Well Logging for Earth Scientists
692 pages | Springer; 2nd edition (May 1, 2008) | ISBN-10: 1402037384 | PDF | 21 Mb
Well logging lies at the intersection of applied geophysics, petroleum and geotechnical engineering. It has its roots in the tentative electrical measurements in well bores which were made by the Schlumberger brothers some 80 years ago in the earliest days of systematic petroleum exploration. Today, a variety of specialized instruments is used to obtain measurements from the borehole during, as well as after, the drilling process. This readable and authoritative treatment of the physics of these measurements dispels the "black magic" of well log interpretation by relating them, including those obtained by the latest generation of tools, to rock physics. It offers a thorough exposé of the physical basis of borehole geophysical measurements, as well as an introduction to practical petrophysics -- extracting desired properties from well log measurements.
content
1.1 Introduction
1.2 What is Logging?
1.2.1 What is Wireline Logging?
1.2.2 What is LWD?
1.3 Properties of Reservoir Rocks
1.4 Well Logging: The Narrow View
1.5 Measurement Techniques
1.6 How is Logging Viewed by Others?
2.1 Introduction
2.2 Rudimentary Interpretation Principles
2.3 The Borehole Environment
2.4 Reading a Log
2.5 Examples of Curve Behavior and Log Display
2.6 A Sample Rapid Interpretation
3.1 Introduction
3.2 The Concept of Bulk Resistivity
3.3 Electrical Properties of Rocks and Brines
3.4 Spontaneous Potential
3.5 Log Example of the SP
4.1 Introduction
4.2 Early Electric Log Interpretation
4.3 Empirical Approaches to Interpretation
4.3.1 Formation Factor
4.3.2 Archie’s Synthesis
4.4 A Note of Caution
4.4.1 The Porosity Exponent, m
4.4.2 The Saturation Exponent, n
4.4.3 Effect of Clay
4.4.4 Alternative Models
4.5 A Review of Electrostatics
4.6 A Thought Experiment for a Logging Application
4.7 Anisotropy
5.1 Introduction
5.2 Unfocused Devices
5.2.1 The Short Normal
5.2.2 Estimating the Borehole Size Effect
5.3 Focused Devices
5.3.1 Laterolog Principle
5.3.2 Spherical Focusing
5.3.3 The Dual Laterolog
5.3.4 Dual Laterolog Example
5.4 Further Developments
5.4.1 Reference Electrodes
5.4.2 Thin Beds and Invasion
5.4.3 Array Tools
6.1 Introduction
6.2 Microelectrode Devices
6.3 Uses for Rxo
6.4 Azimuthal Measurements
6.5 Resistivity Measurements While Drilling
6.5.1 Resistivity at the Bit
6.5.2 Ring and Button Measurements
6.5.3 RAB Response
6.5.4 Azimuthal Measurements
6.6 Cased-Hole Resistivity Measurements
7.1 Introduction
7.2 Review of Magnetostatics and Induction
7.2.1 Magnetic Field from a Current Loop
7.2.2 Vertical Magnetic Field from a Small Current Loop
7.2.3 Voltage Induced in a Coil by a Magnetic Field
7.3 The Two-Coil Induction Device
7.4 Geometric Factor for the Two-coil Sonde
7.5 Focusing the Two-coil Sonde
7.6 Skin Effect
7.7 Two-Coil Sonde with Skin Effect
7.8 Multicoil Induction Devices
7.9 Induction or Electrode?
7.10 Induction Log Example
8.1 Introduction
8.2 Phasor Induction
8.2.1 Inverse Filtering
8.3 High Resolution Induction
8.4 Multi-Array Inductions
8.4.1 Multi-Array Devices
8.4.2 Multi-Array Processing
8.4.3 Limitations of Resolution Enhancement
8.4.4 Radial and 2D Inversion
8.4.5 Dipping Beds
8.5 Multicomponent Induction Tools and Anisotropy
8.5.1 Response of Coplanar Coils
8.5.2 Multicomponent Devices
9.1 Introduction
9.2 Characterizing Dielectrics
9.2.1 Microscopic Properties
9.2.2 Interfacial Polarization and the Dielectric Properties of Rocks
9.3 Propagation in Conductive Dielectric Materials
9.4 Dielectric Mixing Laws
9.5 The Measurement of Formation Dielectric Properties
9.6 2 MHz Measurements
9.6.1 Derivation of the Field Logs
9.6.2 General Environmental Factors
9.6.3 Vertical and Radial Response
9.6.4 Dip and Anisotropy
9.6.5 Array Propagation Measurements and their Interpretation
10.1 Introduction
10.2 Nuclear Radiation
10.3 Radioactive Decay and Statistics
10.4 Radiation Interactions
10.5 Fundamentals of Gamma Ray Interactions
10.6 Attenuation of Gamma Rays
10.7 Gamma Ray Detectors
10.7.1 Gas-Discharge Counters
10.7.2 Scintillation Detectors
10.7.3 Semiconductor Detectors
11.1 Introduction
11.2 Sources of Natural Radioactivity
11.3 Gamma Ray Devices
11.4 Uses of the Gamma Ray Measurement
11.5 Spectral Gamma Ray Logging
11.5.1 Spectral Stripping
11.6 Developments in Spectral Gamma Ray Logging
11.7 A Note on Depth of Investigation
12.1 Introduction
12.2 Density and Gamma Ray Attenuation
12.2.1 Density Measurement Technique
12.2.2 Density Compensation
12.3 Lithology Logging
12.3.1 Photoelectric Absorption and Lithology
12.3.2 Pe Measurement Technique
12.3.3 Interpretation of Pe
12.4 Inversion of Forward Models with Multidetector Tools
12.5 LWD Density Devices
12.6 Environmental Effects
12.7 Estimating Porosity from Density Measurements
12.7.1 Interpretation Parameters
13.1 Introduction
13.2 Fundamental Neutron Interactions
13.3 Nuclear Reactions and Neutron Sources
13.4 Useful Bulk Parameters
13.4.1 Macroscopic Cross Sections
13.4.2 Lethargy and Average Energy Loss
13.4.3 Number of Collisions to Slow Down
13.4.4 Characteristic Lengths
13.4.5 Characteristic Times
13.5 Neutron Detectors
14.1 Introduction
14.2 Use of Neutron Porosity Devices
14.3 Types of Neutron Tools
14.4 Basis of Measurement
14.5 Historical Measurement Technique
14.6 A Generic Thermal Neutron Tool
14.7 Typical Log Presentation
14.8 Environmental Effects
14.8.1 Introduction to Correction Charts
14.9 Major Perturbations of Neutron Porosity
14.9.1 Lithology Effect
14.9.2 Shale Effect
14.9.3 Gas Effect
14.10 Depth of Investigation
14.11 LWD Neutron Porosity Devices
14.12 Summary
15.1 Introduction
15.2 Thermal Neutron Die-Away Logging
15.2.1 Thermal Neutron Capture
15.2.2 Measurement Technique
15.2.3 Instrumentation
15.2.4 Interpretation
15.3 Pulsed Neutron Spectroscopy
15.3.1 Evolution of Measurement Technique
15.4 Pulsed Neutron Porosity
15.5 Spectroscopy
16.1 Introduction
16.1.1 Nuclear Resonance Magnetometers
16.1.2 Why Nuclear Magnetic Logging?
16.2 A Look at Magnetic Gyroscopes
16.2.1 The Precession of Atomic Magnets
16.2.2 Paramagnetism of Bulk Materials
16.3 Some Details of Nuclear Induction
16.3.1 Longitudinal Relaxation, T1
16.3.2 Rotating Frame
16.3.3 Pulsing
16.3.4 Transverse Relaxation, T2, and Spin Dephasing
16.3.5 Spin Echoes
16.3.6 Relaxation and Diffusion in Magnetic Gradients
16.3.7 Measurement Sensitivity
16.4 NMR Properties of Bulk Fluids
16.4.1 Hydrogen Index
16.4.2 Bulk Relaxation in Water and Hydrocarbons
16.4.3 Viscosity Correlations for Crude Oils
16.5 NMR Relaxation in Porous Media
16.5.1 Surface Interactions
16.5.2 Pore Size Distribution
16.5.3 Diffusion Restriction
16.5.4 Internal Magnetic Gradients
16.6 Operation of a First Generation Nuclear Magnetic Logging Tool
16.7 The NMR Renaissance of “Inside-Out” Devices
16.7.1 A New Approach
16.7.2 Numar/Halliburton MRIL
16.7.3 Schlumberger CMR and Subsequent Developments
16.7.4 LWD Devices
16.8 Applications and Log Examples
16.8.1 Tool Planners
16.8.2 Porosity and Free-Fluid Porosity
16.8.3 Pore Size Distribution and Permeability Estimation
16.8.4 Fluid Typing
16.9 Summary
16.10 Appendix A: Diffusion
17.1 Introduction to Acoustic Logging
17.2 Short History of Acoustic Measurements in Boreholes
17.3 Applications of Borehole Acoustic Logging
17.4 Review of Elastic Properties
17.5 Wave Propagation
17.6 Rudimentary Acoustic Logging
17.7 Rudimentary Acoustic Interpretation
18.1 Introduction
18.2 A Review of Laboratory Measurements
18.3 Porolelastic Models of Rocks
18.4 The Promise of Vp/Vs
18.4.1 Lithology
18.4.2 Gas Detection and Quantification
18.4.3 Mechanical Properties
18.4.4 Seismic Applications (AVO)
18.5 Acoustic Waves in Boreholes
18.5.1 Borehole Flexural Waves
18.5.2 Stoneley Waves
19.1 Introduction
19.2 Transducers – Transmitters and Receivers
19.3 Traditional Sonic Logging
19.3.1 Some Typical Problems
19.3.2 Long Spacing Sonic
19.4 Evolution of Acoustic Devices
19.4.1 Arrays of Detectors
19.4.2 Dipole Tools
19.4.3 Shear Wave Anisotropy and Crossed Dipole Tools
19.4.4 LWD
19.4.5 Modeling-driven Tool Design
19.5 Acoustic Logging Applications
19.5.1 Formation Fluid Pressure
19.5.2 Mechanical Properties and Fractures
19.5.3 Permeability
19.5.4 Cement Bond Log
19.6 Ultrasonic Devices
19.6.1 Pulse-Echo Imaging
19.6.2 Cement Evaluation
20.1 Introduction
20.2 Why are HA/HZ Wells Different?
20.3 Measurement Response
20.3.1 Resistivity
20.3.2 Density
20.3.3 Neutron
20.3.4 Other Measurements
20.4 Geosteering
20.4.1 Deep Reading Devices for Geosteering
21.1 Introduction
21.2 What is Clay/Shale?
21.2.1 Physical Properties of Clays
21.2.2 Total Porosity and Effective Porosity
21.2.3 Shale Distribution
21.2.4 Influence on Logging Measurements
21.3 Shale Determination from Single Measurements
21.3.1 Interpretation of Pe in Shaly Sands
21.3.2 Neutron Response to Shale
21.3.3 Response of _ to Clay Minerals
21.4 Neutron–Density Plots
21.5 Elemental Analysis
21.6 Clay Typing
22.1 Introduction
22.2 Graphical Approach for Binary Mixtures
22.3 Combining Three Porosity Logs
22.3.1 Lithology Logging: Incorporating Pe
22.3.2 Other Methods
22.4 Numerical Approaches to Lithology Determination
22.4.1 Quantitative Evaluation
22.5 General Evaluation Methods
23.1 Introduction
23.2 Clean Formations
23.3 Shaly Formations
23.3.1 Early Models
23.3.2 Double Layer Models
23.3.3 Saturation Equations
23.3.4 Laminated Sands
23.4 Carbonates and Heterogeneous Rocks
23.5 Permeability from Logs
23.5.1 Resistivity and Porosity
23.5.2 Petrophysical Models