The Experts below are selected from a list of 45 Experts worldwide ranked by ideXlab platform

Herbert F Wang - One of the best experts on this subject based on the ideXlab platform.

  • elastic wave propagation and attenuation in a double porosity dual permeability medium
    International Journal of Rock Mechanics and Mining Sciences, 2000
    Co-Authors: James G Berryman, Herbert F Wang
    Abstract:

    Abstract To account for large-volume low-permeability storage porosity and low-volume high-permeability fracture/crack porosity in oil and gas reservoirs, phenomenological equations for the poroelastic behavior of a double porosity medium have been formulated and the coefficients in these linear equations identified. This generalization from a single porosity model increases the number of independent inertial coefficients from three to six, the number of independent drag coefficients from three to six, and the number of independent stress–strain coefficients from three to six for an isotropic applied stress and assumed isotropy of the medium. The analysis leading to physical interpretations of the inertial and drag coefficients is relatively straightforward, whereas that for the stress–strain coefficients is more tedious. In a quasistatic analysis, the physical interpretations are based upon considerations of extremes in both spatial and temporal scales. The limit of very short times is the one most pertinent for wave propagation, and in this case both matrix porosity and fractures are expected to behave in an undrained fashion, although our analysis makes no assumptions in this regard. For the very long times more relevant to reservoir drawdown, the double porosity medium behaves as an equivalent single porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the Total Compressibility) may be determined by appropriate field tests. At the mesoscopic scale, pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the Compressibility can be measured for a single fracture. We show explicitly how to generalize the quasistatic results to incorporate wave propagation effects and how effects that are usually attributed to squirt flow under partially saturated conditions can be explained alternatively in terms of the double-porosity model. The result is therefore a theory that generalizes, but is completely consistent with, Biot’s theory of poroelasticity and is valid for analysis of elastic wave data from highly fractured reservoirs.

  • elastic wave propagation and attenuation in a double porosity dual permeability medium
    Nevill Cook Memorial Conference Berkeley CA (US) 10 16 1998--10 17 1998, 1998
    Co-Authors: James G Berryman, Herbert F Wang
    Abstract:

    To account for large-volume low-permeability storage porosity and low-volume high-permeability fracture/crack porosity in oil and gas reservoirs, phenomenological equations for the poroelastic behavior of a double porosity medium have been formulated and the coefficients in these linear equations identified. The generalization from a single porosity model increases the number of independent inertial coefficients from three to six, the number of independent drag coefficients from three to six, and the number of independent stress-strain coefficients from three to six for an isotropic applied stress and assumed isotropy of the medium. The analysis leading to physical interpretations of the inertial and drag coefficients is relatively straightforward, whereas that for the stress-strain coefficients is more tedious. In a quasistatic analysis, the physical interpretations are based upon considerations of extremes in both spatial and temporal scales. The limit of very short times is the one most relevant for wave propagation, and in this case both matrix porosity and fractures are expected to behave in an undrained fashion, although our analysis makes no assumptions in this regard. For the very long times more relevant for reservoir drawdown, the double porosity medium behaves as an equivalent single porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the Total Compressibility) may be determined by appropriate field tests. At the mesoscopic scale pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the Compressibility can be measured for a single fracture. We show explicitly how to generalize the quasistatic results to incorporate wave propagation effects and how effects that are usually attributed to squirt flow under partially saturated conditions can be explained alternatively in terms of the double-porosity model. The result is therefore a theory that generalizes, but is completely consistent with, Biot's theory of poroelasticity and is valid for analysis of elastic wave data from highly fractur

  • the elastic coefficients of double porosity models for fluid transport in jointed rock
    Journal of Geophysical Research, 1995
    Co-Authors: James G Berryman, Herbert F Wang
    Abstract:

    Phenomenological equations (with coefficients to be determined by specified experiments) for the poroelastic behavior of a dual porosity medium are formulated, and the coefficients in these linear equations are identified. The generalization from the single-porosity case increases the number of independent coefficients for volume deformation from three to six for an isotropic applied stress. The physical interpretations are based upon considerations of different temporal and spatial scales. For very short times, both matrix and fractures behave in an undrained fashion. For very long times, the double-porosity medium behaves like an equivalent single-porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the Total Compressibility) may be determined by appropriate field tests. At an intermediate or mesoscopic scale, pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the Compressibility can be measured for a single fracture. All six coefficients are determined from the three poroelastic matrix coefficients and the fracture Compressibility from the single assumption that the solid grain modulus of the composite is approximately the same as that of the matrix for a small fracture porosity. Under this assumption, the Total Compressibility and three-dimensional storage coefficient of the composite are the volume averages of the matrix and fracture contributions.

James G Berryman - One of the best experts on this subject based on the ideXlab platform.

  • elastic wave propagation and attenuation in a double porosity dual permeability medium
    International Journal of Rock Mechanics and Mining Sciences, 2000
    Co-Authors: James G Berryman, Herbert F Wang
    Abstract:

    Abstract To account for large-volume low-permeability storage porosity and low-volume high-permeability fracture/crack porosity in oil and gas reservoirs, phenomenological equations for the poroelastic behavior of a double porosity medium have been formulated and the coefficients in these linear equations identified. This generalization from a single porosity model increases the number of independent inertial coefficients from three to six, the number of independent drag coefficients from three to six, and the number of independent stress–strain coefficients from three to six for an isotropic applied stress and assumed isotropy of the medium. The analysis leading to physical interpretations of the inertial and drag coefficients is relatively straightforward, whereas that for the stress–strain coefficients is more tedious. In a quasistatic analysis, the physical interpretations are based upon considerations of extremes in both spatial and temporal scales. The limit of very short times is the one most pertinent for wave propagation, and in this case both matrix porosity and fractures are expected to behave in an undrained fashion, although our analysis makes no assumptions in this regard. For the very long times more relevant to reservoir drawdown, the double porosity medium behaves as an equivalent single porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the Total Compressibility) may be determined by appropriate field tests. At the mesoscopic scale, pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the Compressibility can be measured for a single fracture. We show explicitly how to generalize the quasistatic results to incorporate wave propagation effects and how effects that are usually attributed to squirt flow under partially saturated conditions can be explained alternatively in terms of the double-porosity model. The result is therefore a theory that generalizes, but is completely consistent with, Biot’s theory of poroelasticity and is valid for analysis of elastic wave data from highly fractured reservoirs.

  • elastic wave propagation and attenuation in a double porosity dual permeability medium
    Nevill Cook Memorial Conference Berkeley CA (US) 10 16 1998--10 17 1998, 1998
    Co-Authors: James G Berryman, Herbert F Wang
    Abstract:

    To account for large-volume low-permeability storage porosity and low-volume high-permeability fracture/crack porosity in oil and gas reservoirs, phenomenological equations for the poroelastic behavior of a double porosity medium have been formulated and the coefficients in these linear equations identified. The generalization from a single porosity model increases the number of independent inertial coefficients from three to six, the number of independent drag coefficients from three to six, and the number of independent stress-strain coefficients from three to six for an isotropic applied stress and assumed isotropy of the medium. The analysis leading to physical interpretations of the inertial and drag coefficients is relatively straightforward, whereas that for the stress-strain coefficients is more tedious. In a quasistatic analysis, the physical interpretations are based upon considerations of extremes in both spatial and temporal scales. The limit of very short times is the one most relevant for wave propagation, and in this case both matrix porosity and fractures are expected to behave in an undrained fashion, although our analysis makes no assumptions in this regard. For the very long times more relevant for reservoir drawdown, the double porosity medium behaves as an equivalent single porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the Total Compressibility) may be determined by appropriate field tests. At the mesoscopic scale pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the Compressibility can be measured for a single fracture. We show explicitly how to generalize the quasistatic results to incorporate wave propagation effects and how effects that are usually attributed to squirt flow under partially saturated conditions can be explained alternatively in terms of the double-porosity model. The result is therefore a theory that generalizes, but is completely consistent with, Biot's theory of poroelasticity and is valid for analysis of elastic wave data from highly fractur

  • the elastic coefficients of double porosity models for fluid transport in jointed rock
    Journal of Geophysical Research, 1995
    Co-Authors: James G Berryman, Herbert F Wang
    Abstract:

    Phenomenological equations (with coefficients to be determined by specified experiments) for the poroelastic behavior of a dual porosity medium are formulated, and the coefficients in these linear equations are identified. The generalization from the single-porosity case increases the number of independent coefficients for volume deformation from three to six for an isotropic applied stress. The physical interpretations are based upon considerations of different temporal and spatial scales. For very short times, both matrix and fractures behave in an undrained fashion. For very long times, the double-porosity medium behaves like an equivalent single-porosity medium. At the macroscopic spatial level, the pertinent parameters (such as the Total Compressibility) may be determined by appropriate field tests. At an intermediate or mesoscopic scale, pertinent parameters of the rock matrix can be determined directly through laboratory measurements on core, and the Compressibility can be measured for a single fracture. All six coefficients are determined from the three poroelastic matrix coefficients and the fracture Compressibility from the single assumption that the solid grain modulus of the composite is approximately the same as that of the matrix for a small fracture porosity. Under this assumption, the Total Compressibility and three-dimensional storage coefficient of the composite are the volume averages of the matrix and fracture contributions.

Masoud Alfi - One of the best experts on this subject based on the ideXlab platform.

  • time lapse application of pressure transient analysis for monitoring compressible fluid leakage
    Greenhouse Gases-Science and Technology, 2016
    Co-Authors: Seyyed A Hosseini, Masoud Alfi
    Abstract:

    Detecting early leakage of gaseous fluids from deep formations into shallower formations has financial and environmental implications and could potentially save commercial projects from expensive remediation. Detection of CO 2 leakage in the context of CO 2 geological storage and methane leakage at hydraulic‐fracturing sites is a possible scenario in which the approach described herein could be used. Any vertical leakage from a deep formation will most likely start with brine leakage, followed by arrival of the gaseous phase at the leakage pathway (faults, plugged and abandoned wells, fractures, etc.). We apply well‐known pressure transient analysis (PTA) techniques to solving challenges related to leakage monitoring, including distinguishing between brine and gaseous‐phase leakage and detecting leaks that may occur over a long period of time. The latter development is important because small leaks may not be detected by simple monitoring of absolute change in pressure. The proposed analysis is based on time‐lapse measurement of monitoring‐zone storativity (or Total Compressibility), and without loss of generality, we apply our analysis to CO 2 leakage scenarios. Our numerical results suggest that if well‐known PTA techniques are used, CO 2 leaks can be detected, allowing the volume of leaked CO 2 into the monitoring zone to be estimated. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd

Seyyed A Hosseini - One of the best experts on this subject based on the ideXlab platform.

  • time lapse application of pressure transient analysis for monitoring compressible fluid leakage
    Greenhouse Gases-Science and Technology, 2016
    Co-Authors: Seyyed A Hosseini, Masoud Alfi
    Abstract:

    Detecting early leakage of gaseous fluids from deep formations into shallower formations has financial and environmental implications and could potentially save commercial projects from expensive remediation. Detection of CO 2 leakage in the context of CO 2 geological storage and methane leakage at hydraulic‐fracturing sites is a possible scenario in which the approach described herein could be used. Any vertical leakage from a deep formation will most likely start with brine leakage, followed by arrival of the gaseous phase at the leakage pathway (faults, plugged and abandoned wells, fractures, etc.). We apply well‐known pressure transient analysis (PTA) techniques to solving challenges related to leakage monitoring, including distinguishing between brine and gaseous‐phase leakage and detecting leaks that may occur over a long period of time. The latter development is important because small leaks may not be detected by simple monitoring of absolute change in pressure. The proposed analysis is based on time‐lapse measurement of monitoring‐zone storativity (or Total Compressibility), and without loss of generality, we apply our analysis to CO 2 leakage scenarios. Our numerical results suggest that if well‐known PTA techniques are used, CO 2 leaks can be detected, allowing the volume of leaked CO 2 into the monitoring zone to be estimated. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd

Neeraj Gupta - One of the best experts on this subject based on the ideXlab platform.

  • Analyzing the Performance of Closed Reservoirs Following CO2 Injection in CCUS Projects
    Energy Procedia, 2017
    Co-Authors: Srikanta Mishra, Priya Ravi Ganesh, Mark Kelley, Neeraj Gupta
    Abstract:

    Abstract This paper discusses the use of a 2-D numerical model representing a typical depleted pinnacle reef reservoir to generate synthetic data for multiple CO2 injection periods after a prolonged period of oil and gas production. The data are analyzed with conventional pressure-transient analysis and injectivity-index approaches from petroleum reservoir engineering practice. Pressure falloff data from multiple shut-in periods, with and without boundary effects, indicate that the system response is similar to that of a composite reservoir with different Total mobility and Total Compressibility values in the inner (CO2-rich) and outer (CO2-free) regions. The Total mobility of the inner zone can be approximated by the Total mobility of the gas phase in the vicinity of the CO2-oil front, while the Total mobility of the outer zone corresponds to the Total mobility of the oil phase in the undisturbed region. The injectivity index, calculated as injection rate divided by the pressure buildup from reference conditions, yields a quasi-stable value during the transient period which can be correlated to the permeability-thickness product of the injection zone. During the boundary-dominated (pseudo-steady-state) period, a flowing material balance plot can be utilized to determine an apparent injectivity index, which is higher than the true injectivity index because of multi-phase skin effects.