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The Solid Earth: an Introduction to Global Geophysics, Second Edition C Cambridge University Press 0521584094 - The Solid Earth: An Introduction to Global Geophysics, Second Edition C. M. R. Fowler Index More information Index absolute age 234 Airy’s hypothesis 203–4, 209, 210, 215, andesitic basalt 397 absolute plate motion 32–6 216, 397 Andrew Bain fracture zone 414 abyssal plain 393, 459, 655, see also ak135 326 angle of shear 621 ocean basin aktualism 595 angular momentum, Earth 348 Acasta gneiss 262 Alaska subduction zone 465 angular velocity 14, 19, 648 accreted terrane 482, 516, 551, 655 Alberta Basin 559, 561, 562, 563, 566 present-day 15 accretion, Earth 265, 285 Alboran Sea 542 relative 18 accretionary wedge, see subduction zone Aleutian subduction zone 6, 77, 461, 465, anisotropy 346–8 accuracy 234 470, 471, 526 oceanic mantle 408 achondritic meteorite, see meteorite Aleutian Trench 8, 86, 475, 477 Antarctica 8, 23, 71, 88 acid rocks 396 alkali basalt, radioactive elements 276 anticline 173, 655 actinium series 247 alkaline rock 397 anticrack faulting, olivine-spinel 472 active margin 394, 655, see also alkali-olivine basalt 397 apatite, closure temperatures 243, 261 continental margin allanite, closure temperatures 243, 261 apatite, fission track 318, 319 activity, see radioactive decay alpha particle 655 Apennines 542 adakite, formation 526 Alpine fault, New Zealand 319 Appalachian Basin 561, 562–5, 566 Adams–Williamson equation 331, 333, Alps 88, 312, 541–50 Appalachians 302, 516, 564 334 crustal thickness 548 Ar–Ar dating, see radioactive dating adiabat 303–7, 334, 343, 350, 524, earthquakes 464 Ar ratio, non-radiogenic atmospheric 254 655 gravity 545, 546 Ar adiabatic expansion 304 seismic structure 546, 547–8, 549 loss 252, 254 Adriatic block 541, 542 seismicity 548 natural isotopic abundance 252 advection 269, 270, 274, 291, 358, 462, shortening 545 radioactive decay 238, 365 see also heat uplift 550 Arabian plate 8, 31, 542 Aegean Altai Shan 535 subduction 526 mantle structure 338 altered rock 655 Arabian Sea, magnetic anomaly 76 relative motion 542 Altyn Tagh Fault 535 Archaean 308, 595–601, 655 subduction zone 344, 461, 541, 542 Amadeus Basin 578 continental crust 280, 596–8 aeon 655 Amazonia 88 diamonds 597 Africa 88 Amitsˆoqgneiss 246 geotherm 598, 600, see also geotherm rifting 585 Amp`ere’s law 617 heat 298, 371, 599 seismic velocity 339 amphibolite 655 initial 87Sr/86Sr ratio 245 Africa–Eurasia, motion, seismicity 440 Amundsen Basin 422 lithosphere 597, 598 African plate 8, 31, 36, 70, 541 Anatolian plate 541, 542 magma anomaly 600 aftershock, see earthquake aftershock Andes 202, 310, 552 magnetic field 381 afterslip, see earthquake afterslip crustal structure 479, 482, 485 mantle 366, 371, 600 age of Earth, see Earth gravity 475, 479 oceanic crust 599, 600 age of Sun 234 Sr ratio 486 plate tectonics 285, 370–1, 599 air gun 141, 157 topography 479 temperature 280, 285 Airy, Sir George 202 andesite 395, 396, 397, 485, 525, 655 Archimedes’ principle 202 666 © Cambridge University Press www.cambridge.org Cambridge University Press 0521584094 - The Solid Earth: An Introduction to Global Geophysics, Second Edition C. M. R. Fowler Index More information Index 667 Arctic 70, 422 seismic velocity 513 boundary-layer model, see plate models arc–trench gap 459 basaltic andesite 397 Boussinesq approximation 355, see also argon, see Ar basement rock 656 convection Arrhenius equation 242 basic rocks 396 Bouvet Triple Junction 8, 33, 71 aseismic region 655 basin 656 bow shock 47 aseismic slip 114, 468, 469, 483 Basin and Range 299, 300, 302, 511, 559, Bowie hotspot 363 Asia, tectonics 535, 536 566, 590 Brazilide Ocean 88 aspect ratio 359–60 Bateman relations 239 breathing mode 110 asteroids, origin 263 batholith 656 British Institutions Reflection Profiling asthenosphere 5, 108, 202, 297, 655 bathymetry 656 Syndicate, see BIRPS viscosity 225, 228 Chain transform fault 443 brittle–ductile transition 514 Atlantic MORB 414 Clipperton transform fault 442 Bruhnes epoch 60 Atlantic Ocean East Pacific Rise 442 Bruhnes, Bernard 60 opening 53, 70, 88, 545 Hawaii 219 BSR, bottom-simulating reflector 167–8, sediment thickness 400 Mid-Atlantic Ridge 392, 411 527 spreading rate 60 mid-ocean ridge 442, 443 bulk Earth, isotope ratio 361 Atlantis Bank 398, 402, 450 New Hebrides Trench 392 bulk modulus 102–4, 331, 332, 625, Atlantis II transform fault, Southwest Pacific–Antarctic Ridge 392 656 Indian Ridge 398, 441, 450, 452 Peru–Chile Trench 392 bulk modulus, versus depth 335 Atlantis transform fault 420–2, 424, 441 Romanche Transform Fault 443 Bullard, Sir Edward (Teddy) 14, 374 atmosphere 47 Southwest Indian Ridge 392 b-value, see earthquake, b-value atomic number 655 St Paul Transform Fault 443 attenuation, see quality factor Bay of Bengal, magnetic anomaly 71, 76 c 126 Aurora 47 Bay of Biscay 542, 574 14C decay 238 Australia 71, 76, 262 Bay of Islands ophiolite 405 Calaveras Fault 124 Australia, gravity 578, 579 b.c.c., see iron calcic rock 397 Australia, rifting from Antarctica 74, Becquerel, Henri 233 Caledonian orogeny 550–1 88 Benioff, Hugo 464 California Australian–Antarctic Discordance 414 beta particle 656 motion 18 auxiliary plane, focal mechanism 134, Betics 542 seismicity 124 137, 139 biotite, closure temperature 243, 261 Cambrian 88 axial magnetization 67 Birch’s law 103, 104 Canada Basin 422 axial volcanic ridge 419 BIRPS 177, 178, 550 Canadian Shield 300, 339 Azores Triple Junction 8, 33, 440 Black Sea 88, 542 Canyon Diablo meteorite 265 black smokers, see hydrothermal Capricorn plate 76 Babylonians 1 circulation carbonaceous chondrite 263 back-arc basin 394, 402, 459, 460, 486, Blake Spur fracture zone 450, 452 Caribbean plate 70 526, 655 Blanco transform fault 441 Carlsberg Ridge 8, 70, 74 backstripping 557 blocking temperature 51, 242, 318, see Carpathians 88, 542 Baffin Bay 70 also closure temperature Cascadia subduction zone 31, 81, 83, Baikal Rift 535, 536, 585 blueschist 523, 656 167, 461 Baja California 82 body wave 101–4, 656 earthquakes 468, 469 balloon mode 110 amplitude 104, 152 heat flow 482 Baltica 88, 302 magnitude, see earthquake seismic structure 168, 483 Banggong Nujiang suture 531, 532 seismic velocity 104 seismic hazard 121 basalt 395, 396, 397, 656 Boltwood, Bruce 233, 262 seismicity 482 melting 518, 526 bottom-simulating reflector, see BSR uplift 473 metamorphic reactions 518 Bouguer anomaly 206, see also gravity Caspian Sea 88, 542 P-wave velocity with P, T 413 Bouguer correction 206 cation 656 radioactive elements 242, 276 Bouguer, Pierre 202 Caucasus 542 © Cambridge University Press www.cambridge.org Cambridge University Press 0521584094 - The Solid Earth: An Introduction to Global Geophysics, Second Edition C. M. R. Fowler Index More information 668 Index CDP reflection method 158, 159, 160, compensation 203, 205, 210, 289, 453, continental heat flow 286, 298–303 162, see also stacking see also isostasy province 299, 300 Cenozoic ocean and continent 204, 209, 397 continental lithosphere, strength envelope Central America subduction zone 465 complementary error function 282 514–15 Central Indian Ridge 8, 70, 71, 74, 75, composition continental margin 418 core 350–3 bathymetry 394 centrifugal acceleration 197 crust 348, 513–17 non-volcanic 568, 570 centripetal acceleration 656 Earth 348–53 passive 393 Chagos–Maldive–Laccadive Ridge 71, mantle 348–50 sediment 398, 560 74, 75 compressional basins 577–81 seismic velocity 576 Chain Transform Fault 443, 458 compressional fault 131 subsidence 575 Challenger Deep 391 compressional wave 656 transform fault 442 Challenger, HMS 391 equation 102 volcanic 568, 569, 576 characteristic distance 281 concordant dates, see radioactive dating continental reconstructions 88 characteristic time 281 concordia, see radioactive dating continental rifting Charlie Gibbs transform fault 452, conduction 5–10, 269, 271, 656, see also Africa and Antarctica 71 see transform fault heat Africa and India 74 chemical remanent magnetization conductive heat flow, timescale 281 Africa and North America 70 51 conductivity, see thermal conductivity Australia and Antarctica 74 chemosynthesis 430 Congo 88 early geometry 443–4 Chile Trench Conrad discontinuity 511 Eurasia and North America 70 bathymetry 479 conservative plate boundary 6 Greenland and Eurasia 70 crustal structure 482 Consortium for Continental Reflection Greenland and North America 70 Chile, composition magma 522 Profiling, see COCORP India and Australia 71 China 88 constructive plate boundary, see divergent Madagascar and Antarctica 71 chondritic meteorite 254, see meteorite boundary continental rifts 70, 124, 570, 584–95 CHUR (chondritic uniform reservoir) contact metamorphism 310 continental rise 393, 394, 656 256–7, 264, 656 continent continental shelf 286, 393, 394, 656 Clapeyron curve, olivine 349, 464 ages 262, 263, 515, 516, 595 continental shield, roots 339, 347 classical ray theory 156 seismic structure 109, 538, 550, 593, continental slope 393, 394, 656 clinopyroxene 349 594 continent–continent collision 75, 362, Clipperton transform fault continental crust 530–55 bathymetry 442 Archaean 597, 598 convection, see also mantle and heat crust 441, 453 area 516, 649 bimodal 354, 355 closed system, see radioactive dating classification 512 Boussinesq approximation 355 closure temperature 242, 243, 244, 252, composition 513–17 cell dimensions 357, 359–60, 365, 366 261, 262 density 10 coupling core and mantle 379 CMB, see core–mantle boundary geotherm 279, 280, 303 critical Rayleigh number 356–7, 358 COCORP 176, 177, 510, 553, 567, 592, heat generation 300–2, 313, 525 dimensionless numbers 356,
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