earth materials - gbv

EARTH MATERIALS Components of a Diverse Planet

DEXTER PERKINS Department of Geology and Geological Engineering, Tue University of North Dakota, Grand Forks, USA

KEVIN R. HENKE Retired, Center for Applied Energy Research, Tue University of Kentucky, Lexington, USA

ADAM C. SIMON Department of Earth and Environmental Sciences, Tue University of Michigan, Ann Arbor, USA

LANCE D. YARBROUGH Department of Geology and Geological Engineering, Tue University of Mississippi, Oxford, USA

~CRC Press 'e] Taylor & Francis Group Soca Raton London New Yori< Leiden

CRC Press ls an imprint of the Taylor & Francis Group, an lnforma business

A BALKEMA BOOK

Contents

Preface

About the Authors

Acknowledgments

Part 1 lntroduction to Earth

1 Tue Origin of the Elements and Earth 1.1 Orion 1.2 The big picture 1.3 The beginning

1.3.1 The big bang 1.3.2 Stellar evolution

1.4 Origin of the solar system 1.4.1 What makes up the solar system? 1.4.2 Solar nebula hypothesis 1.4.3 The planets 1.4.4 Dwarf planets 1.4.5 Asteroids and meteoroids 1.4.6 Classification and origin of meteorites 1.4.7 Comets

1.5 Evolution of the solar system 1.5.1 Planetesimals and formation of protoplanets 1.5.2 Differentiation of the terrestrial planets and the moon 1.5.3 Planetary atmospheres

1.6 What is Earth made of today? Questions for thought--chapter 1

2 Earth Systems and Cydes 2.1 A Sand County Almanac 2.2 The Earth system and my aquariutn

2.2.1 Earth from space 2.2.2 A simpler system

2.3 Systems and scientific investigations 2.3.1 Classification of systems 2.3.2 Earth's spheres 2.3.3 Broader views 2.3.4 System reservoirs and fluxes 2.3.5 Cycles

2.4 Rocks and the Rock Cycle 2.4.1 At Earth's surface 2.4.2 Lithification 2.4.3 Soil 2.4.4 Deeper in Earth

,\ ..

xix

xxi

xxiii

1

3 3 5 8 8 9

10 10 11 11 13 13 14 15 15 15 16 17 18 20

21 21 22 22 23 23 24 25 27 27 28 30 31 32 32 32

vi Contents

2.5 From continental drift to plate tectonics 2.5 .1 Continental drift: A hypothesis that led to the theory of plate tectonics 2.5.2 Development of the theory of plate tectonics

2.5.2.1 Mapping the ocean floor 2.5.2.2 Global seismicity 2.5.2.3 Global volcanism 2.5.2.4 Earth's magnetic field and paleomagnetism 2.5.2.5 Confirming evidence 2.5.2.6 Developing a theory

2.6 Tue theory of plate tectonics 2.6. l Dynamic Earth 2.6.2 Divergent plate boundaries: spreading zones

2.6.2.1 Mid-ocean ridges 2.6.2.2 Continental rifts

2.6.3 Convergent boundaries (plate collisions) 2.6.3.1 Subduction zones 2.6.3.2 Ocean-ocean subduction 2.6.3.3 Ocean-continent subduction 2.6.3.4 Continent-continent collisions

2.6.4 Transform plate boundaries 2.6.5 Hot spots 2.6.6 Orogenies 2.6. 7 Convection in the mande

2.7 Tue water cycle 2.8 Carbon and the carbon cycle

2.8.1 Isotopes of carbon 2.8.1.1 Carbon-14 2.8.1.2 Stahle carbon isotopes

2.8.2 Carbon in water 2.8.3 Carbon in sediments, soils, and rocks 2.8.4 Carbon in biological organisms 2.8.5 Carbon in the atmosphere

2.8.5.l Carbon dioxide 2.8.5.2 Methane 2.8.5.3 Global climate change

Questions for thought-chapter 2

Part II Fundamental Earth Materials

3 Minerals 3.1 Zeolites 3.2 Minerals defined 3.3 Importance of minerals 3.4 Studying minerals from the past to present 3.5 Elements, minerals, and rocks 3.6 Mineral formation

3.6.1 Igneous minerals 3.6.2 Aqueous minerals 3.6.3 Metamorphic minerals

33 33 34 34 35 35 35 38 38 39 41 42 42 43 44 44 44 45 45 46 48 49 52 53 54 55 55 56 56 57 58 59 59 59 59 61

63

65 65 68 68 70 72 73 73 74 74

3.6.4 Mineraloids 3.6.5 Natural and synthetic minerals 3.6.6 Biominerals

3.7 Common elements and the most common minerals 3.8 Mineral compositions

3.8.1 Solid solutions and mineral series 3.8.2 Limited solid solutions 3.8.3 Mineral varieties 3.8.4 Mineral groups

3.9 Mineral stability 3.10 Mineral classification 3.11 Mineral properties and identification

3.11.1 Crystal shape 3.11.2 Mineral appearance

3.11.2.1 Luster 3.11.2.2 Diaphaneity 3.11.2.3 Color 3.11.2.4 Streak 3.11.2.5 Luminescence 3.11.2.6 Play of colors

3.11.3 Strength and breaking of minerals 3.11.3.1 Tenacity 3.11.3.2 Fracture, cleavage, and parting 3.11.3.3 Hardness

3.11.4 Density and specific gravity 3.11.5 Magnetism of minerals 3.11.6 Electrical properties 3.11.7 Reaction to dilute hydrochloric acid 3.11.8 Other properties

Questions for thought--chapter 3

4 Mineral Crystals 4.1 Cuevo de los Cristales 4.2 Crystallography and crystal chemistry 4.3 Tue process of crystallization 4.4 lonic crystals

4.4.1 lonic size 4.4.2 Closest packi~g 4.4.3 Exceptions to closest packing 4.4.4 Coordination number 4.4.5 Pauling's rules

4.4.5.1 Rule 1: the radius ratio principle 4.4.5.2 Rule 2: bond strength 4.4.5.3 Rules 3 and 4: sharing of anions 4.4.5.4 Rule 5: the principle of parsimony

4.5 Silicate minerals 4.6 Elemental substitutions in mineral crystals

4.6.1 Simple substitutions and coupled substitutions 4.6.2 Limited and complete solid solutions

Contents vii

75 75 76 76 79 79 80 82 83 83 85 87 88 89 89 89 92 93 94 94 95 95 96 98 99 99

100 100 100 100

103 103 104 105 107 107 107 109 110 111 111 113 114 114 115 118 118 119

viii Contents

4. 7 The arrangement of atoms in crystalline solids 4.7.1 Unit cells, atoms, and symmetry in two dimensions

4.7.1.1 Point symmetry 4. 7 .1.2 Translational symmetry

4.7.2 Unit cells and symmetry in three dimensions 4.7.2.l Unit cells 4.7.2.2 Symmetry in three dimensions 4.7.2.3 Symmetry of unit cells 4.7.2.4 Symmetry of atomic arrangements and the symmetry of crystals 4.7.2.5 Crystal shapes and symmetry


5 lgneous Petrology and the Nature of Magmas 5.1 Volcanism in Yellowstone National Park 5.2 lgneous petrology

5.2.1 lgneous processes 5.2.2 Studying igneous rocks 5.2.3 Geochemistry

5.3 Magma compositions 5.3.1 Similarities 5.3.2 Differences

5.4 Magma sources 5.4.1 Where melting occurs 5.4.2 The lithosphere and the asthenosphere 5.4.3 Why melting occurs 5.4.4 Decompression melting 5.4.5 Flux melting

5.5 Magma movement 5.5.1 Buoyancy 5.5.2 Magma chambers and cooling

5.6 Different kinds of rocks 5.7 Melting of minerals and rocks

5.7.1 Congruent and incongruent melting 5.7.2 Liquidus and solidus temperatures 5.7.3 Bowen's reaction series

5.8 The importance of partial melting and partial crystallization 5.8.1 lncomplete melting 5.8.2 Equilibrium or not? 5.8.3 Fractional melting 5.8.4 Fractional crystallization 5.8.5 Other processes explaining variations in magma composition 5.8.6 Parental magmas and differentiation

5.9 The most common occurrences of melts of different compositions 5.9.1 Ultrama.fic magmas 5.9.2 Ma.fic magmas 5.9.3 lntermediate magmas 5. 9 .4 Felsic magmas

5 .10 A closer look at magma chemistry 5 .10.1 Major and minor elements 5.10.2 Incompatible and compatible elements 5.10.3 Rare earth elements


120 121 121 122 124 124 127 128 128 131 134

137 137 139 139 140 141 143 143 143 146 146 146 147 149 149 151 151 152 153 155 155 157 158 159 159 160 160 161 163 163 165 165 166 166 166 167 167 170 171 D2

Contents ix

6 Plutonic Rocks 175 6.1 Yosemite Valley 175 6.2 Plutons of different kinds 177 6.3 Minerals in igneous rocks 178

6.3.1 Primary minerals 178 6.3.2 Secondary minerals 180 6.3.3 Essential and accessory minerals 180

6.4 Different kinds of plutonic rocks 182 6.4. l The IUGS system for naming plutonic rocks 182 6.4.2 Aplite and pegmatite 185

6.5 The southeast face of El Capitan 187 6.6 The Sierra Nevada Batholith 189

6.6.1 The Gold Rush 190 6.7 The American Cordillera 190 6.8 Mafic and ultramafic plutonic rocks 191

6.8.1 Naming mafic and ultramafic rocks 191 6.8.2 Occurrences of mafic plutonic rocks 193 6.8.3 Occurrences of ultramafic plutonic rocks 194 6.8.4 Oceanic crust, lithosphere, and ophiolites 194 6.8.5 Layered mafic intrusions 196 6.8.6 Mafic dikes and sills 197 6.8.7 Mafic dike swarms 198

Questions for thought-chapter 6 199

7 Volcanoes and Their Products 201 7. 1 Tambora and Toba 201 7.2 Volcanology 203 7.3 Volcanic eruptions 204

7 .3.1 Effusive vs. explosive eruptions 204 7.3.1.1 Effusive eruptions 204 7.3.1.2 Explosive Eruptions 206

7.3.2 A spectrum of volcanic eruptions 207 7.3.3 Volcanic landforms 208

7.3.3.1 Shield volcanoes 208 7.3.3.2 Composite volcanoes 209 7.3.3.3 Small features 210 7.3.3.4 Caldera 210 7.3.3.5 Eruption columns and their deposits 212

7.4 Xenoliths and volatiles 214 7.4.1 Xenoliths 214 7.4.2 Volatiles 215 7.4.3 Hydrovolcanic eruptions 216

7.5 Classifying eruptions 217 7.5.1 Hawaiian eruptions 219 7.5.2 Strombolian eruptions 219 7.5.3 Vulcanian eruptions 219 7.5.4 Pelean eruptions 220 7.5.5 Plinian eruptions 220 7.5.6 Surtseyan eruptions 221

7.6 From magma to rock 222 7.7 Naming volcanic rocks 224

x Contents

7.7.1 Identifying rocks in the field 7.7.2 IUGS dassification

7.7.2.1 IUGS system for naming feldspathic effusive rocks 7.7.2.2 Tue TAS alternative 7.7.2.3 IUGS system for naming pyrodastic rocks


8 Sediments and Sedimentary Rocks 8.1 Sedimentation during the formation of the Appalachian Mountains 8.2 Sediment and sedimentary environments 8.3 Products of weathering and erosion

8.3.1 Different kinds of sediments 8.3.2 Clastic sediments

8.3.2.1 Mineralogical composition and grain size 8.3.2.2 Clast shapes 8.3.2.3 Sediment texture and maturity

8.4 Transportation and deposition of dastic sediment 8.4.1 Transportation by flowing water 8.4.2 Deposition by flowing water

8.4.2.1 Alluvium 8.4.2.2 Features of river deposits 8.4.2.3 Alluvial fans

8.4.3 Transportation by wind 8.4.4 Deposition by wind

8.4.4.1 Sand Dunes 8.4.4.2 Dust and loess

8.4.5 Sediment transportation by glaciers and glacial sediments 8.4.5.1 Continental ice sheets and alpine glaciers 8.4.5.2 Glacial drift 8.4.5.3 Till 8.4.5.4 Stratified drift

8.4.6 Mass movements by gravity 8.5 Diagenesis and lithification 8.6 Sedimentary layers and structures

8.6.1 Tue nature of sediments 8.6.2 Layering in sedimentary rocks 8.6.3 Variable thickness oflayering 8.6.4 Crossbedding 8.6.5 Graded bedding 8.6.6 Bedforms

8.6.6.1 Mudcracks 8.6.6.2 Raindrop marks 8.6.6.3 Flame structures

8.7 Different kinds of sedimentary rocks 8. 7.1 Siliciclastic sedimentary rocks

8.7.1.1 Mudrocks 8. 7 .1.2 Sandstones 8.7.1.3 Conglomerates 8.7.1.4 Breccias

8.7.2 Biochemical and related sedimentary rocks

225 225 225 226 228 230

231 231 233 234 234 236 237 238 239 240 240 242 242 242 244 245 245 246 246 247 247 249 249 250 251 254 256 256 256 257 257 259 259 260 260 261 261 261 261 262 264 264 265

8.7.3 Chemieal sediments and rocks 8.7 .3.1 Evaporite deposits 8.7.3.2 Saline lake deposits 8.7.3.3 Other chemieal mineral deposits

8.7.4 Carbonate rocks 8.7.4.1 Allochemieal carbonate rocks 8.7.4.2 Orthochemieal carbonate rocks

Questions for thought~hapter 8

9 Stratigraphy 9 .1 Rocks of the Grand Canyon 9 .2 Formations, groups, and members 9.3 Stratigraphy

9 .3.1 Nieholas Steno's contributions 9.3.1.1 Tue principle of original horiwntality 9 .3.1.2 Tue law of superposition 9.3.1.3 Tue principle of lateral continuity 9 .3.1.4 Tue Principle of Crosscutting Relationships 9.3.1.5 Tue principle of indusions

9.3.2 William Smith's contributions 9.4 lnterpreting the environment of deposition 9.5 Rock lithology

9.5.1 Lithologie variation 9.5.2 Different kinds of stratigraphy 9.5.3 Lithostratigraphy

9.5.3.1 Sedimentary fades 9.5.3.2 Sea level change 9.5.3.3 Stratigraphie columns 9.5.3.4 Correlations

9.5.4 Biostratigraphy 9.5.4.1 Indexfossils

9.6 Geological time 9.6.1 Chronostratigraphy 9.6.2 Completeness of the stratigraphic record

9 .6.2.1 Unconformities 9.6.2.2 Sequences

9. 7 Subsurface stratigraphy 9.7.1 Samples from deep in Earth 9.7.2 Geophysical logging 9.7.3 Seismic reßection surveys

Questions for thought~hapter 9

10 Metamorphic Rocks 10.1 Wollastonite in the Adirondack Mountains 10.2 Metamorphic rocks 10.3 Agents of metamorphism

10.3.1 Heat and temperature 10.3.2 Pressure and depth 10.3.3 Directed stress 10.3.4 Metamorphic ßuids

Contents xi

266 266 267 268 269 270 271 271

273 273 275 277 279 280 280 280 281 282 282 284 286 286 286 286 288 288 290 291 292 294 294 296 296 296 298 299 300 300 301 303

305 305 306 307 307 308 308 309

xii Contents

10.4 Metamorphic textures 10.4.1 Grain size and porphyroblasts 10.4.2 Foliated metamorphic rocks

10.4.2.1 Slate 10.4.2.2 Phyllite 10.4.2.3 Schist 10.4.2.4 Gneiss

10.4.3 Nonfoliated metamorphic rocks 10.4.3.1 Marbles 10.4.3.2 Quartzite 10.4.3.3 Other nonfoliated metamorphic rocks

10.4.4 Lineations 10.5 Metamorphic reactions

10.5.1 Metamorphic phase diagrams 10.6 Burial metamorphism 10.7 Regional metamorphism

10.7.1 Tue role of the protolith 10.7.2 Metamorphic grade and pelitic rocks 10.7.3 Mafic rocks and metamorphic facies

10.7.3.1 Barrovian and Buchan facies series 10.7.3.2 High-Temperature Facies Series 10.7.3.3 High-Pressure Facies Series

10.7.4 Mapping regional metamorphic terranes 10.8 Contact metamorphism

10.8.1 Skarns 10.9 Other types of metamorphism

10.9.1 Cataclastic metamorphism 10.9.2 Shock metamorphism


Part III Surficial Geology and Resources

11 Weathering and Solls 11.1 Mesopotamia 11.2 Weathering

11.2.1 Definition of weathering 11.2.2 Physical weathering

11.2.2.1 Ice and salt wedging 11.2.2.2 Thermal expansion and contraction 11.2.2.3 Unloading 11.2.2.4 Abrasion by wind 11.2.2.5 Abrasion at shorelines 11.2.2.6 Abrasion by Ice

11.2.3 Chemical weathering 11.2.3.1 Spheroidal weathering 11.2.3.2 Hydrolysis, oxidation, and hydration 11.2.3.3 Dissolution

11.2.4 Biological weathering

309 309 310 311 311 311 312 313 313 314 314 315 315 317 318 318 320 320 322 323 324 324 325 326 326 328 328 328 328

331

333 333 334 334 337 337 338 339 339 340 341 341 342 342 343 344

Contents xiii

11.2.5 Weathering products and rates 344 11.2.5. l Weathering rates of minerals 344 11.2.5.2 Weathering rates of rocks 346

11.3 Soil 346 11.3. l Earth's critical zone and soil 346 11.3.2 Tue importance and nature of soil 347 11.3.3 Soll profiles 348 11.3.4 Soils and agriculture 349 11.3.5 Pedogenesis (Soil formation) 351

11.3.5.1 Parent material 352 11.3.5.2 Climate 353 11.3.5.3 Topography 354 11.3.5.4 Organisms 355 11.3.5.5 Time 355

11.3.6 Characteristics of soils 356 11.3.6.1 Color 357 11.3.6.2 Temperature 357 11.3.6.3 Texture 357 11.3.6.4 Structure 358 11.3.6.5 Consistency 359 11.3.6.6 Water content and pore space 359

11.3.7 Soil classification and naming 360 11.3.8 Soil degradation 361

11.3.8.1 Erosion 361 11.3.8.2 Compaction 361 11.3.8.3 Desercification 362 11.3.8.4 Acidification 362 11.3.8.5 Contamination 363 11.3.8.6 Salination 363

Questions for thought-chapter 11 364

12 Water and the Hydrosphere 365 12.l Tue Salton Sea 365 12.2 Water on Earch 367 12.3 Tue water cycle 371 12.4 Tue ocean systems 373 12.5 Freshwater systems 376

12.5.1 Rivers and streams 376 12.5.2 Lakes 378 12.5.3 Groundwater 380

12.5.3.1 Aquifers 381 12.5.4 Tue cryosphere 384

12.5.4.1 Snow 385 12.5.4.2 Glaciers 385 12.5.4.3 lce sheets and icebergs 386 12.5.4.4 Sea ice 387 12.5.4.5 Permafrost 388

12.6 Water chemistry 388 12.6.1 Ocean water 389

xiv Contents

12.6.2 Continental waters 391 12.7 Freshwater quality 392

12.7.1 Water and human health 393 12.7.2 Ecosystem health 394

12.7.2.1 Organic matter and eutrophication 395 12.7.2.2 Thermal Pollution 396

Questions for thought--chapter 12 397

13 Mineral Deposits 399 13.1 Bingham Canyon, Utah 399

13.1.1 Why do we need Bingham Canyon? 400 13.1.2 Bingham Canyon today 401

13.2 Why dig such a big hole? 401 13.2.1 Archaeological periods and mining 401 13.2.2 Modem society and mining 403

13.3 Mineral deposits and ore deposits 404 13.4 The formation of ore deposits 404 13.5 Placer deposits 405

13.5.1 Placer gold 406 13.5.2 Placer diamonds 407 13.5.3 Placer tin 407

13.6 Chemical ore deposits 408 13.6.1 Laterite deposits 408 13.6.2 Evaporite deposits 410

13.6.2.1 Halite 411 13.6.2.2 Sylvite 411 13.6.2.3 Gypsum 412 13.6.2.4 Continental evaporites 413 13.6.2.5 Boron deposits 413 13.6.2.6 Lithium deposits 414

13.7 Sedimentary ore deposits 414 13.7.1 Phosphorous deposits 415 13.7.2 Banded iron formations 416 13.7.3 Limestone 418

13.7.3.1 Ancient roads 418 13.7.3.2 Quarrying limestone 419 13.7.3.3 Cement 419

13.8 Igneous ore deposits 420 13.8.1 Porphyry deposits 420 13.8.2 Magmatic sulfide deposits and other cumulates 421

13.9 Other kinds of ore deposits 422 13.9.1 Volcanogenic massive sulfide deposits 422 13.9.2 Mississippi valley type deposits 423

13.10 Is mining necessary? 424 13.10.1 Resources in the future 424 13.10.2 Recycling of resources 425

Questions for thought--chapter 13 426

14 Energy Resources 429 14.1 Star wars 429

~

14.2 Tue energy that we use 14.2. l Sources of energy

14.3 Fossil fuels 14.3.1 Crude oil 14.3.2 Origin of petroleum

14.3.2.1 Source rocks and migration 14.3.2.2 Petroleum reservoirs

14.3.3 Petroleum exploration and production 14.3.3.1 Drilling and recovery of oil and natural gas 14.3.3.2 Primary oil recovery 14.3.3.3 Secondary recovery 14.3.3.4 Enhanced oil recovery 14.3.3.5 Production from unconventional petroleum reservoirs

14.3.4 Tar sands oil 14.3.5 Coal 14.3.6 Origin and properties of peat and coal

14.3.6.1 Peat 14.3.6.2 Different kinds of coal 14.3.6.3 Low rank coal 14.3.6.4 Higher rank coal

14.3.7 Coal production 14.3.8 Coal mining

14.3.8.l Hazards associated with coal mining 14.3.8.2 Environmental problems associated with coal mining

14.3.9 Coal bed methane 14.4 Alternatives to fossil fuels

14.4.1 Nuclear electrical generation 14.4.2 Conventional nuclear power

14.4.2.1 Breeder reactors and fuel reprocessing 14.4.2.2 Uranium ore deposits 14.4.2.3 In situ uranium mining 14.4.2.4 What is the future for nuclear power?

14.4.3 Geothermal energy 14.4.3.1 Sources and uses of geothermal energy 14.4.3.2 Geothermal electricity 14.4.3.3 Geothermal heat pumps

14.4.4 Renewable sources of energy 14.4.4.1 Hydroelectric power 14.4.4.2 Ocean Power: Catch the Wave! 14.4.4.3 Wind energy 14.4.4.4 Solar energy

14.4.5 Waste-to-energy 14.4.5.1 lncineration 14.4.5.2 Gasification 14.4.5.3 Pyrolysis 14.4.5.4 Anaerobic digestion

14.4.6 Energy from other kinds of biomass 14.4.7 Energy from hydrogen gas

14.5 Energy sources in the future Questions for thought--chapter 14

Contents xv

430 431 432 432 434 435 435 436 437 438 438 438 439 440 440 441 441 443 443 443 444 445 446 446 447 448 448 449 450 450 451 452 454 454 454 455 457 457 458 458 460 463 463 463 463 464 464 465 466 467

xvi Contents

Part IV Engineering Properties

15 Soll Mechanics 15.1 The Leaning Tower of Pisa 15.2 Soil mechanics 15.3 Sediments, soils, and rocks 15.4 Consolidated and unconsolidated materials 15.5 Soil composition and index properties

15.5.1 Soil mineralogy 15.5.2 Grain shape, roundness, and sphericity 15.5.3 Grain size

15.5.3.1 The Wentworth scale 15.5.3.2 Krumbein phi scale

15.5.4 Grain size distribution in sediments and soils 15.5.4.1 Grain size analysis 15.5.4.2 Grain size distribution 15.5.4.3 Sorting and grading 15.5.4.4 Representative grain sizes 15.5.4.5 Hazen approximation 15.5.4.6 Coefficient of uniformity and coefficient of curvature

15.5.5 Soil phase relationships 15.5.5.1 Void ratio and porosity 15.5.5.2 Effective porosity 15.5.5.3 Saturation and water content

15.5.6 Atterberg limits 15.5.6.1 Liquid limit 15.5.6.2 Plastic limit 15.5.6.3 Shrinkage limit 15.5.6.4 Density

15.6 Soil classification 15.6.1 The USCS

15.7 Soil strength 15.7.1 Stress 15.7.2 Pressure, stress, and depth 15.7.3 Soil compaction and consolidation 15.7.4 Shear strength 15.7.5 Effect of water on strength


16 Rock Mechanics 16.1 Problems in Coeur d' Alene

16.1.1 Rock bursts 16.1.1.1 Strain bursts 16.1.1.2 Pillar bursts 16.1.1.3 Slip bursts 16.1.1.4 Hazards and engineering

16.2 Forces and stress

469

471 471 472 472 473 473 473 474 475 475 475 475 475 477 477 478 478 479 479 480 481 481 481 482 483 483 484 485 485 486 486 488 488 489 491 492

493 493 493 494 494 494 494 494

Contents xvii

16.2.1 Tue importance of stress 49S 16.2.2 Stress on rocks within Earth 496

16.3 Strain-rock deformation in response to stress 497 16.3.1 Different kinds of deformation 498 16.3.2 What determines brittle or ductile behavior? SOO 16.3.3 Different kinds of rock failure SOl

16.3.3.1 Constructing a Mohr's circle diagram S02 16.3.3.2 lnterpreting a Mohr's circle diagram S03 16.3.3.3 Failure criteria S03 16.3.3.4 Effective stress S04

16.4 On a larger scale SOS 16.4.1 Rock quality designation (RQD) S06 16.4.2 Tue geological strength index (GSI) S07

16.S Determining values for rock strength S08 16.S.1 Uniaxial compressive strength tests S08 16.S.2 Point-load tests SlO 16. S .3 Uniaxial tension strength tests S 10 16.S .4 Brazilian test S 10

16.S.4.1 Shear strength testing S 11 16.S.S Tue Schmidt hammer Sll 16.S.6 Triaxial rock testing Sl2 16.S.7 Durability tests S 12

Questions for thought--chapter 16 S 12

References 515

Index 521

earth materials - gbv

Documents