Archean Crustal Evolution

Archean Crustal Evolution......Page 4
Copyright Page......Page 5
Contributing authors......Page 6
Contents......Page 8
INTRODUCTION......Page 16
Spinifex texture......Page 26
Layering......Page 34
Chemical compositions......Page 37
Chemical types......Page 49
The origin of komatiite magma......Page 51
Komatiites as mantle witnesses......Page 53
Summary......Page 54
References......Page 55
Introduction......Page 60
Greenstone belt assemblage types......Page 67
Relations between assemblages......Page 83
Discussion......Page 85
Summary......Page 89
References......Page 90
Introduction......Page 100
Greenstone tectonic assemblages and terranes......Page 102
Greenstone geochemistry......Page 111
Discussion......Page 121
Summary......Page 126
References......Page 127
Introduction......Page 136
Geologic settings of Archean sedimentary rocks......Page 139
Principal types of sedimentary rocks in Archean greenstone belts......Page 140
Archean greenstone-belt sedimentary associations......Page 159
Discussion......Page 167
Summary......Page 173
References......Page 175
Evidence from the 3.2–2.9 Ga record......Page 186
Evidence from the 2.7–2.5 Ga record......Page 202
Discussion and broader implications......Page 211
Conclusions......Page 213
References......Page 214
Introduction......Page 220
Field data and petrology......Page 222
Geochemical characteristics......Page 225
Petrogenesis......Page 232
Comparison between Archean and modern granitoids......Page 242
Discussion......Page 257
Summary......Page 261
References......Page 262
Introduction......Page 276
Geologic setting of Archean granite plutons......Page 277
A normalization diagram for granite plutons......Page 284
Chemical compositions of calc-alkaline granite plutons......Page 287
Chemical compositions of strongly peraluminous granite plutons......Page 300
Chemical compositions of alkaline granite plutons......Page 308
Heat sources......Page 315
Tectonic environment......Page 318
Summary......Page 319
Acknowledgements......Page 320
References......Page 321
Introduction......Page 330
Field relations......Page 331
Magmatic textures and structures......Page 332
Petrology and geochemistry......Page 337
Ages and isotopic compositions......Page 347
Descriptions of selected occurrences of archean anorthosites......Page 348
Origin of Archean anorthosites......Page 360
Summary......Page 365
References......Page 366
Introduction......Page 372
Archean metamorphism: general concepts......Page 374
High-grade metamorphism: tools......Page 375
Superior Province: three types of granulite in a single craton......Page 378
High-pressure metamorphism......Page 390
High-temperature metamorphism......Page 392
Carbonic fluids in high-grade metamorphism......Page 394
Repeated granulite-facies metamorphism......Page 397
Archean lower-crustal granulite xenoliths......Page 399
Archean granulites and continental collision......Page 400
Archean granulite metamorphism and magmatism......Page 401
Archean geothermal gradients......Page 405
Comparison with younger high-grade metamorphic belts......Page 407
Summary......Page 409
References......Page 411
Introduction......Page 426
Aldan Province......Page 431
Stanovoy Province......Page 438
Olenek Province......Page 443
Anabar Province......Page 447
Magan Province......Page 450
Tungus Province......Page 451
Yenisey Province......Page 455
Akitkan orogenic belt......Page 457
Angara orogenic beltt......Page 459
Discussion......Page 461
Acknowledgments......Page 466
References......Page 467
Introduction......Page 476
Classification of Archean terrains......Page 478
Synvolcanic deposits in greenstone belts......Page 479
Syn- to post-orogenic deposits in greenstone belts......Page 492
Metallogenic synthesis......Page 501
Summary......Page 508
References......Page 509
Origin of the atmosphere......Page 520
Geologic evidence for the composition of the 3.8–3.0 Ga atmosphere......Page 521
Processes that shaped the Archean atmosphere......Page 525
Late Archean atmospheric change......Page 529
Summary......Page 532
References......Page 534
Subject Index......Page 540