Groundwater Geophysics: A Tool for Hydrogeology

Groundwater Geophysics – a Tool for Hydrogeology......Page 5
Contents......Page 7
Authors......Page 15
1.1 Seismic velocities......Page 18
1.1.1 Consolidated rock......Page 19
1.1.2 Unconsolidated rock......Page 21
1.1.3 Clay and till......Page 24
1.2.1 Archie´s law – conductive pore fluid and resistive rock matrix......Page 25
1.2.2 Limitations of Archie´s law – conducting mineral grains......Page 29
1.3 Electric Permittivity (Dielectricity)......Page 33
1.4 Conclusions......Page 37
1.5 References......Page 38
2.1.1 What type of waves is applied in seismic exploration?......Page 40
2.1.2 How can seismic waves image geological structure?......Page 41
2.1.3 How are seismic waves generated and recorded in the field?......Page 44
2.1.5 What kind of hydro-geologically relevant information can be obtained from seismic prospecting?......Page 46
2.2 Seismic refraction measurements......Page 48
2.2.1 Targets for seismic refraction measurements......Page 49
2.2.2 Body wave propagation in two-layer media with a plane interface......Page 50
2.2.3 Seismic refraction in laterally heterogeneous two-layer media......Page 55
2.2.4 Consistency criteria of seismic refraction measurements......Page 58
2.2.5 Field layout of seismic refraction measurements......Page 61
2.2.6 Near surface layering conditions and seismic implications......Page 63
2.2.7 Seismic interpretation approaches for heterogeneous subsurface structures......Page 66
2.2.8 Structural resolution of seismic refraction measurements......Page 75
2.3 Seismic reflection imaging......Page 80
2.3.1 Targets for seismic reflection measurements......Page 81
2.3.2 Seismic reflection amplitudes......Page 82
2.3.3 Concepts of seismic reflection measurements......Page 84
2.3.4 Seismic migration......Page 91
2.3.5 Field layout of seismic reflection measurements......Page 94
2.3.6 Problems of near surface reflection seismics......Page 96
2.3.7 Structural resolution of seismic reflection measurements......Page 97
2.5 References......Page 99
3.1 Basic principles......Page 102
3.2 Vertical electrical soundings (VES)......Page 104
3.2.2 Field measurements......Page 107
3.2.3 Sounding curve processing......Page 109
3.2.4 Ambiguities of sounding curve interpretation......Page 110
3.2.5 Geological and hydrogeological interpretation......Page 114
3.3 Resistivity mapping......Page 115
3.3.1 Square array configuration......Page 117
3.3.2 Mobile electrode arrays......Page 119
3.3.3 Mise-à-la-masse method......Page 121
3.4.1 Basic principles of streaming potential measurements......Page 122
3.4.2 Field procedures......Page 123
3.4.3 Data processing and interpretation......Page 124
3.5.1 Field equipment......Page 126
3.5.2 Field measurements......Page 127
3.5.3 Data Processing and Interpretation......Page 128
3.5.4 Examples......Page 130
3.6 References......Page 133
4.1 Introduction......Page 136
4.2 Complex conductivity and transfer function of waterwet rocks......Page 137
4.3.1 Low Frequency conductivity model......Page 140
4.3.2 Complex conductivity measurements......Page 142
4.4 Relations between complex electrical parameters and mean parameters of rock state and texture......Page 147
4.5.1 Organic and inorganic contaminants......Page 155
4.5.2 Monitoring subsurface hydraulic and migration processes......Page 158
4.5.3 Geohydraulic parameters......Page 161
4.6 References......Page 166
5.1.1 Introduction......Page 172
5.1.2 Theory......Page 173
5.1.3 Systems......Page 179
5.1.4 Data Processing......Page 182
5.1.5 Presentation......Page 183
5.2.1 Slingram and ground conductivity meters......Page 187
5.2.2 VLF, VLF-R, and RMT......Page 191
5.3 References......Page 193
6.1.1 Historic development......Page 196
6.1.2 Introduction......Page 198
6.2 Basic theory......Page 199
6.2.1 Maxwell’s equations......Page 200
6.2.2 Schelkunoff potentials......Page 201
6.2.3 The transient response over a layered halfspace......Page 203
6.2.4 The transient response for a halfspace......Page 205
6.3 Basic principle and measuring technique......Page 206
6.4.1 Current diffusion and sensitivity, homogeneous halfspace......Page 208
6.4.2 Current densities, layered halfspaces......Page 211
6.5.1 Late-time apparent resistivity......Page 213
6.6.1 Natural background noise......Page 214
6.6.2 Noise and measurements......Page 216
6.6.3 Penetration depth......Page 217
6.6.4 Model errors, equivalence......Page 218
6.7 Coupling to man-made conductors......Page 220
6.7.1 Coupling types......Page 221
6.7.2 Handling coupled data......Page 222
6.8.2 The 1D model......Page 224
6.8.3 Configurations, advantages and drawbacks......Page 225
6.9.1 Historical background and present airborne TEM systems.......Page 226
6.9.2 Special considerations for airborne measurements......Page 228
6.10.1 The SkyTEM system......Page 233
6.10.3 Processing of SkyTEM data......Page 236
6.10.4 The Hundslund Survey......Page 237
6.11 References......Page 241
7 Ground Penetrating Radar......Page 244
7.1.1 Electric permittivity and conductivity......Page 245
7.1.2 Electromagnetic wave propagation......Page 247
7.1.3 Reflection and refraction of plane waves......Page 249
7.1.5 Horizontal and vertical resolution......Page 251
7.1.6 Wave paths, traveltimes, and amplitudes......Page 252
7.1.7 Estimation of exploration depth......Page 255
7.2.2 Antennas and antenna characteristics......Page 256
7.2.3 Electronics......Page 258
7.2.4 Survey practice......Page 260
7.3.1 General processing steps......Page 262
7.3.2 Examples for GPR profiling and CMP data......Page 263
7.4 References......Page 267
8.2 NMR-Principles and MRS technique......Page 270
8.3 Survey at Waalwijk / The Netherlands......Page 278
8.4 Survey at Nauen / Germany with 2D assessment......Page 282
8.5 Current developments in MRS......Page 286
8.6 References......Page 288
9.1.1 Basic principles......Page 292
9.1.2 Magnetic properties of rocks.......Page 295
9.1.3 Field equipments and procedures......Page 297
9.1.4 Data evaluation and interpretation......Page 299
9.2 Geothermal method......Page 303
9.2.1 The underground temperature field......Page 306
9.2.2 Field procedures......Page 307
9.2.3 Interpretation of temperature data......Page 308
9.3 Radioactivity method......Page 309
9.4 References......Page 311
10.1 Physical Basics......Page 312
10.2 Gravimeters......Page 313
10.3 Gravity surveys and data processing......Page 315
10.3.1 Preparation and performance of field surveys......Page 316
10.3.2 Data processing......Page 319
10.4.1 Direct methods......Page 324
10.4.2 Indirect methods......Page 328
10.4.3 Density estimation......Page 330
10.5 Time dependent surveys......Page 331
10.6 References......Page 333
11.1 Logging tools......Page 338
11.1.1 Geotechnical tools......Page 339
11.1.2 Geophysical tools......Page 341
11.1.3 Hydroprobes......Page 343
11.1.4 Hydrogeochemical tools......Page 345
11.1.5 Miscellaneous other tools......Page 347
11.2.2 Soil gas sampling tools......Page 348
11.3 Tomographic applications......Page 349
11.5 Conclusions......Page 352
11.6 References......Page 354
12.1.2 Porosity – a key parameter for hydrogeology......Page 358
12.1.3 Physical properties of pore aquifers......Page 360
12.1.4 Geophysical survey of pore aquifers......Page 361
12.2.1 Introduction......Page 365
12.2.2 Geological and hydrological background......Page 367
12.2.3 Methods......Page 368
12.2.4 Discussion and Conclusion......Page 376
12.3.1 Study area – the island of Mors......Page 380
12.3.2 Hydrogeological mapping by the use of TEM......Page 382
12.3.3 Data collection and processing......Page 384
12.3.4 Results and discussions......Page 386
12.3.5 Conclusions......Page 396
12.4.1 Introduction......Page 398
12.4.2 Geological and hydrogeological aspects......Page 399
12.4.3 Field work and interpretation......Page 401
12.4.4 Groundwater occurrence......Page 407
12.5 References......Page 408
13.1 Hydraulic importance of fracture zones and caves......Page 412
13.2 Geophysical exploration of fracture zones: seismic methods......Page 414
13.3 Geophysical exploration of faults and fracture zones: geoelectrical methods......Page 419
13.4 Geophysical exploration of fracture zones: GPR......Page 429
13.5 Exploration of faults and fracture zones: Geophysical passive methods (self-potential, gravity, magnetic, geothermal and radioactivity methods)......Page 430
13.6 Geophysical exploration of caves......Page 435
13.7 References......Page 437
14.2 Origin of saltwater intrusions......Page 440
14.3 Electrical conductivity of saline water......Page 443
14.5 Field examples......Page 446
14.5.1 Saltwater intrusions in the North Sea region......Page 447
14.5.2 Saline groundwater in the Red Sea Province, Sudan......Page 450
14.6 References......Page 453
15.1 Definition of hydraulic conductivity and permeability......Page 456
15.2 Hydraulic conductivity related to other petrophysical parameter......Page 457
15.3.1 Resistivity......Page 460
15.3.2 Seismic velocities......Page 463
15.3.3 Nuclear resonance decay times......Page 464
15.4 Case history: Hydraulic conductivity estimation from SIP data......Page 467
15.5 References......Page 472
16.2 Vulnerability maps......Page 476
16.3 Electrical conductivity related to hydraulic resistance, residence time, and vulnerability......Page 480
16.4 Vulnerability maps based on electrical conductivity......Page 483
16.5 References......Page 487
17.1 The brownfields problem......Page 490
17.2 Mapping of waste deposits......Page 491
17.3 Mapping of abandoned industrial sites......Page 493
17.4 Mapping of groundwater contaminations......Page 497
17.4.1 Anorganic contaminants......Page 498
17.4.2 Organic contaminants......Page 500
17.5 References......Page 502
Index......Page 506