of pore pressure. For the test with the higher pore pressure, the permeability is only impacted by the mechanical deformation of the rock, while for the one with lower pore pressure the permeability is impacted by both mechanical deformation of the rock and the Knudsen diffusion. By using the same range of effective stress, the contribution from the mechanical deformation of the rock should be the same. Therefore, by subtracting the permeability with higher pore pressure from the one with lower pore pressure, the impact of Knudsen diffusion and the mechanical deformation of the rock can be determined.

Abstract: Methods and systems for determining permeability, as a function of pore pressure, and porosity of a subsurface formation. The method includes positioning a sample in a sample assembly comprising of a gas and a pressure gauge, inside a pressure vessel comprising gas or liquid and a pressure gauge, measuring a first gas pressure, pi, of the sample inside the pressure vessel, applying a second gas pressure, po, to the pressure vessel, the second gas pressure being greater than the first gas pressure, measuring a third gas pressure, p, at time, t, at location, x, from the inlet of sample inside the pressure vessel, determining a total gas mass per unit volume of the subsurface formation, m, and determining the permeability, k, of the subsurface formation as a function of pore pressure based at least in part on the first gas pressure, the second pressure, the third gas pressure, and the gas density, with a single test run.

Abstract: Methods and systems for determining permeability, as a function of pore pressure, and porosity of a subsurface formation. The method includes positioning a sample in a sample assembly comprising of a gas and a pressure gauge, inside a pressure vessel comprising gas or liquid and a pressure gauge, measuring a first gas pressure, pi, of the sample inside the pressure vessel, applying a second gas pressure, po, to the pressure vessel, the second gas pressure being greater than the first gas pressure, measuring a third gas pressure, p, at time, t, at location, x, from the inlet of sample inside the pressure vessel, determining a total gas mass per unit volume of the subsurface formation, m, and determining the permeability, k, of the subsurface formation as a function of pore pressure based at least in part on the first gas pressure, the second pressure, the third gas pressure, and the gas density, with a single test run.

Abstract: Methods and systems disclosed here include conducting two pressure-dependent permeability tests having the same range of effective stress but two different values of pore pressure. For the test with the higher pore pressure, the permeability is only impacted by the mechanical deformation of the rock, while for the one with lower pore pressure the permeability is impacted by both mechanical deformation of the rock and the Knudsen diffusion. By using the same range of effective stress, the contribution from the mechanical deformation of the rock should be the same. Therefore, by subtracting the permeability with higher pore pressure from the one with lower pore pressure, the impact of Knudsen diffusion and the mechanical deformation of the rock can be determined.

Abstract: The disclosure relates to methods for determining imbibition of hydraulic fracturing fluids into hydrocarbon-bearing formations. More specifically, the disclosure relates to laboratory methods for determining certain unconventional flow parameters to measure the imbibition over time of hydraulic fracturing fluids into a low-permeability hydrocarbon-bearing rock formation.

Abstract: The present disclosure describes methods and systems for fracturing geological formations in a hydrocarbon reservoir. One method includes forming a borehole in a hydrocarbon reservoir from a surface of the hydrocarbon reservoir extending downward into the hydrocarbon reservoir; transmitting an electromagnetic (EM) wave through the borehole: directing at least a portion of the EM wave to rocks at a location below the surface in the hydrocarbon reservoir; and fracturing the rocks at the location below the surface in the hydrocarbon reservoir by irradiating the rocks around the borehole using at least the portion of the EM wave, wherein irradiating the rocks elevates pore-water pressure in the rocks causing fracturing of the rocks.