Author Indexl

Adams, L. H. 58, 186 De Sitter, L. U. 237, 238, 242 Aki, K. 228 Deuker, E. A. 67, 69 Allan, D. W. 55, 58 Deutsch, E. R 61 Anderson, E. M. 221, 243 Dietrich, G. 249 Arrhenius, S. 259 Dobrin, M. B. 259, 260, 261 Du Toit, A. L. 6, 7, 8, 9, 180 Baker, H. B. 6, 7 Baldwin, R B. 251, 252 Eckart, C. 67 Barrell, J. 265 Egyed, L. 11, 205 Barringer, D. M. 24 Elkins, T. A. 241 Basset, A. B. 149 Eotvos, Rv. 119 Beals, C. S. 24 Epstein, P. S. 119 Belousov, V. V. 196, 204, 242 Ertel, H. 119, 120 Bemmelen, H. W. van 196, 198 Escher, B. G. 140 Benioff, H. 39, 40, 41, 106, 108, 109, 111 Ewing, M. 19, 76 Berlage, H. P. 196, 198 Ez, V. V. 242 Bijlaard, P. P. 83, 248 Birch, F. 55, 62, 139, 172 Fairbairn, H. W. 105 Bondi, H. 107 Farquhar, R M. 52, 53, 54 Bowden, F. P. 232 Ferguson, G. M. 24 Bowie, W. 140 Fisher, O. 140 Bridgman, P. W. 105 Brock, B. B. 20 Garland, G. D. 31 Brooks, H. 191 Geszti, J. 247 Bucher, W. H. 143, 167 Gilman, J. J. 99, 100 Bullard, E. C. 56 Goguel, J. 124, 125 Bullen, K. E. 49, 50, 51, 104 Gold, T. 107, 126, 127 Byerly, P. 43 Graham, J. W. 61 Graton, L. C. 263 Carey, S. W. 248 Green, A. E. 69 Chandrasekhar, S. 135, 152, 187 Griffith, A. A. 98, 99 Chen, C. H. 242 Griffiths, D. H. 61 Chertkova, E. I. 242 Griggs, D. 105, 132, 187, 188, 190 Clegg, J. A. 61 Gurevich, G. I. 256 Cloos, E. 256 Gutenberg, B. 28, 29, 32, 35, 36, 37, 38, -,H. 242 39,48,49,50,56,106,108,111,129,142 GzovskiI, M. V. 261 Daly, R. A. 265 Darwin, G. H. 126, 140 Haarmann, E. 141, 196 Davison, C. 153, 166 Hafner, W. 223 De Geer, C. J. 29 Handin, J. 105

1 Slavonic names have been transliterated according to the Cambridge system; this is the system used, for instance, in Physics Abstracts. Author Index 273

Haskell, N. A. 111, 266 Labrouste, H. 49 Havemann, H. 198 Lake, P. 13 Heaps, H. S. 265 Lamb, H. 85, 147, 162, 257 Heezen, B. C. 19 Lambert, W.D. 119, 126 Heim, A. 15 Landau, A. 24 Heiskanen, W. 31 Lebedev, V. 1. 206 Hencky, H. 83 Lee, J. S. 242 Hersey, M. D. 91 -,M. T. 242 Hess, H. H. 191, 192 Lees, G. M. 63 Heywood, W. W. 26 Leutert, W. 154 Hiersemann, L. 35, 36 Lohest, M. 25 Hill, M. J. 20 Love, A. E. H. 74 -, R. 80 Low, A. R. 87 Hills, G. F. S. 144 Lyustikh, E. N. 111, 265 Hirschmann, J. 19 Hobbs, W. H. 20 Malinovskaya, L. N. 231 Hodgson, J. H. 45 Marble, J. P. 4 Holmes, A. 3, 23, 186 Mason, B. 62 Honda, H. 47 Matschinski, M. 155, 192, 205 Hopkins, W. 186 Matuzawa, T. 226 Housner, G. W. 234 McAdams, W. H. 87 Hoyle, F. 136, 138 McDowell, A. N. 261 Hubbert, M. K. 240, 242 Melchior, P. J. 108 Milankovitch, M. 117, 119, 127, 129, 130, Inglis, C. E. 76, 99 131, 208 -, D. R. 125 Milverton, S. W. 87 Mintrop, L. 48 Jacobs, J. A. 56, 57, 58, 139 Mises, R. v. 80 Jaeger, J. C. 74 Mohr, O. 70, 93 Jaggar, T. A. 27 Mollard, J. R. 23 Jardetzky, W. S. 76, 193, 245 Moody, J. D. 20 Jeffreys, H. 74, 86, 106, 107, 110, 116. Mott, N. F. 99 126, 132, 133, 136, 141, 163, 167, Munk, W. H. 126 168 Jobert, G. 132 Nadai, A. 83, 132 Johnston, W. A. 265 Nakano, H. 231 Joksch, H.C. 9,10,157 Nettleton, L. L. 241, 259, 261 Jordan, P. 157 Neumayr, M. 2, 27, 34 Jung, K. 116 Nininger, H. H. 24 Niskanen, E. 265, 270 Kaariiiinen, E. 29 Kalle, K. 249 Kampe de Feriet, J. 184 Oldroyd, J. G. 68, 71, 91 Kawasumi, H. 43 bpik, E. 253 KeIlis-Borok, V. I. 43 Orowan, E. 93, 94, 95, 96, 97, 98, 99 Kogan, S. D. 35, 37 Koppen, W. 4, 5, 9 Pai, S. 184 Kosminskaya, I. P. 49 Pekeris, C. L. 148, 149, 187 Kossinna, E. 9, 10 Pellew, A. 87 Kreichgauer, D. 4, 5 Petch, N. J. 98 Kuenen, P. H. 242 Pirson, L. V. 14 Kuiper, G. P. 136 Press, F. 47, 76 Kukkamaki, T. J. 29 Prey, A. 123 Scheidegger, Principles of Geodynamics 18 274 Author Index

Quiring. H. L. 140 Southwell. R. V. 87 Stille. H. 12 Ramberg. H. 25. 256. 257 Strakhov. N. M. 11 Ramsey. W. H. 62 Suess. F. E. 2. 27. 34 Rankama. K. 61 Reiner. M. 87. 88. 89. 90 Tabor. D. 232 Reuss. A. 81 Terzaghi. K. 112 Richter. C. F. 32. 35. 36. 37. 38. 39. 108 Tiedemann. A. W. 238. 239 Riedel. W. 242 Travis. J. P. 261 Rittmann. A. 264 Truesdell. C. 65. 69 Riznichenko. Yu. V. 49 Tsuboi. C. 32. 33. 56 Roberts. D. K. 100 Turner. F. J. 105 Robertson. E. C. 105 Robinson. R. O. A. 172 Umbgrove. J. H. F. 12. 13 Robson. G. R. 56 Urey. H. C. 152 RotM. J. P. 49 Urry. W. D. 139 Rudnik. P. 107 Runcorn. S. K. 60. 61 Veitsman. P. S. 49 Russell. R. D. 52. 53. 54 Vening Meinesz. F.A. 20. 111.145.189. Rutten. L. M. R. 12 208. 210. 211. 212 Ruud. 1. 165. 247 Verhoogen. J. 56. 57. 263. 264 Vvedenskaya. V. V. 232 Sahama. T. G. 61 Sapper. K. 143 Walker. A. M. 107 Saunders. O. A. 87 Wegener. A. 4. 5. 7. 142. 180. 181 Sauramo. M. 29. 265 Wegmann. C. E. 256 Scheidegger. A. E. 13. 21. 23. 24. 41. 42. Weizsacker. C. F. v. 135 43. 44. 65. 72. 86. 90. 102. 120. 146. Wells. A. A. 100 153. 165. 168. 170. 172. 183. 270 Willmore. P. L. 24. 56 Schmidt. E. R. 208 Wilson. J. T. 13. 15. 16. 17. 18. 19. 52. -.R.J.87 53. 54. 143. 164. 165. 166 Schuchert. C. 15 Woolnough. W. G. 153 Schulz-Weidner. W. 24 Worzel. J. L. 48 Shurbet. G. L. 48 Wylie. C. C. 255 Skerl. J. G. A. 7 Slichter. L. B. 58 Young. A. 107 Smart. W. M. 135 Sonder. R. A. 23. 167. 172 Zardecki see J ardetzky Sorskil. A. A. 258 Zerna. W. 69 Sotome. K. 193 Zoelly. R. 154 Subject Index

Additional stress definition Arctic piercement domes 26 Bulk modulus (incompressi• 72ff. Argon (radiogenic) 52 bility) 74 - - in Earth 223 Arizona crater, origin 253, Buoyancy (of domes) 260 Africa, heat flow 55 255 -, paleoclimate 4 - -, physiography 24, 25 Calcium (radiogenic) 52 -, rift valleys 19, 33, 249 Asia, island arcs 14, 15, 16 California, earthquakes in After-effect (elastic) 89 -, mountain roots in 49 38 Aftershocks (in earth- Atlantic Ocean, heat flow 55 -, mountain roots 49 quakes) 108ff. -, origin of (zonal ro- Canada, heat flow 55 Age, determination 51 tation) 193 -, line patterns 23 -, of geological epochs 4 -, physiography 6, 48 Canadian shield 53f£' Airy function 74 -, ridges 19 Cap range, description 16 Airy hypothesis 31, 49 -, spreading theory 142 -, theory 174, 177 Alaska (mountains) 13 Autocorrelation 184 Carlsberg ridge 19 Aleutians 13, 14, 15, 37 Auxiliary plane 22, 43, 229 Cataclysmic theory of origin Alpine cycle 12 Axis (of fold) 23 of earth 136 Alps, nappes 23 Catastrophe in mountain -, physiography 16 Bands of instability 113 building 12 -, roots 48, 49 Barringer crater (see Ari- Cauchy-Riemann equations -, shortening 15 zona crater) 80 -, speed of formation 162 Basalt, description 63 Chandler wobble 107 Altitude effect (on gravity) -, origin of 144 Circulations, definition 84 30 -, quantity in crust 143 -, on Earth 124ff. America, drift of 184 Basaltic layer 49 Classical bodies 87 -, origin of 194 Batholith 3 ClausiUS-Clapeyron equa- -, paleoclimate 4 BIJLAARD'S theory 113, 213, tion 227 -, westward motion 132, 217, 248 Climate (ancient) 4 184 Bingham solid 90 Coast Range 15, 16 Anatexis 63 Birch discontinuity 50, 62, Cohesion (molecular) 97 ANDERSON'S theory 221 ff., 186, 198, 220 Compatibility condition 67 243 Boudinage, description 25 ff. Competent layer 25, 256ff. Andes 14, 16 -, theory 256f£' Compressional waves, de- Andesite, description 63 Bouguer anomaly 31 finition 33 -, origin 144 Branch point line 165, 247 -, see also P waves -, quantity in crust 143 Brasil, paleoclimate 4 Concentric folding 237ff. -, line 63 Britain, heat flow 55 Congo: volcanoes 28 Anomalies (gravity) 30 British Columbia, mountain Conrad discontinuity 49 Antarctica (uplift) 265 ranges 13 Conservation of phase signs Anticline 23 Brittleness 93 42 Appalachian cycle 12 -, in notches 94 Constitutive equations 71 Appalachians 15 -, see also fracture, brittle Continental drift, concept Archean rocks 53, 258 Buckling, description 79 6ff. Arcs (mountain and island) -, in orogenesis 175, 205, -, magnetic evidence 61 35 (see also orogenesis) 236 -, theory 141 ff., 179ff. 18* 276 Subject Index

Continents, crustal studies Damping of oscillations 89 Elastic constants of Earth 47 Dating, paleontological 3 104ff. -, dynamics 134ff. Dating, radioactive 51 ff Elastic limit 80 -, geography 6 Deep earthquakes 35 Elasticity theory 73 ft. -, growth theory 53ff., Deflections 16 Ellipticity of Earth 116 143ff., 166 Deformation, description 65 Energy of earthquake -, margin 33 -, measure 65 38ff. -, nucleus 53 -, mechanics 64ff. Epicenter 33 -, spreading 142 Density, definition 67 Equation of motion 69 Continuity condition 68ff. -, Earth 30, 50ff. Europe: paleoclimate 4 Continuous media 64 Depth of focus 35 Evolution (geological) 2 Contraction theory 144, Detrition 3 Expansion theory 154, 162ff. Deviator (of a tensor) 81 204ff. Contraction theory (tetra- Dextral fault 22 Extension factor 160, 161, hedral) 153 Differentiation of magma 177ff., 182, 207, 219 Convected coordinates 68 198 ff. Convection currents, con- Dip (of fault) 21 tinental 145 Discontinuities (mathe- Failure (of materials) 93££. -, magnetic field 59 matical) 92ff., 101 Fatigue 95 -,orogenetic 144ff., Discontinuity, Birch 50, 62, Fault, description 21 185, 186ff. 186, 198, 220 -, dynamics 221 ff. -, plastic 90 -, Conrad 49 -, scale models 241 -, thermal theory 86, -, core 49 Fault plane studies 41 ff., 87 -, Mohorovicic 32, 47ff., 229 Convection cycle 189ff. 49, 63, 105 Fennoscandia, gravity 32, Cooling (of Earth) 3, 58 Dislocation 79, 102, 225, 33 Coordinate space 65 234ff. -, uplift 29, 111, 265 Core, chemistry 62 Dispersion (surface waves) Field theory (of earth- -, electrical conductivity 48 quakes) 226 62 Domes, physiography 25 Figure (of Earth) 116ff. -, seismic velocities 50 -, theory of formation Finite strain 64, 65ff. -, inner 50 259ff. First rocks 3 Coriolis forces 132ff. Ductility 94 Focal sphere 41 ff., 228ff. Correlation coefficient 184 Dunite 62 Focus (of earthquake), de- COULOMB'S hypothesis 93 Dust: interstellar 135 finition 33 ff. Craters, meteoritic 24, Dyke 22, 222 -, mechanism 41, 228ff. 251ff. Folds, description 23 -, on Moon 165, 197, -, dynamics 235 247 Earthquakes, description -, scale models 242 -, volcanic 27 33ff. -, systems 245 Creep 88, 165 -, energy 38 Foredeep 15 Creep fracture 96 -, fault plane studies Fossils 3 Crustal shortening 14, 41 ff. Fossil craters 24 159ff. -, field theory 266 Fossil ice 5 Crust, chemistry 62 -, magnitude 37ff. Fourier equation 58 -, extension factor 161 -, mechanism 106 Fracture, analytical theo- -, layering 47 -, strain release 39ff. ries 101 ff. -,strength 105,112,115 -, theory 225ff. -, brittle 93 Curvature tensor 67, 73 -, waves 49 -, criteria 92ff., 99 Cycle, convection theory Eclogite 62 -, cup-and-cone 94 190 Eigenvalues (in buckling) -, ductile 94 -, geochemical 63 237 -, in Earth 221 -, orogenetic 12, 55 Elastic buckling 236 -,in earthquakes 233 ff. Subject Index 277

Fracture, fatigue 95 Haskell theory 266 Keewatin 53 -, fault systems 243 Hawaii: volcanoes 27 Kelvin constants, definition -, fibrous 94 Heat flow 55 89 -, GRIFFITH'S theory 98ff. Hinge line 21 - -, in Earth 115, 270 -, intergranular 96, 234 HOOKE'S law 74 Kelvin solid 88 ff. -, microscopic theories Hypsometric curve, de- Kodiak 15 97ff. scription 9 ff. Krakatau 27 -, principles 92ff. - -, explanation 157 Kuriles 13, is, 37 -, shear- 94 Free-air anomaly 31 Friction: in earthquakes 232 Ice ages 6, 32 Lame constants 74 Front range 177 Iceland: uplift 265 Laminar flow 85 Igneous rocks 2 Laurasia 7, 8, 141, 180 Gal (unit) 30 Incompetent layer 256ff. Lava, amount in crust Ganges Valley: sediments India, drift of 61, 184 143 12 -, gravity 33 -, description 2, 63 -, viscosity 264 Geocentric latitude 116 -, uplift 265 Geochemistry 61 ff. Indian Ocean 19, 48 -, volume 263 Geodepression 197 Indonesia 45 Lead (radiogenic) 52 Geological time scale 3 Inglis solution 76 Lenses (tectonic) 258 - - - extended 52 Inner core 50 Level of no strain 45, 163, Geophysical data 30ff. Intensity (of fold) 23 167ff. Geosyncline 12, 20, 48, 159, Interior (of Earth) 49 Limb (of fold) 23 165, 166, 246 -, chemistry 61 Lineaments 16, 17, 174, Geotumor 197 -, density 51 245 Glaciation 4, 6 -, temperature 56 Lines (patterns of) 21 Gliding (by gravity) 203 -, wave velocity 50 Linkage, description 16 Gondwanaland 7, 8, 141, Intermediate earthquakes -, explanation 174 180 35 Logarithmico-normal di- Granite 2, 63 Intermediate layer 49 stribution 10 Granitic layer 49 Intermediate time inter• Long time intervals, defi• Granodiorite 2, 63 vals, defini• nition 103 Grashoff number 86, 91, tion 103 - - -, rheology 1lOff. 188 -, rheology 107ff. L-phase 33 Gravitation, variation of International gravity for• mula 30 constant 157 Magma; differentiation 144, Isachsen dome 27 Gravity 30ff. 198ff. Island arcs, contraction Gravity anomaly, Bouguer -, viscosity 200 . theory 163 31 'Magnetic field, secftlar -, drift theory 180 - -, free-air 31 variation 59 -, gravity 32 - -, isostatic 31 - -, westward drift 59 -, physiography 11 ff. Gravity field 30 Magnetization, polar wan- Isostasy 31, 48, 265 Gravity formula (inter- dering 60 Isostatic anomaly 31 national) 30 -, principles 59ff. Grenville 53 -, reversal 61 Griffith theory, principles James Bay: uplift 53 Magneto-hydrodynamics 59 98 Japan 13, 37 Magnitude of earthquakes, - -, in earthquakes 234 Joints 22, 223, 245 connection Group velocity 76 Jump vector 101 with slip Gulf of Bothnia: uplift Junctions of arcs, physio- 235 29 graphy 16 -, definition 37ff. Gulf of St. Lawrence: origin - - -, theory 172 -, Richter 37 24 Jupiter 137 -, teleseismic 38,39 278 Subject Index

Magnitude of earthquakes, Moment of inertia: of Earth Pakistan: lineaments 23 unified 38, 39 124 Paleobiology 9 Mantle, chemistry 62 Moon, craters 165, 197,203, Paleoclimatic data 4, 61 -, strength 106 247, 250ff. Paleomagnetism 59ff. -, thermicity 58 -, origin 140, 141 Paleozoic cycle 12 -, rigidity 107 Mountain building see Paleozoic mountains 18 -, viscosity 108, 111 orogenesis Pamir 45 Margin of continents 33 Mountain ranges 11 ff., Parameter space 65 Mariana Islands 37 13ff. Peridotite 62 Marsupalia 9 Mountain roots 31, 48ff. Phase 33 Material form: equations Phase-discontinuity 63 of motion 65 Phase velocity 76 Maxwell constants, defini- Navier-Stokes equation 85 Philippines 13, 16 tion 88 Nebula (stellar) 135 Physiography (of Earth) - -, in Earth 115 Necking: plastic 83 1 ff. Maxwell liquid 88 New Quebec Crater 24 Piercement domes 26 Medianland 17 Newtonian fluids see vis- Pinch-and-swell structures Mega cells 191 cous fluids 25, 257 Melanesia 16 New Zealand: uplift 265 Pitch (of fold) 23 Metamorphism 3, 63, 161, Nodal lines: in seismology Plane strain state 75, 82 206 229 Plane stress state 75 Metamorphosis factor 161, Normal fault 22, 222 Planets 134ff. 178 North America, mountains Plasticity, theory 80ff. Meteor craters 24, 250ff. 19 -, in folding 247 Meteorites 250ff. -, paleoclimate 4 -, in convection 91, 189 Mexico 13 -, uplift 265 POISSON'S ratio 74 Micronesia 45 -, westward drift 132 Polar wandering, magnetic Mid-Atlantic Ridge 19, Notch brittleness 94 evidence 60 249 Novaya Zemlya: uplift 265 -, paleoclimatic evid• Mid-Atlantic Rift 19, ence 4ff. 249 -, tectonic effects Mid-ocean ridges; origin Oceans, area 47 217ff. 144, 249 -, composition of bottom -, theory of 124ff., -. -, physiography 19 ~ ~7~ - -, seismicity 33 -, geodynamics of 134ff. Polfluchtkraft, concept and Milankovitch theorem -, geography 6 theory 119ff. 129 -, trenches 48, 49 -, criticisms 123ff. Models, boudinage 256ff. Origin of Earth 53, 134 -, orogenetic effects 142 -, domes 260 Orogenesis 11 ff., 53, 55, Potassium-40 (decay) 52 -, faults, folds etc. 240, 159ff. Prandtl number 86, 91, 241 ff. Orogenetic cycle 13, 55 188 -, theoretical: of earth• Orogenetic systems 11 ff., Pratt hypothesis 31, 49 quake foci 228ff. 1 59, 167 Precambrian type folding -, theory of scale models Oscillation damping 89 52ff., 171, 245 240ff. Principal stress 70 Mohorovici6 discontinuity Proterozoic 53 32, 47ff., 49, 63, 105 Pacific Ocean, composition Pseudoviscosity 189 Mohr circle 70 of bottom 63, 142 P waves 33, 76 Mohr theory, earthquakes -, geography 6 234 -, heat flow 55 -, exposition 93 -, origin 140 Radioactivity and age de• -, faulting 221 -, ridges 19 terminations 51 ff. -, rocks 105 -, trenches 48 - and heat flow 56, 58 Subject Index 279

RAMSEY'S hypothesis 62 Seismogram 33. 49 Stress. definition 69 Rays (seismic) 33 Seismograph 33 -. in Earth: Build-up Recent mountains 17 Seismology 33 ff. 226 Relaxation of stress 88 -. and contraction theory -, in Earth: Due to polar Reversal of magnetization 178 wandering 211 ff. 61 Seymour Islands 6 Stress function 74, 223 Reversed arcs 19. 177 Shallow earthquakes 35 Stress tensor 69 Reversed fault. definition 22 Shear 69 Strike (of fault) 21 - -. explanation 222 Shearing plane in folds Strontium (radiogenic) 52 Reynolds number 85. 86 239 Summation convention 65 Rhegmagenesis 23 Shear patterns 20 Sun 134ff. Rheidity 248 Shear waves 76 Supernova 136 Rheological condition. de- Shield 6. 53. 144 Surface energy 97 finition 71 Shortening see crustal Surface waves 33. 48. 76 - -, crust of Earth 210 shortening S waves 76 - -, Earth 102££. Short time intervals. defi- Syncline 23 Rheology. principles 64ff.. nition 103 Systems of faults and folds 87 -- -, rheology 104ff. 243 -. of Earth 102 ff. Shrinkage see contraction Systems of mountain ranges Richter magnitude 38 Sial 198 15 Riemann-Christoffel tensor Siberia 4 67. 73 Sierra Nevada, physiogra- Rift systems 249 phy 16 Tectogene 12.48. 159, 166, Rift valleys 19 - -, roots 48 187, 201 Rigidity. definition 74 Sima 198 Tectonic lenses 258 -, of Earth 115 Sinistral fault 22 Temperature (in Earth) -. of mantle 107 Sliding (by gravity) 203 56ff. Riu Kiu arc 13. 15 Slip: in earthquakes 234ff. Tensile strength 93 Rocks 2 Slip angle 21. 22 Tension 69 Rocky mountains. physio• Slip lines 82ff.. 165 Terzaghi equation 112. graphy 15 Solar system 134 ff. 262 - -, speed of formation South Sandwich Islands 1 5 Tessera 20 162 Spatial form (of equations Tethys geosyncline 8 Roller cells 191. 192 of motion) 66 Thermal data 55 Roots (of mountains) 31. S phase 33 Thermal history of Earth 48ff. Spitzbergen: uplift 265 55. 57. 137ff. Rotation (of Earth). de- Splay faulting 244 Thermohydrodynamics 86 scription 116 ff. Standard stress 72. 223 Thixotropy 1 13 -. orogenesis 206ff. STOKES' law (for falling Thorium: decay 52 -, zonal 192ff. sphere) 86 Thrust fault, description Rubidium (decay) 51 STOKES' theorem 84 22 Strain 64ff., 66 -, explanation 222 Strain energy 97 Tidal forces 131ff. Salt domes 259 Strain-hardening 81 Tidal friction 110, 132 Samfrau geosyncline 8 Strain rebound theory Tides in Sun 136 Scaling 240 226 -, causing separation of Scorpionidae 9 Strain release 39ff. Moon 140 Scum theory 145 Stratification 3 Time scale (geological) 3 Sea level 10 Strength of ash 262 Timor 15 Sedimentary rocks 2. 63 of crust 105, 112 Traction 69 Sedimentation 3. 63 of granite 106 Transcurrent fault. defini• Seismicity 35 ff. of mantle 106 tion 22 Seismic waves 33ff. of materials 97, 106 - -, explanation 222 280 Subject Index.

Travel-time curves 33, 49 Velocity of crack propaga- Vortex tube 84 Transverse waves 33 tion 99ff. Vorticity 84 Trinidad 15 - of seismic waves 49, 104, Turbulence 85, 91, 260 105 Wandering of pole see polar Venezuela: lineaments 23 wandering Undations 11 Vesuvius 27 Water (quantity on Earth) 11 Undation theory 144, 196 Viscosity, definition 84 Waves (earthquakes) 49, 75 Unified magnitude 38 -, in Earth 115, 270 West Indies 14, 19, 24 Uniformitarian theory of -, of magma 200 origin of Earth 135 -, of mantle 108, 111 Yielding 80 United States, heat flow 55 Viscous fluids 84 ff. YOUNG'S modulus 74 - -, mountains 13, 19 Volcanism 27, 143, 262ff. Uplift (postglacial) 29, 111, Volcanoes, description 27 Zero strain 66, 72 265ff. -, dynamics 262ff. - stress 73 Uranium (decay) 52 -, heat flow 56 Zonal rotation 192ff.