Earth : evolution of a habitable world

Earth: Evolution of a Habitable World......Page 1
CONTENTS......Page 5
Preface......Page 9
Part I The astronomical planet: Earth’s place in the cosmos......Page 11
1.1 Ancient attempts to determine the scale of the cosmos......Page 13
1.2 Brief introduction to the solar system......Page 14
Summary......Page 16
Reference......Page 17
2.2 Motions of Earth in the cosmos......Page 19
2.3 Cosmic distances......Page 23
2.4 Microscopic constitution of matter......Page 27
Questions......Page 32
References......Page 33
3.1 Forces of nature......Page 35
3.3 Conservation of energy, and thermodynamics......Page 39
3.4 Electromagnetic spectrum......Page 40
3.5 Abundances in the Sun......Page 41
Summary......Page 43
References......Page 44
4.1 Stars and nuclear fusion......Page 45
4.3 Element production during nuclear fusion in stars......Page 48
4.4 Production of other elements in stars: s, r, and p processes......Page 49
4.6 Element production and life......Page 51
Questions......Page 52
References......Page 53
Part II The measurable planet: tools to discern the history of Earth and the planets......Page 55
5.2 The concept of half-life......Page 57
5.3 Carbon-14 dating......Page 59
5.4 Measurement of parents and daughters: rubidium–strontium......Page 60
5.6 Caveat emptor......Page 62
General reading......Page 63
References......Page 64
6.1 Stable isotopes, seafloor sediments, and climate......Page 65
6.2 A possible temperature history of Earth from cherts......Page 67
Summary......Page 69
References......Page 70
7.1 Process of impact cratering......Page 71
7.2 Using craters to date planetary surfaces......Page 72
7.3 Cratering on planetary bodies with atmospheres......Page 78
Questions......Page 80
References......Page 81
8.2 Estimating the age of Earth, without radioisotopes......Page 83
8.3 Geologic processes and their cyclical nature......Page 84
8.4 Principles of geologic succession......Page 86
8.5 Fossils......Page 87
8.7 Geologic timescale......Page 89
8.8 A grand sequence......Page 90
Questions......Page 91
References......Page 92
9.1 Early evidence for and historical development of plate tectonics......Page 93
9.2 Genesis of plate tectonics after World War II......Page 94
9.3 The basic model of plate tectonics......Page 97
9.4 Past motions of the plates and supercontinents......Page 101
9.5 Driving forces of plate motions......Page 104
General reading......Page 105
References......Page 106
Part III The historical planet: Earth and solar system through time......Page 107
10.1 Timescale of cosmological event leading up to solar system formation......Page 109
10.2 Formation of stars and planets......Page 110
10.3 Primitive material present in the solar system today......Page 115
10.4 The search for other planetary systems......Page 117
10.5 Summary of planet formation......Page 120
General reading......Page 121
References......Page 122
11.1 Bulk composition of the planets......Page 123
11.2 Internal structure of Earth......Page 127
11.3 Accretion: the building up of planets......Page 130
11.4 Early differentiation after accretion......Page 131
11.5 Radioactive heating......Page 132
11.7 Formation of the Moon......Page 133
11.8 Origin of Earth’s atmosphere, ocean, and organic reservoir......Page 135
11.9 The Late Heavy Bombardment......Page 136
11.10 From the Hadean into the Archean: formation of the first stable continental rocks......Page 137
Questions......Page 138
References......Page 139
12.1 Definition of life and essential workings......Page 141
12.2 The basic unit of living organisms: the cell......Page 145
12.4 Other means of utilizing energy......Page 146
12.5 Elemental necessities of life: a brief examination......Page 148
12.6 Solar system sites for life......Page 150
Summary......Page 156
Questions......Page 157
References......Page 158
13.1 Thermodynamics and life......Page 159
13.2 The raw materials of life: synthesis and the importance of handedness......Page 161
13.4 The vesicle approach and autocatalysis......Page 162
13.5 The RNA world: a second option......Page 164
13.6 The essentials of a cell and the unification of the two approaches......Page 166
13.7 The Archean situation......Page 168
Questions......Page 169
References......Page 170
14.2 The faint young Sun......Page 171
14.3 The greenhouse effect......Page 172
14.5 Implications for Earth during the faint young Sun era......Page 174
14.6 Paleosols and the carbon dioxide abundance......Page 176
14.7 Carbon dioxide cycling and early crustal tectonics......Page 177
14.8 A balance unique to Earth, and a lingering conundrum......Page 180
Questions......Page 181
References......Page 182
15.1 Venus......Page 183
15.2 Mars......Page 188
15.3 Was Mars really warm in the past?......Page 191
15.5 Implications of Venusian and Martian history for life elsewhere......Page 194
15.6 The finite life of our biosphere......Page 195
Questions......Page 196
References......Page 197
16.1 Abundances of the elements in terrestrial rocks......Page 199
16.2 Mineral structure......Page 200
16.3 Partial melting and the formation of basalts......Page 201
16.4 Formation of andesites and granites......Page 202
16.5 Formation of protocontinents in the Archean......Page 205
16.6 The Archean–Proterozoic transition......Page 206
16.7 After the Proterozoic: modern plate tectonics......Page 207
16.8 Venus: an Earth-sized planet without plate tectonics......Page 208
16.9 Water and plate tectonics......Page 209
16.10 Continents, the Moon, and the length of Earth’s day......Page 210
Questions......Page 211
References......Page 212
17.1 The modern oxygen cycle......Page 213
17.3 Limits on oxygen levels on early Earth......Page 215
17.5 Balance between oxygen loss and gain......Page 217
17.6 Reservoirs of oxygen and reduced gases......Page 218
17.7 History of oxygen on Earth......Page 219
17.8 Shield against ultraviolet radiation......Page 220
17.9 Onset of eukaryotic life......Page 221
Summary......Page 222
References......Page 223
Introduction......Page 225
18.1 Evolution......Page 227
18.2 Ediacaran–Cambrian revolution......Page 230
18.4 Cretaceous–Tertiary extinction......Page 233
18.5 A global view of Earth’s history so far......Page 237
Questions......Page 238
References......Page 239
19.1 The supercontinent cycle......Page 241
19.3 Evidence of ice ages on Earth......Page 243
19.4 Causes of the ice ages......Page 244
19.5 Cretaceous climate......Page 245
19.6 The great Tertiary cool down......Page 247
19.7 Causes of the Pleistocene ice age and its oscillations......Page 249
19.8 Saved from instability: Earth’s versus Mars’ orbital cycle......Page 251
Summary......Page 252
References......Page 253
20.2 The vagaries of understanding human origins......Page 255
20.4 The first steps: Australopithecines......Page 256
20.5 The genus Homo: Out of Africa I......Page 257
20.6 Out of Africa II......Page 258
20.7 Final act: Neanderthals and an encounter with our humanity......Page 259
20.8 This modern world......Page 263
References......Page 264
Part IV The once and future planet......Page 267
21.1 The record in ice cores......Page 269
21.2 Climate from plant pollen and packrat midden studies......Page 271
21.3 Tree rings......Page 274
21.4 Climate variability in the late Holocene......Page 276
21.5 The Younger Dryas: a signpost for the oceanic role in climate......Page 277
Summary......Page 278
References......Page 279
22.1 The records of CO2 abundance and global temperatures in modern times......Page 281
22.2 Modeling the response of Earth to increasing amounts of greenhouse gases......Page 283
22.3 Predicted effects of global warming......Page 286
22.4 The difficulty of proof: weather versus climate......Page 290
22.5 Role of the oceans in Earth’s climate......Page 291
22.6 Global warming: a long-term view......Page 293
Summary......Page 294
References......Page 295
23.1 The expanding human population......Page 297
23.2 Prospects for agriculture......Page 298
23.3 Energy resources......Page 299
23.4 Economically important minerals......Page 302
23.5 Pollution......Page 304
23.6 Can we go back?......Page 305
General reading......Page 306
References......Page 307
24 Coda: the once and future earth......Page 309
Index......Page 311