Abstract: A computer-implemented method for reservoir volumetric estimation, a non-transitory computer-readable medium, and a computing system. The method may include running a molecular dynamics simulation of a fluid-rock model of a first reservoir system at a plurality of pressures. The fluid-rock model includes a fluid that is at least partially adsorbed in the first reservoir system at one or more pressures of the plurality of pressures. The method may also include calculating a plurality of isothermal density profiles of the fluid in the first reservoir system, in association with the plurality of pressures using a result of the molecular dynamics simulation. The method may further include determining a first gas accumulation of the fluid in the first reservoir system for the plurality of isothermal density profiles. The first gas accumulation is at least partially a function of a pore surface area of a sample of the first reservoir system.

Abstract: Methods for analyzing a reservoir in a formation containing hydrocarbon fluid are described. Information characterizing the formation is collected and applied to a formation simulator that is provided with a modified Darcy's law equation that accounts for at least one of gas adsorption/desorption, various modes of diffusive transport, and non-Darcy flow behavior, and the simulator is used to generate indications of the state of the reservoir and/or the state of production of hydrocarbon fluid from the reservoir. The modified Darcy's law equations are particularly useful in analyzing any type of formation containing any type of hydrocarbon fluid including shale formations containing hydrocarbon gases. According to one embodiment, a dual-porosity shape factor useful in a formation simulator is also provided.

Abstract: Methods for analyzing a reservoir in a formation containing hydrocarbon fluid are described. Information characterizing the formation is collected and applied to a formation simulator that is provided with a modified Darcy's law equation that ac counts for at least one of gas adsorption/desorption, various modes of diffusive transport, and non-Darcy flow behavior, and the simulator is used to generate indications of the state of the reservoir and/or the state of production of hydrocarbon fluid from the reservoir. The modified Darcy's law equations are particularly useful in analyzing any type of formation containing any type of hydrocarbon fluid including shale formations containing hydrocarbon gases. According to one embodiment, a dual-porosity shape factor useful in a formation simulator is also provided.

Abstract: A computer-implemented method for reservoir volumetric estimation, a non-transitory computer-readable medium, and a computing system. The method may include running a molecular dynamics simulation of a fluid-rock model of a first reservoir system at a plurality of pressures. The fluid-rock model includes a fluid that is at least partially adsorbed in the first reservoir system at one or more pressures of the plurality of pressures. The method may also include calculating a plurality of isothermal density profiles of the fluid in the first reservoir system, in association with the plurality of pressures using a result of the molecular dynamics simulation. The method may further include determining a first gas accumulation of the fluid in the first reservoir system for the plurality of isothermal density profiles. The first gas accumulation is at least partially a function of a pore surface area of a sample of the first reservoir system.