Structural Analysis and Synthesis: A Laboratory Course in Structural Geology, 3rd Revised edition

Structural Analysis and Synthesis......Page 4
Contents......Page 8
Preface......Page 11
Read This First......Page 13
Objectives......Page 14
Apparent-dip problems......Page 16
Orthographic projection......Page 17
Trigonometric solutions......Page 21
Alignment diagrams......Page 22
Objectives......Page 24
Structure contours......Page 27
The three-point problem......Page 28
Determining outcrop patterns with structure contours......Page 29
Bree Creek Quadrangle map......Page 33
Determining exact attitudes from outcrop patterns......Page 34
Determining stratigraphic thickness on slopes......Page 36
Determining stratigraphic thickness by orthographic projection......Page 38
Determining the nature of contacts......Page 39
Constructing a stratigraphic column......Page 41
Objective......Page 44
Structure sections of folded layers......Page 45
The arc method......Page 46
Drawing a topographic profile......Page 47
Structure-section format......Page 49
Objective......Page 51
A line......Page 53
Line of intersection of two planes......Page 55
Angles within a plane......Page 56
Strike and dip from two apparent dips......Page 57
Rotation of lines......Page 59
The two-tilt problem......Page 60
Cones: the drill-hole problem......Page 61
Objectives......Page 66
Fold classification based on dip isogons......Page 69
Outcrop patterns of folds......Page 70
Down-plunge viewing......Page 72
Beta (β) diagrams......Page 74
Constructing the profile of a fold exposed in flat terrain......Page 75
Simple equal-area diagrams of fold orientation......Page 76
Contour diagrams......Page 78
Determining the fold style and interlimb angle from contoured pi diagrams......Page 80
Parastic folds......Page 82
Axial-planar foliations......Page 83
Superposed folds......Page 85
Objectives......Page 89
Measuring slip......Page 91
Rotational (scissor) faulting......Page 93
Map patterns of faults......Page 95
Timing of faults......Page 96
Dynamic analysis......Page 98
Kinematic analysis......Page 103
Structural synthesis of the Bree Creek Quadrangle......Page 108
Writing style......Page 110
Common errors in geologic reports......Page 111
Elastic deformation: instantaneous, recoverable strain......Page 112
Viscous deformation: continuous strain under any stress......Page 113
Plastic deformation: continuous strain above a yield stress......Page 114
Elasticoviscous deformation......Page 115
Within every rock is a little dashpot......Page 117
Quantifying two-dimensional stress......Page 120
The Mohr diagram......Page 122
The Mohr circle of stress......Page 123
The failure envelope......Page 124
The importance of pore pressure......Page 128
Longitudinal strain......Page 131
The strain ellipse......Page 132
Three strain fields......Page 133
The coaxial deformation path......Page 134
The coaxial total strain ellipse......Page 137
Noncoaxial strain......Page 138
The noncoaxial total strain ellipse......Page 139
Deformed fossils as strain indicators......Page 140
Strain in three dimensions......Page 141
Quantifying the strain ellipsoid......Page 142
Thrust-belt ‘‘rules’’......Page 144
Recognizing ramps and flats......Page 145
Relations between folds and thrusts......Page 146
Requirements of a balanced cross section......Page 149
Constructing a restored cross section......Page 150
Constructing a balanced cross section......Page 151
Deformation mechanisms......Page 154
Fault rocks......Page 157
Kinemative indicators......Page 159
S-C fabrics......Page 160
Asymmetric porphyroclasts......Page 161
Antithetic shears......Page 162
Fundamental principles......Page 165
Triple junctions......Page 167
Focal-mechanism solutions (‘‘beach-ball’’ diagrams)......Page 168
Earth magnetism......Page 173
Apparent polar wander......Page 175
A: Measuring attitudes with a Brunton compass......Page 178
B: Geologic timescale......Page 180
C: Greek letters and their use in this book......Page 181
D: Graph for determining exaggerated dips on structure sections with vertical exaggeration......Page 182
E: Conversion factors......Page 183
F: Common symbols used on geologic maps......Page 184
G: Diagrams for use in problems......Page 185
References......Page 302
Further Reading......Page 304
Index......Page 310