PRINCIPLES OF STRUCTURAL GEOLOGY
Lecture 1—Introduction, Scale, & Basic Terminology1 11 Introduction 1 12 Levels of Structural Study 2 13 Types of Structural Study 2 14 Importance of Scale 3 141 Scale Terms 3 142 Scale Invariance, Fractals 4 Lecture 2 —Coordinate Systems, etc 8 21 Introduction 8 22 Three types of physical entities 8 23 Coordinate Systems 9 231 Spherical versus Cartesian Coordinate Systems10 232 Right-handed and Left-handed Coordinate Systems 10 233 Cartesian Coordinate Systems in Geology 11 24 Vectors12 241 Vectors vs Axes 12 242 Basic Properties of Vectors12 243 Geologic Features as Vectors14 244 Simple Vector Operations 17 245 Dot Product and Cross Product 18 Lecture 3 — Descriptive Geometry: Seismic Reflection2 1 31 Echo Sounding21 32 Common Depth Point (CDP) Method 23 33 Migration 25 34 Resolution of Seismic Reflection Data26 341 Vertical Resolution 26 342 Horizontal Resolution 27 35 Diffractions28 36 Artifacts 29 361 Velocity Pullup/pulldown 29 362 Multiples 29 363 Sideswipe30 364 Buried Focus 31 365 Others 32 Lecture 4 — Introduction to Deformation & Strain3 3 41 Introduction 33 42 Kinematics 33 421 Rigid Body Deformations 33 422 Strain (Non-rigid Body Deformation) 34 423 Continuum Mechanics36 424 Four Aspects of a Deforming Rock System: 37 43 Measurement of Strain 38 431 Change in Line Length:39 432 Changes in Angles: 40 433 Changes in Volume (Dilation): 41 Lecture 5 — Strain II: The Strain Ellipsoid 4 2 51 Motivation for General 3-D Strain Relations 42 52 Equations for Finite Strain43 53 Extension of a Line 43 54 Shear Strain45 Lecture 6 — Strain III: Mohr on the Strain Ellipsoid4 7 61 Introduction 47 62 Mohr’s Circle For Finite Strain 47 63 Principal Axes of Strain48 64 Maximum Angular Shear 49 65 Ellipticity50 66 Rotation of Any Line During Deformation 50 67 Lines of No Finite Elongation51 Lecture 7 — Strain IV: Finite vs Infinitesimal Strain5 3 71 Coaxial and Non-coaxial Deformation 54 72 Two Types of Rotation 55 73 Deformation Paths 55 74 Superposed Strains & Non-commutability 58 75 Plane Strain & 3-D Strain 58 Lecture 8—Stress I: Introduction 6 0 81 Force and Stress 60 82 Units Of Stress61 83 Sign Conventions:61 84 Stress on a Plane; Stress at a Point 62 85 Principal Stresses 63 86 The Stress Tensor 64 87 Mean Stress64 88 Deviatoric Stress 64 89 Special States of Stress65 Lecture 9—Vectors & Tensors6 6 91 Scalars & Vectors 67 92 Tensors 68 93 Einstein Summation Convention69 94 Coordinate Systems and Tensor Transformations 70 95 Symmetric, Asymmetric, & Antisymmetric Tensors 71 96 Finding the Principal Axes of a Symmetric Tensor 73 Lecture 10—Stress II: Mohr’s Circle7 4 101 Stresses on a Plane of Any Orientation from Cauchy’s law 74 102 A more “Traditional” Way to Derive the above Equations75 1021 Balance of Forces 76 1022 Normal and Shear Stresses on Any Plane 77 103 Mohr’s Circle for Stress78 104 Alternative Way of Plotting Mohr’s Circle80 105 Another Way to Derive Mohr’s Circle Using Tensor Transformations 81 1051 Transformation of Axes 81 1052 Tensor Transformations 82 1053 Mohr Circle Construction 82 Lecture 11—Stress III: Stress-Strain Relations 111 More on the Mohr’s Circle85 1111 Mohr’s Circle in Three Dimensions 86 112 Stress Fields and Stress Trajectories 86 113 Stress-strain Relations87 114 Elasticity88 1141 The Elasticity Tensor88 1142 The Common Material Parameters of Elasticity89 115 Deformation Beyond the Elastic Limit90 Lecture 12—Plastic & Viscous Deformation9 2 121 Strain Rate92 122 Viscosity93 123 Creep 94 124 Environmental Factors Affecting Material Response to Stress 95 1241 Variation in Stress 95 1242 Effect of Confining Pressure (Mean Stress)95 1243 Effect of Temperature 96 1244 Effect of Fluids 96 1245 The Effect of Strain Rate 97 125 Brittle, Ductile, Cataclastic, Crystal Plastic 97 Lecture 13—Deformation Mechanisms I: Elasticity, Compaction100 131 Elastic Deformation 100 132 Thermal Effects and Elasticity 102 133 Compaction103 134 Role of Fluid Pressure 104 1341 Effective Stress 105 Lecture 14—Deformation Mechanisms II: Fracture106 141 Effect of Pore Pressure111 142 Effect of Pre-existing Fractures 112 143 Friction 113 Lecture 15—Deformation Mechanisms III: Pressure Solution & Crystal Plasticity 114 151 Pressure Solution114 1511 Observational Aspects 114 1512 Environmental constrains on Pressure Solution 117 152 Mechanisms of Crystal Plasticity 117 1521 Point Defects 118 1522 Diffusion 118 1523 Planar Defects 119 Lecture 16—Deformation Mechanisms IV: Dislocations 121 161 Basic Concepts and Terms 121 162 Dislocation (“Translation”) Glide 123 163 Dislocations and Strain Hardening 123 164 Dislocation Glide and Climb 125 165 Review of Deformation Mechanisms 126 Lecture 17—Flow Laws & State of Stress in the Lithosphere 127 171 Power Law Creep 127 172 Diffusion Creep 129 173 Deformation Maps 129 174 State of Stress in the Lithosphere 130 Lecture 18—Joints & Veins 133 181 Faults and Joints as Cracks 133 182 Joints 133 1821 Terminology 134 1822 Surface morphology of the joint face: 135 1823 Special Types of Joints and Joint-related Features 136 1824 Maximum Depth of True Tensile Joints 136 183 Veins 137 1831 Fibrous Veins in Structural Analysis 138 1832 En Echelon Sigmoidal Veins 139 184 Relationship of Joints and Veins to other Structures 140 Lecture 19—Faults I: Basic Terminology 141 191 Descriptive Fault Geometry 141 192 Apparent and Real Displacement 142 193 Basic Fault Types 143 1931 Dip Slip 143 1932 Strike-Slip 143 1933 Rotational fault 144 194 Fault Rocks 144 1941 Sibson’s Classification 144 1942 The Mylonite Controversy 146 Lecture 20—Faults II: Slip Sense & Surface Effects147 201 Surface Effects of Faulting 147 2011 Emergent Faults 147 2012 Blind Faults 149 202 How a Fault Starts: Riedel Shears149 2021 Pre-rupture Structures 150 2022 Rupture & Post-Rupture Structures 151 203 Determination of Sense of Slip 151 Lecture 21—Faults III: Dynamics & Kinematics157 211 Introduction 157 212 Anderson’s Theory of Faulting 158 213 Strain from Fault Populations161 2131 Sense of Shear 161 2132 Kinematic Analysis of Fault Populations 161 2133 The P & T Dihedra 162 214 Stress From Fault Populations1 164 2141 Assumptions 164 2142 Coordinate Systems & Geometric Basis 165 2143 Inversion Of Fault Data For Stress 167 215 Scaling Laws for Fault Populations169 Lecture 22—Faults IV: Mechanics of Thrust Faults170 221 The Paradox of Low-angle Thrust Faults 170 222 Hubbert & Rubey Analysis 170 223 Alternative Solutions 174 Lecture 23—Folds I: Geometry178 231 Two-dimensional Fold Terminology 178 232 Geometric Description of Folds 180 2321 Two-dimensional (Profile) View: 180 2322 Three-dimensional View: 181 233 Fold Names Based on Orientation 182 234 Fold Tightness 183 Lecture 24 — Folds II: Geometry & Kinematics184 241 Fold Shapes 184 242 Classification Based on Shapes of Folded Layers 185 243 Geometric-kinematic Classification: 186 2431 Cylindrical Folds 186 2432 Non-Cylindrical Folds 188 244 Summary Outline 189 245 Superposed Folds 189 Lecture 25—Folds III: Kinematics191 251 Overview 191 252 Gaussian Curvature 191 253 Buckling 192 254 Shear Parallel to Layers 193 2541 Kink folds195 2542 Simple Shear during flexural slip196 255 Shear Oblique To Layers 196 256 Pure Shear Passive Flow 197 Lecture 26—Folds IV: Dynamics198 261 Basic Aspects 199 262 Common Rock Types Ranked According to “Competence” 199 263 Theoretical Analyses of Folding 199 2631 Nucleation of Folds 200 2632 Growth of Folds 201 2633 Results for Kink Folds 202 Lecture 27—Linear Minor Structures203 271 Introduction to Minor Structures 203 272 Lineations 203 2721 Mineral Lineations 203 2722 Deformed Detrital Grains (and related features) 204 2723 Rods and Mullions 205 273 Boudins 205 274 Lineations Due to Intersecting Foliations 206 Lecture 28—Planar Minor Structures I 207 281 Introduction to Foliations 207 282 Cleavage 207 2821 Cleavage and Folds 208 283 Cleavage Terminology 209 2831 Problems with Cleavage Terminology 210 2832 Descriptive Terms 210 284 Domainal Nature of Cleavage 211 2841 Scale of Typical Cleavage Domains 212 Lecture 29—Planar Minor Structures II: Cleavage & Strain 213 291 Processes of Foliation Development 213 292 Rotation of Grains 213 2921 March model 214 2922 Jeffery Model 214 2923 A Special Case of Mechanical Grain Rotation 214 293 Pressure Solution and Cleavage 215 294 Crenulation Cleavage 216 295 Cleavage and Strain 217 Lecture 30—Shear Zones & Transposition219 301 Shear Zone Foliations and Sense of Shear 219 3011 S-C Fabrics 219 3012 Mica “Fish” in Type II S-C Fabrics 219 3013 Fractured and Rotated Mineral Grains 220 3014 Asymmetric Porphyroclasts 220 302 Use of Foliation to Determine Displacement in a Shear Zone 221 303 Transposition of Foliations 222 Lecture 31—Thrust Systems I: Overview & Tectonic Setting225 311 Basic Thrust System Terminology 225 312 Tectonic Setting of Thin-skinned Fold & Thrust Belts