Physical Geology: Earth Revealed, 9th Edition

Cover......Page 1
Title Page......Page 4
Copyright......Page 5
Contents......Page 7
Preface......Page 14
1 Introducing Geology, the Essentials of Plate Tectonics, and Other Important Concepts......Page 28
Supplying Things We Need......Page 29
Avoiding Geologic Hazards......Page 30
Earth Systems......Page 36
Internal Processes: How the Earth’s Internal Heat Engine Works......Page 38
Earth’s Interior......Page 39
Divergent Boundaries......Page 40
Convergent Boundaries......Page 43
Surficial Processes: The Earth’s External Heat Engine......Page 45
Geologic Time......Page 50
SUMMARY......Page 51
2 Earth’s Interior and Geophysical Properties......Page 54
Evidence from Seismic Waves......Page 55
The Crust......Page 57
The Mantle......Page 58
The Core......Page 60
Isostasy......Page 63
Gravity Measurements......Page 65
Earth’s Magnetic Field......Page 66
Magnetic Reversals......Page 68
Magnetic Anomalies......Page 69
Geothermal Gradient......Page 71
Heat Flow......Page 72
SUMMARY......Page 74
3 The Sea Floor......Page 78
Methods of Studying the Sea Floor......Page 79
Continental Shelves and Continental Slopes......Page 81
Submarine Canyons......Page 83
Turbidity Currents......Page 84
Passive Continental Margins......Page 85
Abyssal Plains......Page 86
Oceanic Trenches......Page 87
Geologic Activity at the Ridges......Page 88
Fracture Zones......Page 89
Seamounts, Guyots, and Aseismic Ridges......Page 90
Reefs......Page 91
Oceanic Crust and Ophiolites......Page 93
SUMMARY......Page 96
4 Plate Tectonics......Page 100
The Early Case for Continental Drift......Page 102
Skepticism about Continental Drift......Page 104
Paleomagnetism and the Revival of Continental Drift......Page 105
Recent Evidence for Continental Drift......Page 106
Hess’s Driving Force......Page 107
Explanations......Page 108
Marine Magnetic Anomalies......Page 109
Another Test: Fracture Zones and Transform Faults......Page 112
Divergent Plate Boundaries......Page 113
Ocean-Ocean Convergence......Page 118
Continent-Continent Convergence......Page 120
The Motion of Plate Boundaries......Page 121
The Attractiveness of Plate Tectonics......Page 124
Mantle Convection......Page 125
Mantle Plumes and Hot Spots......Page 126
A Final Note......Page 127
SUMMARY......Page 131
5 Mountain Belts and the Continental Crust......Page 136
Introduction......Page 137
Ages of Mountain Belts and Continents......Page 140
Thickness and Characteristics of Rock Layers......Page 141
Metamorphism and Plutonism......Page 142
Normal Faulting......Page 143
Thickness and Density of Rocks......Page 144
Orogenies and Plate Convergence......Page 145
Post-Orogenic Uplift and Block-Faulting......Page 151
The Growth of Continents......Page 154
Displaced Terranes......Page 155
SUMMARY......Page 156
6 Geologic Structures......Page 160
Stress and Strain in the Earth’s Lithosphere......Page 161
How Do Rocks Behave When Stressed?......Page 162
Geologic Maps and Field Methods......Page 163
Folds......Page 165
Geometry of Folds......Page 166
Further Description of Folds......Page 168
Joints......Page 170
Faults......Page 172
SUMMARY......Page 179
7 Earthquakes......Page 182
Causes of Earthquakes......Page 183
Body Waves......Page 184
Surface Waves......Page 185
Determining the Location of an Earthquake......Page 186
Measuring the Size of an Earthquake......Page 188
Location and Size of Earthquakes in the United States......Page 190
Effects of Earthquakes......Page 192
Tsunami......Page 196
World Distribution of Earthquakes......Page 199
Earthquakes and Plate Tectonics......Page 202
Earthquakes at Plate Boundaries......Page 203
Earthquake Prediction and Seismic Risk......Page 204
SUMMARY......Page 210
8 Time and Geology......Page 214
The Key to the Past......Page 215
Principles Used to Determine Relative Age......Page 216
Unconformities......Page 221
Correlation......Page 223
Numerical Age......Page 226
Isotopic Dating......Page 227
Uses of Isotopic Dating......Page 232
Combining Relative and Numerical Ages......Page 233
Age of the Earth......Page 234
Comprehending Geologic Time......Page 235
SUMMARY......Page 237
9 Atoms, Elements, and Minerals......Page 242
Introduction......Page 243
Minerals and Rocks......Page 244
Atoms and Elements......Page 245
Ions and Bonding......Page 247
Crystalline Structures......Page 248
The Silicon-Oxygen Tetrahedron......Page 249
The Physical Properties of Minerals......Page 254
Streak......Page 255
Hardness......Page 256
External Crystal Form......Page 257
Cleavage......Page 259
Special Properties......Page 261
Chemical Tests......Page 262
SUMMARY......Page 264
10 Volcanism and Extrusive Rocks......Page 268
Supernatural Beliefs......Page 269
Volcanic Catastrophes......Page 272
Eruptive Violence and Physical Characteristics of Lava......Page 275
Gases......Page 277
Composition......Page 278
Extrusive Textures......Page 279
Types of Volcanoes......Page 282
Cinder Cones......Page 283
Composite Volcanoes......Page 285
Lava Floods......Page 288
Pillow Basalts......Page 293
SUMMARY......Page 295
11 Igneous Rocks, Intrusive Activity, and the Origin of Igneous Rocks......Page 300
The Rock Cycle......Page 301
A Plate Tectonic Example......Page 302
Igneous Rocks......Page 303
Identification of Igneous Rocks......Page 304
Chemistry of Igneous Rocks......Page 308
Shallow Intrusive Structures......Page 309
Intrusives That Crystallize at Depth......Page 311
Abundance and Distribution of Plutonic Rocks......Page 312
Decompression Melting......Page 313
Sequence of Crystallization and Melting......Page 314
Differentiation......Page 315
Mixing of Magmas......Page 317
Igneous Processes at Divergent Boundaries......Page 318
Intraplate Igneous Activity......Page 319
Igneous Processes at Convergent Boundaries......Page 320
SUMMARY......Page 322
12 Weathering and Soil......Page 326
Hydrosphere......Page 327
How Weathering Changes Rocks......Page 328
Mechanical Weathering......Page 329
Frost Action......Page 330
Chemical Weathering......Page 331
Role of Oxygen......Page 332
Role of Acids......Page 333
Solution Weathering......Page 334
Chemical Weathering of Feldspar......Page 335
Weathering Products......Page 336
Soil......Page 337
Soil Horizons......Page 338
Factors Affecting Soil Formation......Page 340
Soil Erosion......Page 343
Soil Classification......Page 344
SUMMARY......Page 346
Surficial Processes......Page 350
Introduction to Mass Wasting......Page 351
Type of Movement......Page 352
Gravity......Page 355
Water......Page 356
Creep......Page 357
Flow......Page 359
Rockfalls and Rockslides......Page 363
Underwater Landslides......Page 366
Preventing Mass Wasting of Soil......Page 371
Preventing Rockfalls and Rockslides on Highways......Page 372
SUMMARY......Page 373
14 Sediment and Sedimentary Rocks......Page 376
Sediment......Page 377
Transportation......Page 378
Deposition......Page 379
Lithification......Page 380
Breccia and Conglomerate......Page 381
The Fine-Grained Rocks......Page 382
Carbonate Rocks......Page 385
Evaporites......Page 389
Sedimentary Structures......Page 391
Fossils......Page 394
Formations......Page 397
Source Area......Page 398
Environment of Deposition......Page 399
Plate Tectonics and Sedimentary Rocks......Page 401
SUMMARY......Page 403
15 Metamorphism, Metamorphic Rocks, and Hydrothermal Rocks......Page 408
Introduction......Page 409
Factors Controlling the Characteristics of Metamorphic Rocks......Page 410
Temperature......Page 411
Pressure......Page 412
Fluids......Page 413
Nonfoliated Rocks......Page 414
Foliated Rocks......Page 416
Regional Metamorphism......Page 418
Pressure-Temperature Regimes......Page 422
Hydrothermal Processes......Page 424
Hydrothermal Activity at Divergent Plate Boundaries......Page 425
Metasomatism......Page 426
Hydrothermal Rocks and Minerals......Page 427
SUMMARY......Page 429
16 Streams and Floods......Page 432
Earth Systems—The Hydrologic Cycle......Page 433
Running Water......Page 434
Drainage Patterns......Page 435
Velocity......Page 436
Discharge......Page 438
Stream Erosion......Page 439
Stream Transportation of Sediment......Page 440
Bars......Page 442
Meandering Streams and Point Bars......Page 445
Flood Plains......Page 446
Deltas......Page 448
Downcutting and Base Level......Page 452
The Concept of a Graded Stream......Page 454
Stream Terraces......Page 455
Flooding......Page 457
Controlling Floods......Page 459
The Midwest Floods of 1993 and 2008......Page 463
SUMMARY......Page 465
17 Ground Water......Page 468
Porosity and Permeability......Page 469
The Water Table......Page 470
The Movement of Ground Water......Page 471
Aquifers......Page 473
Wells......Page 474
Springs and Streams......Page 475
Contamination of Ground Water......Page 477
Balancing Withdrawal and Recharge......Page 481
Caves, Sinkholes, and Karst Topography......Page 482
Other Effects......Page 484
Hot Water Underground......Page 485
Geothermal Energy......Page 486
SUMMARY......Page 488
18 Deserts and Wind Action......Page 492
Distribution of Deserts......Page 493
Some Characteristics of Deserts......Page 494
Desert Features in the Southwestern United States......Page 497
Wind Erosion and Transportation......Page 502
Wind Deposition......Page 504
SUMMARY......Page 511
19 Glaciers and Glaciation......Page 514
Introduction......Page 515
Formation and Growth of Glaciers......Page 516
Movement of Valley Glaciers......Page 519
Movement of Ice Sheets......Page 521
Glacial Erosion......Page 523
Erosional Landscapes Associated with Alpine Glaciation......Page 524
Erosional Landscapes Associated with Continental Glaciation......Page 528
Glacial Deposition......Page 529
Moraines......Page 531
Outwash......Page 533
Past Glaciation......Page 534
Direct Effects of Past Glaciation in North America......Page 537
Indirect Effects of Past Glaciation......Page 538
Evidence for Older Glaciation......Page 541
SUMMARY......Page 542
20 Waves, Beaches, and Coasts......Page 546
Water Waves......Page 547
Surf......Page 548
Rip Currents......Page 549
Beaches......Page 551
Longshore Drift of Sediment......Page 552
Human Interference with Sand Drift......Page 553
Erosional Coasts......Page 555
Depositional Coasts......Page 557
Drowned Coasts......Page 558
Uplifted Coasts......Page 559
The Biosphere and Coasts......Page 560
SUMMARY......Page 565
21 Resources......Page 568
Reserves and Resources......Page 569
Nonrenewable Energy Resources......Page 571
Renewable Energy Sources......Page 583
Ores Formed by Igneous Processes......Page 585
Ores Formed by Surface Processes......Page 588
Mining......Page 589
Fertilizers and Evaporites......Page 591
The Human Perspective......Page 592
SUMMARY......Page 594
22 The Earth’s Companions......Page 598
The Sun......Page 599
The Solar System......Page 600
The Milky Way and the Universe......Page 601
The Solar Nebula......Page 603
Other Planetary Systems......Page 605
Our Moon......Page 606
Mercury......Page 612
Venus......Page 613
Mars......Page 615
Why Are the Terrestrial Planets So Different?......Page 621
Jupiter......Page 622
Saturn......Page 623
Pluto and the Ice Dwarves......Page 625
Meteorites......Page 627
Comets......Page 628
Giant Meteor Impacts......Page 630
SUMMARY......Page 631
Appendices A–G......Page 633
Glossary......Page 645
Index......Page 657