Abstract: A system and methods for predicting well performance are disclosed. The method includes obtaining first geoscience data and first performance data, obtaining second geoscience data and second performance data, and obtaining new geoscience data for a new well. The method further includes training a first neural network and determining predicted second performance data using the first neural network. The method still further includes determining a residual between the second performance data and the predicted second performance data and training a second neural network. The method still further includes determining predicted new performance data for the new well by inputting a subset of the new geoscience data into the first neural network, determining a new residual for the new well by inputting the new geoscience data into the second neural network, and updating the predicted new performance data using the new residual.

Abstract: A method for determining a matrix permeability of a subsurface formation, including the steps: acquiring a core from the subsurface formation, imposing a fluid to the core until the core is saturated with the fluid, conducting a pressure-pulse decay (PD) method on an upstream and a downstream side of the core by applying a pressure-pulse on the upstream and the downstream side of the core, and determining the matrix permeability from decays of the pressure-pulses on the upstream side and downstream side, respectively.

Abstract: A method for determining a rock property includes positioning a core sample in a core sample assembly that is enclosed in a pressurized container with a flow inlet, a flow outlet, and a pressurized fluid inlet fluidly coupled to a pressurized fluid reservoir that includes a pressurized fluid pump; sequentially performing at least three test operations on the core sample; at each of the at least three test operations, measuring an inlet pressure at the flow inlet, measuring an outlet pressure at the flow outlet, and measuring a confining pressure within the pressurized container; and determining a permeability of the core sample based at least in part on at least one of the measured inlet pressures, at least one of the measured outlet pressures, and at least one of the measured confining pressures.

Abstract: A method for determining a rock property includes positioning a core sample in a core sample assembly that is enclosed in a pressurized container with a flow inlet, a flow outlet, and a pressurized fluid inlet fluidly coupled to a pressurized fluid reservoir that includes a pressurized fluid pump; sequentially performing at least three test operations on the core sample; at each of the at least three test operations, measuring an inlet pressure at the flow inlet, measuring an outlet pressure at the flow outlet, and measuring a confining pressure within the pressurized container; and determining a permeability of the core sample based at least in part on at least one of the measured inlet pressures, at least one of the measured outlet pressures, and at least one of the measured confining pressures.

Abstract: Systems, methods, and apparatus for determining permeability of subsurface formations are provided. In one aspect, a method includes: positioning a sample of the subsurface formation in a measurement cell, fluidly connecting an inlet and an outlet of the sample to an upstream reservoir and a downstream reservoir, respectively, flowing a fluid through the sample from the upstream reservoir to the downstream reservoir, measuring changes of an upstream pressure associated with the upstream reservoir and a downstream pressure associated with the downstream reservoir in a measurement time period, and determining a matrix permeability of the subsurface formation based on measurement data before the upstream pressure and the downstream pressure merge at a merging time point.

Abstract: Methods and systems for determining fracture and matrix permeability of a subsurface formation. The system includes two upstream reservoirs and two downstream reservoirs, and a sample cell connecting to the reservoirs with valves. The sample cell has a confining pressure (CF) from a fluid. A horizontal plug sample with sleeve is placed in a measurement cell with the confining fluid (CF). A pressure gauge is connected to the small upstream reservoir, and a pressure gauge is connected to the small downstream reservoir. The results provide two sets of effective-stress-dependent permeability values (including fracture permeability and matrix permeability, respectively) for characterizing the reservoir properties.

Abstract: Methods and systems for detecting leakage in a permeability measurement system. The method includes connecting a plurality of flow lines to a first dimension of a core sample assembly, connecting one or more flow lines to a second dimension of the core sample assembly, placing the core sample assembly with the connections in a measurement cell such that the flow lines are accessible from outside of the measurement cell, connecting one or more gas sensors to one end of each of the flow lines, connecting an inlet of the measurement cell to a gas tank, setting fluid pressure inside the measurement cell to a predetermined value, and detecting a leakage in the core sample assembly by the one or more gas sensors coupled to the flow lines.

Abstract: Systems, methods, and apparatus for determining permeability of subsurface formations are provided. In one aspect, a method includes: positioning a sample of the subsurface formation in a measurement cell, fluidly connecting an inlet and an outlet of the sample to an upstream reservoir and a downstream reservoir, respectively, flowing a fluid through the sample from the upstream reservoir to the downstream reservoir, measuring changes of an upstream pressure associated with the upstream reservoir and a downstream pressure associated with the downstream reservoir in a measurement time period, and determining a matrix permeability of the subsurface formation based on measurement data before the upstream pressure and the downstream pressure merge at a merging time point.

Abstract: Methods and systems for determining fluid content in a formation sample are disclosed. The method includes disposing the formation sample with a standard sample of a known chemical composition and one or more nuclear magnetic resonance (NMR) attributes in a NMR coil or probe, and acquiring NMR signals for the formation sample and the standard sample simultaneously. The system includes a NMR probe or NMR coil, a formation sample, and a standard sample with known chemical composition and one or more nuclear magnetic resonance (NMR) attributes, wherein the formation sample and the standard sample are disposed in the NMR coil or probe, and wherein NMR signals are acquired for the formation sample and the standard sample simultaneously.

Abstract: Methods and systems method for determining core permeability of a subsurface formation. The method includes connecting an upstream reservoir to one end of a sample holder comprising a core sample of a subsurface formation, connecting a downstream reservoir to another end of the sample holder, providing a constant confining pressure within the sample holder, saturating the sample holder and the core sample with nitrogen at a saturation pressure, applying a pressure pulse to one end of the sample holder, and determining core permeability using the porosity of the mobile continuum when the pressure in the upstream reservoir, the downstream reservoir, and the mobile continuum is in equilibrium.

Abstract: Methods and systems for determining fracture and matrix permeability of a subsurface formation. The system includes two upstream reservoirs and two downstream reservoirs, and a sample cell connecting to the reservoirs with valves. The sample cell has a confining pressure (CF) from a fluid. A horizontal plug sample with sleeve is placed in a measurement cell with the confining fluid (CF). A pressure gauge is connected to the small upstream reservoir, and a pressure gauge is connected to the small downstream reservoir. The results provide two sets of effective-stress-dependent permeability values (including fracture permeability and matrix permeability, respectively) for characterizing the reservoir properties.

Abstract: Methods and systems for detecting leakage in a permeability measurement system. The method includes connecting a plurality of flow lines to a first dimension of a core sample, connecting one or more flow lines to a second dimension of the shale sample, placing the core sample with the connections in a measurement cell such that the flow lines are accessible from outside of the measurement cell, connecting one or more gas sensors to one end of each of the flow lines, connecting the outlet of the measurement cell to a gas tank, setting fluid pressure inside the measurement cell to a predetermined value, and detecting a leakage in the core sample by the one or more gas sensors coupled to the flow lines.

Abstract: Methods and systems method for determining core permeability of a subsurface formation. The method includes connecting an upstream reservoir to one end of a sample holder comprising a core sample of a subsurface formation, connecting a downstream reservoir to another end of the sample holder, providing a constant confining pressure within the sample holder, saturating the sample holder and the core sample with nitrogen at a saturation pressure, applying a pressure pulse to one end of the sample holder, and determining core permeability using the porosity of the mobile continuum when the pressure in the upstream reservoir, the downstream reservoir, and the mobile continuum is in equilibrium.

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: 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: 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.