Volcanoes: Global Perspectives

PREFACE vii

PART I – INTRODUCTION 3

1. Eruptions, Jargon, and History 5

A “Grey Volcano” in Eruption – Galunggung – 1982 6

A “Red Volcano” in Eruption – Kilauea – 1974 16

Some Basic Terminology 22

History of Volcanology 27

Further Reading 39

Questions for Thought, Study, and Discussion 40

PART II – THE BIG PICTURE 43

2. Global Perspectives – Plate Tectonics and Volcanism 45

Birth of a Theory 45

Volcanoes along Divergent Plate Boundaries 51

Volcanoes along Convergent Plate Boundaries 53

Intraplate Volcanoes 60

Further Reading 63

Questions for Thought, Study, and Discussion 64

3. The Nature of Magma – Where Volcanoes Come From 65

Origins of Magma 65

The Physics and Chemistry of Melting 68

Classification of Magma and Igneous Rocks 72

Principal Magma Types 73

Magmatic and Volcanic Gases 78

Further Reading 86

Questions for Thought, Study, and Discussion 87

4. The Physical Properties of Magma and Why it Erupts 89

Magma Temperatures 89

Magma Rheology 91

Magma Ascent and Emplacement 94

“Frozen Magma” – Subvolcanic Intrusives 100

Triggers for Volcanic Eruptions –Why Volcanoes Erupt 105

Repose Intervals 108

Further Reading 109

Questions for Thought, Study, and Discussion 110

PART III – VOLCANIC ERUPTIONS AND THEIR PRODUCTS 113

5. Classifying Volcanic Eruptions 115

Lacroix Classification System 117

Rittman Diagrams 118

Geze Classification Diagram 119

Walker Classification System 119

Volcanic Explosivity Index (VEI) 123

Further Reading 125

Questions for Thought, Study, and Discussion 126

6. Effusive Volcanic Eruptions and Their Products 127

Mafic and Intermediate Effusive Eruptions 128

Pahoehoe and 0A0a 135

Pyroducts 138

Pahoehoe Surface Structures 147

Lava Flow Internal Structures 157

0A0a Surface Structures 162

Block Lavas 166

Radiocarbon Dating of Prehistoric Lava Flows 170

Further Reading 171

Questions for Thought, Study, and Discussion 172

7. An Overview of Explosive Eruptions and Their Products 173

Ejecta Classification 174

Explosive Eruption Styles and Their Products 188

Pyroclastic Density Currents (PDCs) 204

Further Reading 220

Questions for Thought, Study, and Discussion 221

8. A Closer Look at Large-scale Explosive Eruptions 223

Measuring the Sizes of Plinian Eruptions 224

Plinian Eruption Dynamics 224

Pyroclastic Density Currents (PDCs) 235

Directed Blasts 255

“Super-Eruptions” 258

Further Reading 261

Questions for Thought, Study, and Discussion 262

PART IV – VOLCANIC LANDFORMS AND SETTINGS 265

9. Constructional (“Positive”) Volcanic Landforms 267

Large Igneous Provinces 267

Shield Volcanoes 270

Composite Volcanoes 283

Minor Volcanic Landforms 290

Volcano Old Age and Extinction 308

Further Reading 314

Questions for Thought, Study, and Discussion 315

10. “Negative” Volcanic Landforms – Craters and Calderas 317

Small Craters 318

Calderas 321

Post-caldera Resurgence 331

Caldera Formation Mechanisms 335

Caldera Roots – Relationships to Plutonic Rocks 336

Volcano-tectonic Depressions 336

Further Reading 338

Questions for Thought, Study, and Discussion 339

11. Mass-wasting Processes and Products 341

Landslides, Avalanches, and Sector Collapses 341

Lahars 347

Causes of Lahars 350

Lahar Dynamics 354

Lahar Destructiveness 356

Further Reading 358

Questions for Thought, Study, and Discussion 359

12. Volcanoes Unseen and Far Away 361

Submarine and Subglacial Volcanoes – The Meeting of Fire, Water, and Ice 362

Extraterrestrial Volcanoes 377

Further Reading 392

Questions for Thought, Study, and Discussion 393

PART V – HUMANISTIC VOLCANOLOGY 395

13. Volcanoes: Life, Climate, and Human History 397

Volcanoes and the Origin of Life 397

Volcanoes, Atmosphere, and Climate 398

Volcanic Influence on Soil Fertility and Agriculture 406

Volcanoes and Human History 407

Social Impact of Volcanic Eruptions 408

Further Reading 411

Questions for Thought, Study, and Discussion 412

14. Volcanic Hazards and Risk – Monitoring and Mitigation 413

Hazards and Risk 414

Active, Dormant, and Extinct Volcanoes 414

Volcanic Hazards 416

Volcanic Risk 425

Volcano Monitoring 443

Volcanic Crisis Management 455

Further Reading 462

Questions for Thought, Study, and Discussion 463

15. Economic Volcanology 465

Earth Energy Relationships 465

Volcano Energy 466

Stored Energy: Geothermal Power 467

Volcanoes and Ore Deposits 470

Other Useful Volcanic Materials 475

Further Reading 477

Questions for Thought, Study, and Discussion 478

Epilogue: The Future of Volcanology 479

References 481

Index 521

Appendix: List of Prominent World Volcanoes 538

Map: Prominent World Volcanoes 540

Companion website available at www.wiley.com/go/lockwood/volcanoes