Petrophysical Characterization and Fluids Transport in Unconventional Reservoirs

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Petrophysical Characterization and
Copyright
Contributors
Preface
Part 1: Petrophysical Characterization
1
Characterizing Pore Size Distributions of Shale
Introduction
Scanning Electron Microscopy
Sample Preparation
Image Analysis
Bakken Example Analysis
Gas Adsorption
Sample Preparation
Longmaxi Sample Analysis
Model Choice
Mercury Intrusion Capillary Pressure Test
Case Study
Comparison of the PSD from MICP and Gas Adsorption
Conclusions
Acknowledgments
References
2
Petrophysical Characterization of the Pore Structure of Coal
Introduction
Samples, Experiments and Methods
Samples
NMR Theory and Experiments
Theory of Centrifuge Experiment
T2 Distributions of the Coal Samples
Determination of T2 Cutoff Value
Pore Structure Characterization Using NMR
Pore Classification Based on an NMR Fluid Typing Method
Characterization of Pore Size Distribution
Characterization of Porosity
Characterization of Permeability
Conclusions
Acknowledgments
References
3
Characterization of Petrophysical Properties in Tight Sandstone Reservoirs
Introduction
Characterization and Analysis of Tight Sandstone Pore Structures
Pore Structure Characterization With Thin Section, FE-SEM, and X-CT
Pore Structure Characterization With HPMI
Pore Structure Characterization With RMI
Pore Structure Characterization With NMR
Pore Structure Characterization With N2GA
Petrophysical Properties of Tight Sandstone
Intrinsic Permeability of Tight Sandstone
Apparent Gas Permeability of Tight Sandstone
Liquid Permeability of Tight Sandstone
Low-Velocity Non-Darcy Flow in Tight Sandstone
Conclusions
Acknowledgments
References
4
Multifractal Analysis of Pore Structure of Tight Oil Reservoirs Using Low-Field NMR Measurements
Introduction
Methodology
Multifractal Theory
Relationship Between NMR T2 Time and Pore Size
Samples and Experiments
Petrophysical Parameters and Mineralogical Characteristics
Multifractal Characteristics
Relationship Between Mineral Contents and Multifractal Parameters
Relationship Between Petrophysical and Multifractal Parameters
Comparison With Sandstone Reservoirs
Conclusions
Acknowledgment
References
5
Investigation and Quantitative Evaluation of Organic-Related Pores in Unconventional Reservoirs
Introduction
Materials and Methods
Geological Settings
Low-Field NMR Test
Petrophysical Measurements
Geochemical Experiments
Petrographic and Mineralogy Analysis
Quantification of the Organic-Related Pores
Relationship With Geochemical Parameters
Prediction Using Petrophysical Data
Conclusions
Acknowledgments
References
6
Permeability of Fractured Shale and Two-Phase Relative Permeability in Fractures
Introduction
Experimental Observations
Transport Processes in Shale
Shale Permeability Measurement Techniques
Permeability Modeling
Matrix Permeability
Fracture Permeability
Combined Fracture-Matrix System Permeability
Finite-difference grid for fractures
Finite-difference grid for organic and inorganic matter
Relative Permeability in Shale Fractures
Two-Phase Flow Relative Permeability
Relative Permeability of Gas and Water in Utica Shale Sample
Field-Scale Permeability
Permeability of Shale Using History-Matching
Drawback of conventional history-matching methods
Prospective methods to estimate shale permeability by history-matching
An example of shale permeability prediction using history-matching
Permeability of Shale Using Well Logs
Limitations of well log responses in shale
Prospective methods to estimate shale permeability using well logs
Summary and Conclusions
Acknowledgments
References
7
Pore Structure, Wettability, and Their Coupled Effects on Tracer-Containing Fluid Migration in Organic-Rich Shale
Introduction
Samples and Methods
TOC and XRD Analyses
Mercury Intrusion Capillary Pressure
Spontaneous Imbibition and Contact Angle Measurement
Saturated Diffusion With Tracer-Containing API Brine
Composition Characteristics in the Longmaxi Shale
Pore Structure Characteristics
Connectivity from SI Tests
Wettability
Wettability From SI Tests
Wettability From Contact Angle Measurement
Coupled Effects of Pore Structure and Wettability on Tracer-Containing API Brine Migration
Conclusions
Acknowledgments
References
8
Tight Rock Wettability and Its Relationship With Petrophysical Properties
Introduction
Materials and Methods
Core Properties
Fluid Properties
Comparative Behavior of Oil and Water Imbibition in Tight Rocks
Spontaneous Imbibition on Dry Core Plugs
Spontaneous Imbibition on Partly Saturated Core Plugs
Contact Angle Measurement
Results and Discussions
Tight Rocks Wettability Evaluated by Spontaneous Imbibition Experiments
Spontaneous Imbibition on Partly Saturated Core Plugs
Relationship Between the Spontaneous Imbibition Results and Other Petrophysical Properties
Conclusion
Acknowledgments
References
Part 2: Porous Flow Dynamics
9
Flow Mechanism of Fractured Low-Permeability Reservoirs
Introduction
Simple Fracture Model
Complex Fracture Model
Bi-wing asymmetrical fracture
Multibranch fracture
Horizontal wells with multiple curved fractures
Mathematical Model of a Fracture Wing
Reservoir Flow Model
Fracture Wing Flow Model
Coupling
Mathematical Model of Multi-Wing Fractures
Semi-Analytical Solution
Fluid Flow in Low Permeability Reservoir
PTA of an Asymmetrical Planar Fracture
PTA of an Asymmetrical Nonplanar Fracture
PTA of Multiple Fracture Wings Connected to a Vertical Well
PTA of Multi-Wing Nonplanar Fractures in a Horizontal Well
Well Test Analysis of Multi-Wing Fractured Well Using Synthetic Data
Sample calculations
Conclusion
Dimensionless Definitions
Derivation of the Fluid Flow Equation of a Fracture Wing
Unit Conversion Factors
Acknowledgment
References
10
Heat Transfer in Enhanced Geothermal Systems: Thermal-Hydro-Mechanical Coupled Modeling
Introduction
Analytical Solution
Numerical Model Description
Thermal Drawdown Behavior
Thermal Front Propagation
Conclusions
Acknowledgments
References
11
Pore-Scale Modeling and Simulation in Shale Gas Formations
Overview of the Transport and Storage Mechanisms of Shale Gas in Organic Nanopores
Confinement Effect
Effective mean free path/effective viscosity
Slip boundary condition
Adsorption and Surface Diffusion
Molecular Simulation (Microscopic Approach)
Basics
Molecular interactions
Periodic boundary condition
Ensemble
Monte Carlo Molecular Simulation
Molecular Dynamics Simulation
Lattice Boltzmann Method (Mesoscopic Approach)
Lattice Boltzmann Models for Gaseous Flows at the Micro-/Nanoscale
LBM with BGK approximation
Effective relaxation time
Boundary conditions in LBM
Adsorbed layer
Pore-Scale LBM Characterization of Petrophysical Properties of Shale Rock
Summary
Acknowledgments
References
12
High-Pressure Methane Adsorption in Shale
Introduction
High-Pressure Methane Adsorption Experiments in Shale
Supercritical Methane Adsorption Characteristics
Excess Adsorption Models
High-Pressure Methane Adsorption Mechanism
Conclusions
Acknowledgments
References
13
Coal Permeability Modeling Considering Nonconstant Vertical Stress Condition
Introduction
Model Development
Model Validation
The Impact of Roof and Coal Properties on Permeability
Impact of New Permeability Model on Gas Production
Model Discussion
Conclusions
References
14
Dynamic Gas Flow in Coals and Its Evaluation
Introduction
Prediction Model of Permeability Change in Anthracite
Calculation of Key Parameters
Mean pore radius
Tangential momentum accommodation coefficient
Experiment to Determine Key Parameters
Permeability Change and Pore Size Evolution
Under constant effective stress conditions
Under constant gas pressure conditions
Coupling of the Permeability Change With Pore Size Evolution
Evaluation on Dynamic Flow Process
Evaluation Method
Primary Tests
Dynamic Behavior of Gas Flow in Different Coal Ranks
Impact of Coal Ranks on Dynamic Gas Flow
Conclusions
Acknowledgments
References
15
Multiphysical Flow Behavior in Shale and Permeability Measurement by Pulse-Decay Method
Introduction
Multiphysics in the Shale Reservoirs
Gas Permeability Evolution During Gas Depletion
Step 1-The Geomechanical Effect
Step 2-Slip Flow and Pore Diffusion
Step 3-Adsorption Layer Effect
Step 4-Surface Diffusion
Analytical Solutions for Pulse-Decay Experiments
The Relationship Between Porosity and Adsorption of Adsorptive Gas
The Relationship Between Porosity, Adsorption, and Permeability
Conclusions
Acknowledgments
References
Index