Plate Tectonics (eBook)

Cover 1
Contents 6
Preface 6
Chapter 1. Plate tectonics 3
A perspective 12
Structure of the Earth 15
Seafloor spreading 16
Plate boundaries 17
The Wilson Cycle 23
Stress distribution within plates 24
Plate motions 24
Plate driving forces 28
Geomagnetism 28
Hotpots and plumes 34
Plate tectonics and organic evolution 38
Supercontinents 39
Interactions of Earth systems 44
Summary statements 45
Suggestions for further reading 46
Chapter 2. The Earth's crust 47
Introduction 47
Crustal types 47
Continent size 50
Seismic crustal structure 51
Crustal gravity 55
Crustal magnetism 56
Crustal electrical conductivity 56
Heat flow 58
Exhumation and cratonization 61
Processes in the continental crust 64
Crustal composition 65
An estimate of crustal composition 70
Crustal provinces and terranes 73
The United Plates of America 78
Summary statements 78
Suggestions for further reading 79
Chapter 3. Tectonic settings 80
Introduction 80
Ocean ridges 80
Ophiolites 81
Tectonic settings related to mantle plumes 85
Cratons and passive margins 88
Continental rifts 90
Arc systems 94
Orogens 103
Uncertain tectonic settings 109
Mineral and energy deposits 115
Summary statements 119
Suggestions for further reading 120
Chapter 4. The Earth's mantle and core 121
Introduction 121
Seismic structure of the mantle 121
Geoid anomalies 124
Electrical conductivity of the mantle 124
Temperature distribution in the mantle 125
Composition of the mantle 127
The lithosphere 130
The low-velocity zone (LVZ) 134
The transition zone 134
The lower mantle 137
Mantle plumes 138
Mantle upwellings, plumes, and supercontinents 140
Mantle geochemical components 141
Identifying mantle components 141
Convection in the mantle 145
The core 148
Summary statements 152
Suggestions for further reading 154
Chapter 5. Crustal and mantle evolution 155
Introduction 155
The Earth's thermal history 155
The Earth's primitive crust 155
The Earth's oldest rocks 157
Crustal origin 161
How continents grow 162
Plate tectonics with time 164
Episodic age distributions 165
Continental growth rates 169
Secular changes in the crust-mantle system 174
Summary of chemical changes at the Archean-Proterozoic boundary 184
Evolution of the crust-mantle system 187
Summary statements 190
Suggestions for further reading 191
Chapter 6. The atmosphere, oceans, climates, and life 192
Introduction 192
General features of the atmosphere 192
The primitive atmosphere 193
The degassed atmosphere 194
The origin of oxygen 198
Phanerozoic atmospheric history 202
The carbon isotope record 203
The sulphur isotope record 205
The oceans 205
Paleoclimates 212
Living systems 220
Mass extinctions 229
Summary statements 236
Suggestions for further reading 237
Chapter 7. Comparative planetary evolution 239
Introduction 239
Impact chronology in the inner Solar System 239
Members of the Solar System 240
Chemical composition of the Earth and Moon 253
Age of the Earth and Solar System 255
Comparative evolution of the atmospheres of 256
The continuously habitable zone 257
Condensation and accretion of the planets 258
Origin of the Moon 261
The Earth's rotational history 264
Comparative planetary evolution 265
Summary statements 267
Suggestions for further reading 269
References 270
Index 290