Geological Field Techniques

GEOLOGICAL FIELD TECHNIQUES......Page 5
Contents......Page 7
Preface......Page 12
Acknowledgements......Page 13
1: Introduction......Page 15
1.1 A selection of general books and reference material on geology......Page 16
1.2 Books on geological field techniques......Page 17
2.1 Introduction......Page 18
2.2 The hand lens and binoculars......Page 19
2.3 The compass-clinometer......Page 20
2.3.1 Orientation of a dipping plane......Page 25
2.3.2 Orientation of a linear feature......Page 30
2.3.3 Triangulation: Determining location using a compass......Page 34
2.4 Global positioning systems and altimeters......Page 39
2.5.1 Standard thickness and distance measurements......Page 40
2.5.2 Use of the Jacob staff to measure the thickness of inclined strata......Page 41
2.6 Classification and colour charts......Page 42
2.7 Hammer, chisels and other hardware......Page 45
2.8 The hardcopy field notebook......Page 47
2.9 The laptop, netbook or PDA as a notebook......Page 48
2.10.2 Maps and relevant literature......Page 49
2.11.2 Field safety......Page 50
2.11.3 Field safety equipment......Page 53
2.12 Conservation, respect and obtaining permission......Page 54
2.13 Further reading......Page 55
3.1.1 Defining the fieldwork objectives......Page 56
3.1.2 Deciding where to do the fieldwork......Page 57
3.2.1 Regional context......Page 59
3.2.2 Whole exposure......Page 60
3.2.3 Hand specimens......Page 63
3.3 Overview of possible data formats......Page 65
4.1 Introduction: The purposeof field notes......Page 67
4.2.2 Daily entries......Page 68
4.2.3 General tips......Page 70
4.3 Field sketches: A picture is worth a thousand words......Page 71
4.3.1 General principles: Aims, space and tools......Page 73
4.3.2 Sketches of exposures......Page 77
4.3.3 Sketching metre- and centimetre-scale features......Page 81
4.3.4 Sketch maps......Page 82
4.4.2 Notes recording interpretation, discussion and ideas......Page 86
4.5 Correlation with other data sets and interpretations......Page 91
5.1.1 Why are fossils important?......Page 93
5.1.2 Collecting fossil data......Page 94
5.2.2 Body fossil preservation......Page 96
5.2.3 Trace fossils......Page 99
5.3 Fossil distribution and where to find them......Page 101
5.3.1 Transported or life position?......Page 102
5.4.1 Sampling for biostratigraphic or evolutionary studies......Page 104
5.4.2 Sampling of bedding surfaces and palaeoecology......Page 106
5.5 Estimating abundance......Page 109
5.5.2 Quantitative measures of abundance......Page 110
5.5.3 How many samples are required?......Page 113
5.6 Summary......Page 114
5.7 Further reading......Page 115
6.1 Introduction......Page 116
6.2.1 Recording sedimentary lithology......Page 118
6.2.2 Recording sedimentary structures......Page 123
6.3 Graphic logs......Page 131
6.3.1 Conventions for graphic logs......Page 133
6.3.2 Constructing a graphic log......Page 135
6.4 Rocks in space: Reconstructings edimentary environments and their diagnostic features......Page 141
6.5 Using sedimentary rocks to interpret climate change and sea-level change......Page 147
6.5.2 Sequence stratigraphy and relative sea-level change......Page 148
6.6 Further reading......Page 151
7.1 Equipment, basic tips and safety......Page 153
7.2.1 Relationships with surrounding rocks......Page 154
7.2.2 Internal architecture: Joints and veins......Page 158
7.2.3 Internal architecture: Other exposure-scale fabrics......Page 160
7.3 Mineralogy and small-scale textures of igneous rocks......Page 168
7.3.2 Mineral texture and fabric......Page 169
7.4.1 Equipment and safety......Page 173
7.4.3 Observations......Page 174
7.5 Further reading......Page 175
8: Recording structural information......Page 177
8.1.1 Structural measurements and notations......Page 178
8.2.1 Planar brittle features – orientation......Page 179
8.2.2 Determining past motion on brittle structures......Page 184
8.3.1 Orientation of ductile planar features......Page 190
8.3.2 Direction of shear/stretching: Stretching lineations......Page 194
8.3.3 Sense of shear: Kinematic indicators......Page 196
8.3.5 Fold analysis......Page 199
8.4 Further reading......Page 205
9.1.1 Field relations and context......Page 206
9.2.1 Banding......Page 208
9.2.2 Grain textures......Page 210
9.2.3 Reaction textures......Page 211
9.3.2 Using mineral assemblages......Page 212
9.3.3 Classification of metamorphic rocks......Page 214
9.4 Unravelling metamorphism and deformation......Page 215
9.4.2 Syn-kinematic features......Page 216
9.4.3 Post-kinematic features......Page 217
9.5 Further reading......Page 219
10.1 Principles and aims......Page 220
10.2.1 Base maps and other aids......Page 221
10.2.2 Equipment for mapping......Page 226
10.3.2 Using base maps......Page 228
10.4.1 Information to record on field maps......Page 230
10.4.2 The evolving map......Page 232
10.4.3 Sketch cross-sections......Page 235
10.5 Mapping techniques......Page 236
10.5.1 Traverse mapping......Page 237
10.5.2 Contact mapping......Page 239
10.5.3 Exposure mapping......Page 240
10.5.4 Using other evidence......Page 242
10.6.1 Inking in the field map......Page 247
10.6.3 Fair copy maps......Page 249
10.6.4 Digital maps and GIS......Page 253
10.7 Further reading......Page 254
11.1 Data collection......Page 255
11.1.2 Survey grids......Page 258
11.3 Correlation with other data sets......Page 259
11.4 Further reading......Page 260
12: Photography......Page 261
13.1 Selecting and labelling samples......Page 264
13.1.2 Orientated samples......Page 265
13.1.5 Samples for fossils......Page 267
13.1.7 High-resolution sample sets......Page 268
13.1.8 Labelling samples and their packaging......Page 269
13.2.1 Packing and marking materials......Page 270
13.2.2 Extraction of samples......Page 271
14: Concluding remarks......Page 273
14.1 Further reading on scientific report writing......Page 274
References......Page 275
Appendix A1: General......Page 277
Appendix A5: Fossils......Page 279
Appendix A6: Sedimentary......Page 287
Appendix A7: Igneous......Page 307
Appendix A8: Structural......Page 310
Appendix A9: Metamorphic......Page 316
Appendix A10: Mapping......Page 320
Index......Page 324