Subject Index

Note: page references in italic refer to figures, those in bold to tables.

A-type granitoids 152 not applicable to Archaean 227 Aachen-Nohes Venn thrust, reflection line across 2, 3 revisited 174-5 Abitibi greenstone belt 180 andesite-rhyodacite 183 abundances, granulite suites 279, 280--I andesites 149, 222 accretion 218, 225 calc-alkaline 247 continental, late Archaean 305 circum-Pacific volcanic areas 222 lateral 222, 228 modern, depth of melting defined 188 of Nfik 257 andesitic crustal composition 147, 148 Suomussalmi gneisses 215 Andrade's law 113 tectonic 372 anorogenic igneous intrusion 110 accretionary prisms 69 anorthosite 24, 76, 197, 224, 232, 239 acoustic contrast 114 apatite 242, 264 acoustic impedance 17 aqueous fluid, solute-rich 154 defined 18 Aravalli-Delhi orogenic belt, N. 226 'Urach body' 125 arc axis 149, 150 actinolite 336 arc basement 150 adiabat, upper mantle 66-7 arc boninites 72, 150 Adirondack Mountains 24, 101-2 arc crust, state of stress 151 adsorption 96 arc generation 72 advection 68, 109 arc-marginal basin system 222 agmatites 95, 99 arc-trench gap 224 airgun arrays 11 Archaean crust A1 309 bimodal suite 174 albite 337 bulk composition of 173 Aleutian arc 149, 150, 153 chemical composition of 173-7 alkali enrichment 270 vertical differentiation 177 allanite 264, 267 vertically zoned 227 almandine 183, 336 Archaean foreland 51, 53 Alpine orogeny 119, 201 Archaean sedimentary rocks new shear motion pattern 120 coherence between REE and Th 176 alteration, late stage 336, 337 geochemistry of 173-7 Amadeus Basin andesite model revisited 174-5 central Australian basins 143 Archaean upper crust 176 sediment accumulation 134 constraints from heat flow 175-6 oil wells, geothermal gradients 136 Eu enrichment, trondhjemites and the lower crust Ambenali 359 177 Am~tsoq gneisses, W Greenland 214, 215, 251,252, 267 geochemical distribution and differentiation of the age and isotope data 253, 254, 256, 257 Archaean crust 177 derivation of 257 total crust composition 176-7 Rb-Sr analytical data 254 recycling model 176 amphibole 287 Archaean sediments, synorogenic origin 176 inhibiting migration 59 Archaean shales, trace element geochemistry 176 tschermakite component in 292, 294 Archaean tonalitic-trondhjemitic rocks, amphibole- thermometer 343 geochemical constraints on origin of 179-89 56, 148, 165, 183, 224, 231,331 Archaean total crust compositions 176-7 dehydration of 154 Archaean upper crustal compositions 176 source 183-4 Archie's law conductivity 56, 154 amphibolite facies assemblages 203, 286 arcs amphibolite facies overprint, retrograde 315 Aleutian 149, 150, 153 amphibolite facies rocks 98 Andean-type, plutonic 225 amphibolite-granulite boundary 261 continental, root zone 151 amphibolite/granulite transition 263 inner and outer, pressure gradient between 102-3 CO2 abundance 165 island 51,225, 226 prograde 165, 167, 168-9 coalescence of 305 anatectic melting 203 collage of 225 anatectic melts, lower crust 170 magmatic 149 anatexis 33, 165, 251,276, 284, 286, 288, 293, 294, 299 oceanic 149 crustal I 1 I, 216, 258 volcanic 71 Andes 222 accreted 305 andesite model 149, 151,280 arcuate crossing events 24, 25, 31, 32

375 376 Subject Index arcuate events BIRPS (British Institutions' Reflection Profiling Syndi- complex 25 cate) 11 complex, Wind River Mountains 23 BIRPS profiles 12, 46 Ivrea Zone 30 Flannan and Outer Isles 72 aseismic ridges 225 BIRPS record, typical 11-17 assemblages reflections from the lower crust 15-17 equilibration of 363 selected line drawings 12-15 high-P, age of 201 blastomylonites 100 assimilation during emplacement 247 blob geometry 72 augen gneisses 223 upper crust 76 aulacogens 222-3 blueschist facies 199 blueschist-facies assemblages 198 blueschists 201,224 Ba 181,240, 241,242, 244, 358 Bohemian Massif 102 back-arc basins 224, 226 brachyanticlinal structures 10I Badcall Quay Red , U-enrichment 216-17 brines 154 Balmuccia peridotite 232 deep crustal 56 Balmuccia/LLG contact 233 in metasedimentary lithologies 165 Baltic Shield, crustal evolution 283 Na-CI bearing 165, 169 basalt 155 brittle crust I01, 103 alkali 351 brittle deformation 72, 76, 83, 84, 86, 98, 99 flood, continental 358 brittle failure 82, 83, 141 high-A1, and new arc composition 149 upper crust 84 pillowed, tholeiitic 226 brittle faulting 108, 112-13 Tertiary, Queensland, Australia 305 brittle fracturing 99 basin evolution sequences 141 brittle strength 79 basin sediments, central Australia 137 brittle-ductile transition 88, 89 basin stratigraphy, on-lap and off-lap 91 depth of 79 basins depth determined by geothermal gradient 92, 95 back-arc 224 and lateral changes in physical properties 129 Caithness 13 movement of 129 Dalradian 52, 60 raised by heat 151 Minch 11, 13 brute stacks 16 North Celtic Sea 15 bulk assimilation process 246 St George's Channel 15 bulk mixing models 246 sedimentary 51 buoyancy differential 259 Mesozoic 12, 13 buoyancy effects 177 post Permo-Triassic 15 buoyancy forces 102, 138 post-Carboniferous 11 buoyant rebound 305 Vale of Eden 11 buoyant uplift 204 volcano-sedimentary 222 burial 69 West Orkney 13 burial metamorphism 112 batch melting calculations, parameters used 184 Byerlee's relationship 6 batholiths Andean 228 Ca 269, 309 Andean type 221,226 Cabo de Gata, Spain 322 circum-Pacific belts 222 Cadomian orogenic cycle 203 Coast Range, British Columbia 225 Caledonian orogeny 197, 201 Gangdese 224 Caledonides 13, 14, 60, 204 Kohistan, N. Pakistan 225 American 51 Palaeozoic, Chile 222 Norwegian 195, 201 Patagonian 222 California, Gulf of 74 deformed metasediments in root zones 227 Canadian Precambrian shield, estimated surface com- Bavarian Molasse trough, crustal reflection line I position 276 Belomorian fold belt 283 carbonate rocks, and the source of CO2 170 Biligirirangan Hills 299, 300 carbonate-clastic sedimentary sequence 223 , 239, 240, 241,265, 288, 298, 302, 337 carbonates 170 re-equilibration of 291 carbonatite 171 secondary 336 carbonatite-like melts 170 biotite fractionation 246 carbonic fluid inclusions 161 biotite 305 carbonic fluids, source of 305 biotite (sillimanite) gneisses 337, 340 Carpathian anomaly 42 Biot's equation 101 cataclastic deformation 114, 115, 116 Birch law 133 cataclastic flow ! 12-13, 114 Subject Index 377 cation diffusion in minerals 316 contact heating 310 Ce 235, 242, 322 contamination central Australian basin, predicted N-S cross-section by bulk assimilation 245 142 by continental crust 246 Central Metasedimentary Belt, Canada 225-6 mixing with silicic partial melts 245 CH4 154, 164, 165, 167 contamination hypothesis assessed 245-7 charnockite-khondalite massif 298, 300-3 continental collision 284 charnockites 298, 299, 305 continental crust retrogression of 301 Archaean 283 charnockites and gneisses, S. India and Sri Lanka, average composition, andesitic 147 analyses of 300 contamination by 246 'charnockitic gneisses' 170, 171 diversity of thermal states 66 chemical fractionation processes 327 generation of 222 chemical zoning profiles 195, 202, 203 growth of, magmatic 227 chert 224 heterogeneous 75, 110 clastic sedimentation and tectonic uplift 176 lower clinopyroxene 187, 197, 287, 292, 336 electrical resistivity in 35-46 Closepet Granite 297, 298 geophysical features of 107-8 CO2 164, 165, 167 heat and tectonics in formation of 107 dominant fluid in granulites 169 normal resistivity in inactive regions 35-41 liquid, inclusions 154 zone of low viscosity 7 origin of 169-71 nature of 46 CO2 density 167 rheologically weak 7 CO2 inclusions 60 stabilization of 110 CO2-rich fluids 227, 293, 294, 299 thermal gradients in 63-9 CO2-rich solution flux, deformation controlled 302 timing and evolution of 214 CO2-rich vapours 299 upper, composition of 277 COCORP 23 continental heat flow 67, 175 COCORP data 223 continental lithosphere 228 COCORP profiles intraplate 86 Adirondacks 24, 25 continental lithosphere strength: critical role of lower Hardeman County, Texas 25, 27, 29 crustal deformation 79-92 Kansas 24, 26, 29-30, 32 continental nucleii, generation and coalescence of 276 Kettle Dome, Washington 27 continental orogenic zones 173 Laramie Range, Wyoming 27 continental plateaux 225 Long Island 25, 29, 32 continental plates Minnesota 23, 24, 32 collision of 203-4 Nevada 27 underthrusting 196, 199 Rio Grande Rift 26 continental rifting 109 Ruby Mountains 27, 32 continental rise 223 Southern Appalachians 27 continental shields, stable 87 Wind River Mountains 23-4, 72 continental stabilization, Proterozoic 109 collision belts, complex make-up 228 continuous profiling technique 1 collision processes 110 convection collision zones 109, 114 of the earth 228 collisional orogenic belts 225, 283 mantle 108, 109 Phanerozoic 222-5 convective processes and surface heat loss 109 Colorado Delta 74 cordierite 288, 293 Colorado Plateau 155 cordilleran belts xenoliths in diatremes 331-47 Andean type 221-2 compaction 100, 113 magmatic 225 compaction disequilibria 96 Cr 174, 175, 235, 239, 244, 312 competent elastic core 86 crack porosity and seismic velocity variations 59 competent elastic lithosphere 79 crack-sealing 98 compositional layering 336 cracks compression 225, 284 cleavage 56 compressional deformation 87 flat 56 compressional tectonics 4 fluid-filled 18, 76 compressive forces, central Australian basins 133, 140, grain-boundary 56 143 sealed 57 conductivity 154 transangular 56 confining pressure 71,111, 112 cratonic areas 276 Lewisian metamorphic rocks 56 stable 351 Conrad discontinuity 65, 71, 76, 103, 104 cratonic margin, Lesotho 356 378 Subject Index cratonization, central Australian region 133 crustal material, subduction to depth 224 creep 113 crustal melting 154 ductile 83 structural cause 153 in lower crust 140 crustal modification 74-5 creep laws 6 crustal protoliths 203 creep release of stress 119 crustal radioactivity 66, 67 creep stress high, steady-state 102 crustal recycling 150, 151 crust crustal reflection properties 147 Archaean, vertical stratification of, S. India 303 crustal reflectivity patterns, latest tectonic event 9 attenuated 32 crustal reflectors 25 brittle 101,103 nature of 7, 9 crystalline, deformation of 27 crustal residence ages 215, 218, 313 deep records from airguns 11 crustal residence time 257 deep, P-T conditions in 218 pre-metamorphic 211 ductility, length of 227 crustal rheology 92 granulite, U-depleted 216 petrological aspects of 95 lower, horizontal reflections from 18-19 crustal rocks, resistivity 35 mafic 188 crustal seismic velocity 147 newly added, identification of composition 151 crustal shortening 74, 103, 195, 204, 305 not in isostatic equilibrium, central Australia 133, eventual nature of lower crust 75 138 and large-scale fold structures 101 solidification of 275 crustal stabilization 227, 351 tectonism and tectonic style of 109 crustal strength, influenced by metamorphism I 11 thermally young, and crustal seismicity 112 crustal stress tensors 127 upper, stretching of 11 crustal stretching 228 young, generation of 5 crustal structure 226-7 crust building models 305-6 central Australian basins 137-8 crust estimate, Proterozoic 278, 279 crustal structure and evolution: central crust material, generation of 128, 278 Australian basins 133-43 crust-mantle boundary 51, 52, 103, 358 crustal structure 137-8 crust-mantle decoupling, role of Moho 92 geological setting 133-4 crust-mantle differentiation 214, 309 geophysical observations 135-6 timing of 215 state of stress 138-40 crust-mantle interface 199 tectonic evolution 140-3 crust-mantle transition 309, 372 crustal structure, Hohenzollern Graben region 121, 125 crustal accretion events 257 crustal thermal conditions 193 crustal accretion mechanisms 21 4-15 crustal thickening 74, 113, 203, 323, 328 crustal age 115 collision zones 195 crustal anatexis 111,258 crustal thickness crustal assimilation 150, 246 control on flexural rigidity 91 crustal blocks, S. India 304-5 and crustal rheology 90 crustal component contamination 237, 243 influencing deep lithosphere temperature 68 crustal composition, geophysical and physical con- and vertical distribution of stress 89 straints 175 crustal thinning 17, 113 crustal contamination 246, 247 crustal tilting 204 crustal contamination processes 359 crustal types 73 crustal cooling 275 Archaean 72 crustal delamination 156 crustal underplating 32 crustal density 53 crustal viscosities and seismicity 6-7 crustal differentiation 75 crystal fractionation 149 crustal evolution 173 mafic magma 181, 183 crustal fusion 151,153 mechanism of 153 thermal problem 154 crystal plasticity 100, 113 crustal generation 72-4, 227 crystalline rocks Archaean 228 permeability 96 crustal growth porosities at low confining pressures 56 during the Phanerozoic 173 crystallization seams 5 Ivrea zone 247 and tamellae 7 and primary compositions 149 crystallization, igneous 313 crustal heating 68, 153-4 Cs 181,268 crustal imbrication, Baltic foreland 198 cumulates 235, 244, 312, 359, 365, 369 crustal inhomogeneity 72 anorthositic gabbro 222 crustal intrusives, composition of 149 gabbroic 358 crustal magma chamber 247 igneous 365 Subject Index 379

lower layered group 239 detachment horizons 86 cumulus apatite 241 deviatoric stress 100, 112-13, 114 cumulus ilmenite 241 dewatering 57, 96 cumulus magnetite 241 dewatering processes 98 cumulus mineralogy 239 dewatering reactions 98 diagenesis 96, 113 dacite 152 diamonds 352 Dalradian Basin 52, 60 diapiric upwelling 315 decarbonation reactions 155 diatexites 286, 288, 291 d6collement 98, 99, 223 diatexitic texture 320 d6collement horizons 103 diatreme eruptions 331,345 decompression 199 diatremes 345 decoupling 188 differentiation 76 deep crust by crustal warming 75 Archaean 226-7 crust-mantle 218 origin of metasediments 227 igneous 150 records from airgun arrays 11 secondary I08 deep crustal reflecting wedge 46 Suomussalmi gneisses 215 deep crustal reflectors 27 diffraction patterns, Urach profiles 2, 4 deep seismic profiling, Germany 1-9 dilatancy 112 deformation 96, 104, 141,143, 197, 203,223-4, 226,227, dilatancy hardening 100, 112, 113 228, 233,263, 284, 294 dilatancy pumping 100 Archaean, Saglek-Hebron 262 diorite 222, 232, 239, 241 brittle 72, 76, 83, 84, 86, 98, 99 disaggregation 100 by creep 72 dislocation creep by thrusting 223 mechanism 80 cataclastic 113, 116 wet quartz 82 central Australian basins 134 domains collisional 224 gneiss and granulite 227 compressional, heat flow required 87 granite-gneisses-greenstone 283 distributed 112 dome and basin structure 304 dome-synform phase 254 domes 251,259 ductile 72, 98, 226 Dorn law creep, olivine 82 control on lithosphere strength 84, 92 dry melting 66, 67 controlled by temperature 86 ductile creep 83 during orogenic shortening 101 ductile deep crust 32 experimental, partially melted granite 99-100 ductile deformation 3 l, 72, 82, 98, 226 following early hydration 345 control on lithosphere strength 84, 92 heat and thermal processes 107-16 controlled by temperature 86 horizontal 82 lower crust, plagioctase-controlled 80 orogenic 110 mantle, olivine-controlled 80 polyphase 165, 168-9 upper crust, quartz-controlled 80 post-collisional, N. Pakistan 223 ductile extension 33, 74 prograde metamorphic conditions 99 ductile flow 26 Saxony 'core' granulites 100 ductile high strain zone 226 tectonic 88 ductile lithosphere deformation 79-80, 81 deformation mechanisms 102, 104 ductile regime 7 deformation processes 115 ductile shear belts 226 dehydration 110, 112, 113, 299 ductile shear zone 223 of granulite facies 254 ductile strain, mid-crustal 76 of subducted plates 110 ductile strength 79, 82 dehydration reactions 57, 108 ductility metamorphic 108 of lower crust 15, 19 sources of water 44 reaction enhanced 98 delamination 74, 75, 76 and temperature increase at depth 110 Delegate Pipe, E. Australia 66 dunites 224 density effects 177 dyke injection 68 denudation 75, 76 dykes depleted mantle evolution path 312, 313 basic 223, 258 depleted mantle field 246 diabase, Matachewan 278 depletion, superimposed 261 gabbro and pyroxenite 239 desiccating fluid phase 154 minette 331 detachment 45 Proterozoic 263 detachment fault 27 Saglek 262 380 Subject Index dykes (cont.) in kimberlite 355 swarms 109 equilibrium liquid composition 239 basic 222 equilibrium melting 183 equilibrium textures, primary 323 erosion 113,222, 305 early hydration assemblages 337 fluvio/glacial 198 earthquake hypocentres, regions of known heat flow 88 Eu 187, 235 earthquakes 119 Eu abundance 357 depth-frequency distribution of 6-7, 8 Eu anomalies 173, 183, 184, 187,235,240,242,267,311, Hohenzollern Graben region, fault plane solutions of 312, 322, 358 125 Eu enrichment 177 eastern Australia, crustal development 371 exhumation, rate of 204 echo-time to Moho 11, 13, 15 exsolution 203, 365 eclogite facies 286 exsolution textures 199 eclogite facies assemblages 193, 203 extension 27, 32, 33, 225, 228 high-P/medium-T 197 ductile 74 eclogite facies metamorphism in the lower crust 193- extensional tectonics 1, 5 205 high-P metamorphism fabric anisotropy 100, 101 European Variscan fold belt 201,203 Faille du Midi fault see Aachen-Nohes Venn thrust Sesia-Lanzo zone, Western Alps 199, 201 fault Western Gneiss region, Norwegian Caledonides fault reflection, Variscan Front 15 195-9 fault zones 51 tectono-thermal model, eclogite formation in conti- good reflectors 7 nental crust 195, 196 origin from a strain-softening process 115 eclogite formation 201 as reflectors 9 eclogite (high-P)/blueschist-facies 199 faulting 113 eclogite lenses 197 brittle 108, I I2 13 eclogite (medium-T)/high-P granulite association 201 faults 110 eclogite source 187 Flannan Fault 14, 51 eclogite stabilization 204 Great Glen Fault 14 eclogites 102, 183, 224, 226, 363, 368, 369 Handy 263, 264, 269 blueschist-facies terrains 193 inferred 12 medium-T 195, 197, 201,203, 204-5 listric 1, 33 pressure estimates difficult 343 listric normal 51 temperatures obtained 343 normal 12, 15 zoning in 346 normal, low-angle 13, 15, 19 eclogites in diatremes 346 Mesozoic 17 Eclogitic Micaschist complex (EMS), Sesia-Lanzo zone Outer Hebrides Fault 15 199 Outer Hebrides fault zone 13, 14 effective relaxation time 140 overthrusts 4 effective stress 56 reactivated 12, 18 elastic flexural thickness, effective, of the lithosphere 90 strike-slip, post-accretion 225 elastic-ductile transition 84, 91 thrust 2, 17, 19 electrical conductivity 35, 56, 60, 115 transverse 15 high Fe 269 causes of 42, 71 Fe-Mg partitioning 343 deep crustal zones of 154 Fe-Mg system, extended 287, 288 zones of 107 feldspar 102, 288, 337 lower continental crust 18-19 feldspar blastesis 258 lower crust 55 Fennoscandian Shield 109 and saline fluid inclusions 59 Flannan fault (Flannan Thrust) 14, 51 electrical conductivity anomalies 155 flexural rigidity 90, 91, 92, 113 electrical resistivity in continental lower crust 35-46 controlled by lithosphere rheology 90 interpretation of lower crustal resistivities 42-6 controlled by lithosphere temperature major crustal lineaments of anomalous structure and crustal thickness 90-2 resistivity 41-2 flexural rigidity parameter 90 normal resistivity in inactive regions 35-41 flexure by sediment loading during basin formation 91 element mobility, Am~tsoq gneisses 253,257 flow laws element transfer, solubility controlled 155 wet and dry quartz and olivine 82 enriched mantle hypothesis, ULG-MG-diorite 246 wet olivine 139-40 enrichment processes 359 fluid composition, lower crust 165 enrichment, superimposed 261 fluid inclusion data, interpretation of 162 entrainment 360, 363 fluid inclusion trails 310 Subject Index 381 fluid inclusions 168-9, 293 primary 336 aqueous 165 primary fluid inclusions 167 carbonic 161 prograde growth zonation 198, 202 constant density (isochoric) systems 162 secondary 336, 337 major types 164-5 garnet coronas and recrystallization 243 mono-phase gaseous 165 garnet granulite source 187 and rocks from the lower continental crust 161-71 garnet granulites 320, 365, 369 secondary 98 crustal 368 techniques for study 161-2 mafic 183 fluid mineral content, precipitation of 44 garnet peridotites 203 fluid pressure 95-6, I00 garnet pyroxenites 368 fluids garnet websterites 203 and acoustic impedance 17 garnet zoning 204 CO2-rich 227 garnet zoning profiles, retrograde 199, 202 compatible with peak metamorphic conditions 165, garnet-amphibole thermometer 343 166 garnet-biotite thermometer, temperature estimates 343 continuous recharge 46 garnet-clinopyroxene assemblages 284-6, 287 convective flow of 44 GDS (Geomagnetic Deep Sounding) studies 41 fluids in the earth's crust 95-103 geobarometers 167, 293 diagenetic to low-grade metamorphic rocks 96 mineralogical 299 high grade metamorphic rocks 99-101 geochronology, Caledonian-Hercynian orogenic events medium-grade metamorphic rocks 96, 98-9 201 fluids, source of (hydration of xenoliths) 346 geological age, ULG-MG-diorite body 242-3 folding 286 geophysical observations, rheological implications of, isoclinal 27, 32, 233 central Australian basins 143 large-scale 99 geosynclinal sediments, source of deep pressurized folds pore-water 114 injective 101 geosynclines 283 internal 98, 99 geotherm models 64 recumbent 29, 301 constraints 65 foliation 100, 222, 226, 228, 233,291,319, 355 geothermal anomalies 2 regional 265 'Urach body' 129 sub-horizontal 226 geothermal fields 41 foliation patch 18 geothermal gradients 72, 79, 82-3, 90, 103, 354 fore-arc, Andean-type belt 224 effect of on lithosphere strength 84-8 fore-arc basin, telescoped 226 geothermobarometry 169, 365, 371 fore-arc deposits, modern, andesitic geothermometers, Engeln granulites 316 volcaniclastics 174 geothermometry 291 fractional crystallization 258, 275 geotherms fractional crystallization and assimilation combined Cenozoic 363 246 central Australia 136 fractionation Clark and Ringwood 63 biotite 246 continental and oceanic I09 clinopyroxene 243 high heat flow 68 gabbro 359 high temperature truncation of 66-7 low-pressure 243 model 90-1 lower layered group 239 perturbed 346 fractionation processes, chemical 327 and significant strain rates 80 free water 9, 35, 44, 46 steady state, static (family) 66-7 sources of 44 transient 63 French Massif Central, granulitic xenoliths from 319- gneiss domes 101 28 gneisses 23, 32, 33, 199,203,215,225,226, 231,291,298, Furua Granulite Complex 165-7 299, 300, 305, 331,356 Fyfe Hills, Enderby Land, Antarctica, granulite-facies acid intermediate 197 gneisses 216 Am~tsoq 251,252, 253 amphibolite-biotite 303 gabbro fractionation 359 amphibolite-facies, Uivak gneisses 270 gabbros 222, 224, 232, 233,235,242, 331 Archaean 180 layered 239 Uivak I 261-72 cumulates 240 biotite-sillimanite 340, 343 galena 264 early Archaean 262 garnet 102, 170, 177, 183, 187, 188, 197, 199, 240, 265, layered 264 287, 288, 292, 309 leptinic 102 partial melting of a mafic source 183 migmatitic 265, 304 382 Subject Index gneisses (cont.) depletion phenomenon 212 nepheline 223-4, 226 felsic 102, 103 Nfik 251,252, 253 fluids in 163 recrystallized and migmatized 264 formation of 100 tonalite-trondhjemite 180 garnet 320, 365, 368,369 upper amphibolite-facies 213-14 high-P 368 Uivak II 262 hydration reactions 336 gneissic basement 223 intermediate pressure 167 gneissic foliation 299, 302 isotopic evolution of 312 Gondwanaland 109 khondalito-kinzigitic 320 graben Lewisian, depletion of 357 Central 11 low concentrations of heat-producing minerals 154 Viking 11 mafic 102, 103,280, 360, 365 grain boundaries 100 Lesotho 358 grain boundary migration I00 and retrograde hydration 148 grain creep 59 meta-igneous 320, 327 granite plutons 298, 303 metasedimentary 298 65,222, 257, 299, 305, 331 metasomatic regression 216-17 British Caledonian, late 225 pyroxene 55, 66, 369 Ivis~rtoq intrusions 258 REE patterns and metasomatic alteration 313-14 Strona Ceneri zone 247 residual 223 water-fluxed 154 retrogressed 319 granitic intrusions 103, 258 thermal properties of 65 granitic melts 99, 151 unretrogressed 218 K-rich 177 as xenoliths 161 granitoids 152, 319 granulitic lenses 319 Andean-type 225 granuloblastic texture 319 late Archaean 262 graphite 293 granitoids and the restite model 151 graphitic biotite gneiss 302 granoblastic microstructures 365 gravitational stress 52 granoblastic texture 164, 309, 319 gravity anomalies 53, 138 65, 148, 222, 251,258, 262, 267 central Australia 135, 137-8 granodioritic melts 99 S. India 301 granulite boundary, and high density CO2 165 gravity lineament 55 granulite complex, Finnish Lapland Great Glen Fault 14, 51 evaluation of P-T-X conditions of high-grade meta- greenschist facies 72, 73, 75 morphism 288-93 greenschist-facies assemblages 199 geology 283-4 greenschist-facies overprint 199 granulite complex 286-7 greenschists 148, 224 granulites and anatexites 288 greenstone belts 228 lithology and metamorphic evolution 284-8 Archaean 108 metamorphic development 286-93 Precambrian terrains 276 pyroxene-plagioclase rocks 287 Grenville belt, Canada 225 SW marginal zone 284, 286 greywacke 226 granulite domain greywackes metamorphosed 286 CO2 dominant fluid 169 Griffith theory, cohesive materials 96 pressures 169 pure water absent 169 half-graben 13 granulite facies metamorphism 165 halogens 154 granulite facies rocks 100-1 harzburgite 235 granulite suites harzburgite layers 239 average composition 279, 280-1 heat flow 84 Engeln/Eifel, petrography 309-10 constraints from 175-6 meta-igneous, abundance of cumulates 320 continental 175 metasedimentary 320, 322 continental crust 279 granulite-facies assemblages 193, 203 high and low 86 granulite-facies, dehydration of 254 in the mantle 66, 67 granulite-gneiss belts 226 reduced 66, 67 granulite-greenstone belts 226 surface 63, 65, 67 granulites 24, 65,224, 226, 228, 231,269, 279, 291,331, heat flow band, critical 88 332, 336-7, 340, 345, 352, 356, 363 heat flow data and current tectonic status, representa- basic 148, 372 tive regions 87 bulk composition, mafic 310, 312, 332, 336-7 heat flow density, surface 6 depleted 359 heat flow models, Colorado Plateau 345 Subject Index 383 heat flow observations central Australia 135-6 Inari-Kola 283, 284, 292, 293 heat producing elements 179 inclusions depletion in 211 mafic and ultramafic 264 migration of 214 primary 167 radioactive preservation of 165 expulsion of 228 Indus Suture 223 loss of 227 Indus-Tsangpo suture zone 204 vertical distribution of, Archaean crust 227 infiltration 315 heat production mantle-derived fluids 313 Archaean and post-Archaean crust 175-6 inhomogeneities, Hohenzollern Graben region 121 lower crust 65-6 Insubric Line (Fault Zone) 199, 239 natural, declining 228 intercumulus mineralogy 239 within the crust 68 intergranular fluid phase, composition of, Finnish heat sources 152-3 Lapland granulite complex 293 heat transfer 294 intergranular melt 98 advective 68 International Lithosphere Program 119 conductive 64, 66 Interungnek gneiss 264 convective 64, 67 interval velocities 2 heatflow modelling 71 intra-arc extension 222 heating during compression 199 intra-arc pull-aparts 72, 73 Hebron fiord monolith 264, 268-9 intracrustal differentiation and assimilation 149 Hercynian orogeny 323 intracrustal melting 175, 177, 214 High Himalaya 223, 225 intracrustal melting and crystallization: H20 154, 169 vertical tectonics and chemical structure 151-4 H20 isochores 164 volatiles in the crust--horizontal tectonics 154-6 H20-rich solutions 299 intracrustal recycling 150, 151 Hohenzollern Graben: seismicity and stress concentra- intraplate seismicity 119 tion 119-30 intraplate seismicity of the Hohenzollern Graben 119- crustal structure 121,125 30 horizontal reflections from the lower crust, published crustal structure of the Hohenzollern Graben 120-5 explanations 18-19 geological setting 119-20 235, 241 intraplate seismicity and crustal heterogeneities 127- HREE 239 30 HREE depletion 174 seismicity of the Hohenzollern Graben 120-1 in tonalites 184 stress-field in the Hohenzollern Graben region 125-7 HREE enrichment 322 intrusions, granitic 103 hydrated minerals 55-6 intrusives 149 hydration 332 island arcs 173, 221,224, 225, 226 early 337 basaltic, W. Pacific 222 secondary coalescence of 305 of mantle assemblages 155 collage of 225 and micro-cracks 337, 340 Kohistan-Ladakh 224 under low grade greenschist conditions 343 modern 221-2 hydraulic fractures isochemical conversion 299 microscopic and macroscopic 114, 116 isoclines, refolded 226 shortened crust 115 lsostasy 198 stretched crust 115 lSostatic balance 5 hydraulic fracturing 99 isostatic compensation 53, 82, 86, 87, 301 hydrofracturing 125, 127 isostatic crust, gravity values 7 hydrosphere 275 isostatic rising 276 hydrostatic pressure 96 mostatic uplift 293, 294 hydrothermal ore deposits 316 asotopic aggregates of common minerals 55 hydrous minerals 98 characteristic physical properties of 56 hypocentres, Hohenzollern Graben region 121, 127-8, isotopic characteristics crustal and mantle 218 129 isotopic characteristics, lower crust, generated during spatial projection of 130 crustal accretion-differentiation (CADS) 212-15 isotopic chronometers, resetting of 218 I-type granitoid 151, 153 isotopic disequilibrium 316 Iapetus Ocean, closure of 198 isotopic equilibration 316 Iapetus suture 16, 46, 52 isotopic geochemistry, typical bulk crust and mantle igneous intrusions, non-reflective 31 reservoirs 213 illite 96 Ivisgtrtoq region, W. Greenland ilmenite 291 age and isotope data 251 impedance contrasts 19 data interpretation 251 384 Subject Index

Ivis~irtoq region, W. Greenland (cont.) Lewisian gneiss 13, 15 geology 251,252 lherzolites 264, 365 Ivrea Zone 18, 30, 199, 231,232, 322 LIL depletion 258, 299, 300, 305-6 sequence of events 247 LIL elements 173, 211,254, 267, 269, 301 Ivrea Zone crust 72 metasomatic enrichment in 211,212 significant movement of 254 jadeite 199, 343 LIL enrichment 243 Jequi6 granulites 212 Uivak gneisses 267-8 Jos Plateau, Nigeria 75 limestones 300 K 154, 155, 175, 211,227, 242, 254, 312, 359 Limpopo Belt 101 depletion 258, 351,357 linear heat flow-heat production relationship 63, 65 K-feldspar 322 linear shear belts post-Archaean 301 K-metasomatism 299 LISPB refraction profile 52, 53, 54 K-rich granites 177 lithosphere 109-10 K/Rb ratios 270 elastic thickness of 113 tonalites 181 flexural strength of 79, 90, 92 kaersutite 241 and thermal age 91 Kangimut Sangmissoq, W Greenland 218 temperature structure 86 Kapuskasing Structural Zone (KSZ), Ontario 179, 180, thermally old 91 181,279 thermally young 91 Karelia-South Lapland craton 283, 284, 292 lithosphere and crust, evolution of 108 craton 297, 298, 304, 305 Phanerozoic times 109 Karnataka gneiss-greenstone terrain 305 pre-Archaean and Archaean times 108 kelyphites 204 Proterozoic times 108-9 Khondalite belt 301,305 lithosphere and crust, nature and strength of 109 khondalites 298, 300 lithosphere deformation (intraplate), mathematical kimberlite volatiles 155 model of 82-3 kimberlites 71,179, 316, 326, 351,352, 355 lithosphere extension, heat flow required 87 kinzigites 199 lithosphere strength, effect of crustal thickness and Kiyuktok gneisses 265, 270, 271 lower crustal composition 89-90 K20 240, 241,267, 268 lithosphere stretching 113 Eifel lower crustal suite 311 lithosphere temperature structure 85-6 Kohistan 224 lithosphere thickening, continental and oceanic 109 KSZ trondhjemites, major and trace element chemistry lithospheric extension 73, 74, 75 180 lithospheric mantle, rheological properties of 102 kyanite 187, 197, 294, 322, 337 lithospheric shortening 74 stability of 167 lithostatic pressure 79, I00 low velocity body (LVB) 2 La 235, 322 Eifel 315 Ladakh 224 low-stress, low-strength regions 86-7 lamellae 28 and detachment horizons 86, 92 concept of 1 lower continental crust of mafic granulites 102 composition 279-81 reflecting 7 composition estimates 276, 280, 281 large ion lithophile elements see LIL elements diversity in 71-6 Laurasian craton 201 lower crust Laurentian Shield 109 Archaean 188 layer-parallel slip 98-9 mafic 179 layered rocks, deep continental crust, physical proper- basaltic 305 ties of 51-60 cataclastic deformation 113 layered sequences 28-9 classification of 30-3 layered zones, as reflectors 27 composition 147 layering 371 differing perspectives 357 deep crustal ductile 227 alternative explanations 60 in eastern Australia 363-72 rational explanation 59-60 nature of lower crustal xenoliths 365-8 lower crustal, possible causes 71 recognition of lithologies 363-5 Lebombo Monocline 223 xenolith geochemistry 368-70 Lesotho granulite xenoliths 357 exposed sections 148 leucogranites 223 fluid composition in 165 leucosomes I00, 246 fluid recharging 76 granulitic 237 garnet granulite facies rocks 109 leucratic layers 265 granulite-facies rocks 100 Lewisian complex 217 heat production 65-6 Subject Index 385

high electrical conductivity 55 Uivak gneisses 267-8 horizontal reflections from 18-19 LREE movement 271 importance of volatiles 154 lamellar nature of 2-3 macrofractures 98 layered 16, 53, 71,371 mafic intrusions low resistivity layer 41 contaminated 244-5 mafic 179, 305 layered 29 eastern Australia 372 mafic minerals 337 metasedimentary component 31 mafic reservoir 247 mineralogy of 148 mafic source material 183 N. America, physical model based on seismic reflec- 149 tion data 23-33 basaltic 369 orogenic belts, structural evolution of 221-8 basic, lower crust 177 Archaean deep crust 226-7 calc-alkaline 247 Phanerozoic collisional orogenic belts 222-5 contamination of 214, 360 Proterozoic lower crust 225-6 fluid-rich 272 plastic deformation 113 fractional crystallization and assimilation of country possible average composition 55 rock 245 pressure-temperature estimates, representative sam- granitic 258 ples 340 picritic 358 principal periods of structure formation 115-16 primary 346 Proterozoic 225-6 tonalitic 227 reflective 7, 53 magmatic differentiation 276 refractory, granulitic 71 magmatic intrusions 60, 151 rheology of 79 magmatic thickening 69 seismic and flexural behaviour 112-13 magmatic underplating 227, 228 seismic reflections from round Britain 11-19 magmatism 110 discussion: what are the reflectors 17-19 Karoo 352 typical record 11-17 subduction zone 227 stable cratonic areas 351 magmatites 103 structure and composition of 28-33 magnetite 235 modelling 28-30 magnetotelluric and geomagnetic variation studies, thickened granulitic, large-scale zonation 323 Scotland 39, 40, 41 weak quartz rheology 86 main gabbro-diorite body, Val Sesia and Val Mastal- lower crust and upper mantle, model for development lone 232, 239-47 (Colorado Plateau) 344 chemistry 240-2 lower crustal composition 226-7 isotopic composition 242-3 estimates 280 isotopic constraints 244-7 is there a consensus? 147-9 petrogenesis 243-4 and lithosphere rheology 90 REE chemistry 242 primary magmas, intracrustal processes and the Malene supracrustal rocks 251,252, 257, 258 andesite model 149-51 mantle lower crustal deformation, critical role in continental late Archaean 270 lithosphere strength 79-92 olivine rheology 86 lower crustal granulites, low U and Th content 154 silicates 275 lower crustal heating 74 upper, poorly reflective 7, 9 lower crustal igneous intrusions 148 mantle assemblages, secondary hydration 155 lower crustal reflections 33 mantle convection 108 lower crustal resistivities, interpretation of 426 changes 109 lower crustal resistivity mantle degassing 33 anomalously high 37 mantle domains (old, enriched) and contamination 246 anomalously low 37 mantle heat flow 66, 67 normal 35, 36, 37 mantle sources, depleted, Protdrozoic 327 lower crustal segments, examples 225-6 mantle-derived volatiles rare gas signature 155 lower crustal xenolith suites, chemistry of 310-12 marbles 165, 224, 226, 300 lower layered group (LLG), Val Sesia 232, 233-9, 247 Markt kimberlite pipe 352 chemistry 235 mass balance 149 composition of parental liquid 239 to calculate lower crustal composition 148 isotopic composition 237-9 mass deformation due to cataclastic flow 110 petrography and mineral chemistry 233-5 mass transfer mobile silicate melts 100 LREE 239, 359 Massif Central, France 66, 223 LREE depletion 237 massifs, Variscan fold belt 201 LREE enrichment 188, 243, 247, 321,322 Maxwell rheology 141 Archaean tonalites and trondhjemites 177 Maxwell visco-elastic material 82 386 Subject Index melange 224 metasomatic alteration 313 melasomes 100 metasomatic enrichment, later 216 melt-restite models 152 metasomatie fluids 255, 258 melting, shallow hydrous 227 metasomatic flushing 218 melts, granitic 151 metasomatic models 313-15 metabasic rocks 231 metasomatic overprint 316 metabasites 199, 291 metasomatic regression granulites 217 Fe-rich 287 metasomatism 253, 258, 271 metagabbros 231 and REE enrichment 314 metagreywackes 319, 320 metasomatism (recent), and recrystallization 315 metamorphic low vapour stage 299 metatexites 286 metamorphic processes, prograde 44 metatexitic texture 320 metamorphic re-equilibration 244 Mg 269 metamorphic repartitioning 313 Mg-Fe exchange thermometers 340 metamorphic rocks MgO 239, 241 high-grade 99-101 micaschists 199 Sm-Nd data 216-17 microbreccia, serpentinized, ultramafic 331 metamorphism 76, 223-4, 239, 261,263, 264 microcracks 332, 346 Archaean 262, 263 caused by thermal expansion 347 Amitsoq gneisses, amphibolite-facies 257 microcrystals, cryptocrystalline 170 and crustal rheology 95-104 microfractures 98 and crustal rheology, three-layer crustal model 101-3 microprobe analyses 180 depletion during 360 microstructures 372 due to crustal shortening 114 igneous 365 due to crustal stretching 114 microthermometry 161,167 due to lithosphere deformation 114 middle crust, impermeable 44 from igneous intrusion 112 middle layered group (MLG), Val Sesia 232 from lithosphere deformation 112 Midland Valley of Scotland 51 granulite 211 , 98, 99-100, 100, 101,170,299 granulite belt, Finnish Lapland 283-94 migmatitic fabrics 99 granulite-facies 165, 201,203, 213, 215, 227, 23 I, 243, migmatitic melts 99 254, 258, 286, 293, 309, 313,327, 359 migrnatization 261,264, 267, 299 Caledonian orogeny 315 early Arehaean 264 depletion 358 migration 3 high pressure 328 mineral analyses 339 granulite-grade I 11 mineral assemblages and microstructures, lower crustal high-grade 100, 21 I, 212, 218, 284, 320 xenoliths, eastern Australia 366-7 late Archaean 253 mineral assemblages, water defcient 161 mobility during 270 mineral barometers 197, 352 polyphase 290 mineral equilibration 352, 354, 356 high-P 197, 199 mineral equilibria 360 Sesia-Lanzo rocks 201 mineral inclusion suites 204 influencing crustal strength and deformation style mineral parageneses, P-T data from 162 110-111 mineral precipitation 114, 116 inverted 102 mineral reactions in xenoliths from the Colorado isochemical 302 Plateau 331-47 late Archaean, Ivis~rtoq area 254 petrography and mineral chemistry 332-40 Nfik gneisses, granulite-facies 257 . hermobarometry 34(L4 prograde 74, 96-104, 101, I07, 211 mineral thermometers 193, 197 burial 113 mineral zoning 365 and crustal thickening 113 mineralogical assemblages re-equilibrated 322 texture of rocks produced 112 mineralogical re-equilibration partial 368 regional 98 mineralogy lower crust rocks 148 retrograde 107, 113, 336 minerals retrogressive, re-equilibration of rocks 293 idiomorphic 170 metapelites 66, 165 precipitated by cooling magmas 151 metasedimentary rocks 245~i minette necks and dykes 331 chemistry of 301 minettes 345 metasediments 293 mini-plates 225 granulite-facies 232 modal melting 187 origins of 227 Moho 2, 5, 17, 18, 26, 143, 149, 195 as reflectors 9 defined 16-17 subducted 305 depth undulation, central Australian basins 133, 137- Upernavik 270 8 Subject Index 387

echo-time to 11, 13, 15 Northern Suture, Pakistan 224 participating in deformation 141 Norway, southern, juvenile (mantle derived) origin for reflection from 121,124 CO2 170 seismic definition 371 Nfik gneisses, W Greenland 214, 251,252 transitional 372 accretion of 257 undulation model 138, 139 age and isotope data, 253-5, 255, 257 Moho high 52-3 derivation of 257 Moho zone, underplated 26 Nutliak assemblage 262 Mohr-Coulomb failure criterion 96 Nulliak supracrustal units 265 Moine and Outer Isles Seismic Traverse see MOIST Moine 13 Moine thrust 12, 13 obduction 71,222 MOIST 13-14, 46, 51 wedge 51, 52 BIRPS profile 11, 12 oblique stacking 305 line drawings of reflection profiles 14 ocean crust subducted, shallow melting of 228 molar NaC1 56 ocean fracture zones crustal generation 72, 73 Moldanubian Zone (Bohemian Massif) 203, 322 ocean ridge push force 86, 87 molten earth hypothesis 275 oceanic crust 107, 109-10 monoclines, and occurrence of diatremes 345 subducted 170-1,227, 284, 332 montmorillonite 96 trapped 149-50, 151 Moses Rock diatreme 331 oceanic lithosphere, subduction of 204 Mozambique mobile belt 165 oceanic material, subduction of 346 multi-isotopic studies, information from 215 oceanic plateaux, crustal generation 72, 73 muscovites 343 oceanic slab, stabilization of 372 mylonite zones 27, 31 olivine 80, 102, 239 mylonites 13, 17 Dorn law creep 82 as reflectors 31-2 rheology of 88, 89, 143 olivine tholeiite primary arc lava 149 N2 164, 165, 167 primary magma 151 N2 inclusions, late 169 ophiolites 51, 71,195, 199, 222, 223-4, 224, 226 Na 269 dismembered 223 Na-rich felsic rocks granulite terrains 179 orogenic belts NaC1, in brines 165, 169 Cordilleran 225 Namaqua-Natal fold belt 351,352 Himalayan 221 Nanga Parbat Massif 225 Himalayan-type 226 nappe complexes 99, 103 marginal continental shelves of 223 granulite facies 101 modern 221 supracrustal 103 Phanerozoic, collisional 222-5 nappe formation Archaean gneiss terrains 108 orogenic deformation 1 I0 nappe stack 32 compressive 1 I0 nappe translation 195 orogenic process 110 nappes 27 orogenies, Australian 133, 134 granulite facies 102 orogens and delamination 74 gravitational 103 orthogneisses 212 intracrustal 103 orthopyroxene 264, 265, 287, 292 Naver Slide 13 Ottawa collisional orogeny 225 Nb 242, 244 Outer Hebrides Fault (zone) 15 Nd 235, 272, 322, 359 overthrusting 45, 153, 227, 301 isotopic evolution of 214 at a continental collision zone 148 Nd isotopes 237 evolution diagram 237, 242, 245 P-wave velocity 53, 55 Nd-Sm data 269, 270 packing density 100 negative reflection polarity, Aachen-Nohes Venn thrust palaeocontinental rise 223 fault 2 palaeopressures 305 neosomes 265 distribution of 302-3 nepheline gneisses 223-4, 226 linked to lithology and degree of depletion 303 Ngalia Basin, central Australia sediment accumulation palaeosomes 100, 265, 270 134 palaeotemperature, mineralogical 299 Ni 174, 175, 235, 239, 241,244 palaeotemperatures 'hot spot' distribution 302 Nilgiri Hills 300 Palisades sill 31 North Slopes area, uplift 305 Palni Hills 300 southern flank, supracrustal sequences 305 Pan-African belts 225 norites 224 Pan-African tectonic event 165 388 Subject Index

Pannonian Basin 75 Piedmont Terrain, Appalachians 223 parageneses Piemonte Zone 199 H20 deficient 161 Pilbara Supergroup 174 relict 322 plagioclase 80, 188, 235, 239, 265 paragneisses 223, 224 main fractionating phase 242 paragonite 199, 336-7 primary fluid inclusions 167 parameter sensitivity, geotherm calculations 67-9 plagioclase fractionation 241 parental liquid, ULG-MG-diorite body 244 plagioclase rheology 89 partial leakage 167 plastic flow stress 110, 11 partial melt zones 71 plate boundary forces 82 partial melting 67, I I 1,151,217-18, 223,247, 257, 258, plate convergence 204 264, 315 plate tectonic processes 221 amphibolite 184 and evolution of the Finnish Lapland granulite belt basic rocks 251 293 garnet granulites 187 plate tectonics 109 granitic 254 plateau basalt provinces 75 mafic rocks 181,183 plates models 187 Asian 224 olivine tholeiite 203 Eurasian/Tibetan 223 partial pressure 167 Farollan 346 Pb 213,251,254, 269, 272 Indian 223 mobility of 253, 272 mini-plates 225 Pb isotopic ratios 253 platform sediments 109 Pb-isotopic evolution 212 plating 110 late Archaean rocks 216 pluton intrusion 76 retarded 216 plutonic activity 173 in Amitsoq gneisses 214 P205 241 Pb-Pb data Uivak gneisses 268, 269 Poisson's equation 64 Pb/Pb isotope data, Amitsoq and Nfik gneisses 254, 255 Poisson's ratio 55-6, 82, 90, 139 265 polymetamorphic areas 262 pelites 226 polymetamorphism 165 Peninsular Gneiss 297, 298 polyphase deformation 165 Penninic continental plate 199 Ponmudi charnockites 302 peridotite 74, 102, 197, 199, 224, 232, 235, 239, 316 pore fluids 108 peridotite massifs 102 mechanisms of movement 112 permeability 56-7 saline 154 anisotropic 44 pore pressures 56, 57, 59, 100 crystalline rocks 96 high 96, 110, 112 increased by metamorphism 112 pore water, pressurized zones of 113, 115 permeability coefficient and sedimentation rate 96, 97 pore-fluid pressure high, zones 112 perturbation, granulite data 167, 168 pore-water, hot migration of 114 petrogenesis 215 porosity and resistivity 44 of felsic gneisses 181,183 porosity and seismic velocity 19 petrogenesis of layered gabbros and ultramafic rocks, Precambrian shield, Canadian, composition of 275-82 Val Sesia and Ivrea Zone 231--48 early crustal evolution 275-8 geological setting 232-3 lower continental crust composition 279-81 lower layered group (LLG) 233-9 surface composition of the Precambrian shields 278- chemistry 235 9 composition of parental liquid 239 Precambrian shields isotopic composition 237-9 composition estimates 276, 278 petrography and mineral chemistry 233-5 surface composition of 278-9 main gabbro diorite body 239-47 pressure data, Finnish Lapland granulite complex 29 I- chemistry 240-2 3 isotopic constraints 244-7 pressure and temperature estimates petrogenesis 243-4 Furua Granulite Complex 165-7 REE chemistry 242-3 Southern Karnataka, India 166, 168-9 petrological data, central European Variscides 103 West Uusimaa Complex, Finland ?66, 168-9 petrology and geochemistry of the lower crust 147-56 primary magma 149, 151 lower crustal composition: is there a consensus? 147- pseudomorphs 336, 337 51 pull-up effects 52 phase stability studies 188 pyrometamorphism 319 phengites 199 pyrope 183 phenocrysts 152 pyroxene 102, 170 phyllite 224 pyroxene granulites 66, 269 Subject Index 389

pyroxenites 232, 233, 235, 239, 372 Uivak grey gneisses 267 nickeliferous 232 REE patterns of melts 185 reflecting horizons 9 Qianxi Group (China), granulite gneisses 215 reflecting layers, thickness of 18 Q6rqut granite complex 251,252, 255, 258 reflection density, normalized, histograms 6 quartz 72, 80, 102, 164, 265, 288, 337 reflection events 17 primary fluid inclusions 167 reflection profiles, simplified line drawings 16 rheology of 143 reflection seismology, USA, results from 23-33 quartz diorite 148, 149 deep crustal reflectors 27 quartz eclogites 170, 171 structure and composition of the lower crust 28-33 partial melting 187 reflection-rich offshore data 25 quartz monzonites 262 reflections quartz rheology 88, 89 from lower crust 15-I 7 quartzites 226, 300 multicyclic 28, 31 primary 12 radioactivity reflectivity 59-60 crustal 66, 67 and latest tectonic event 5 lower crust 68 reflectors surface 65 dipping 12, 17-18 upper crust 68 and fault zones 13 upper mantle 68 near vertical, reality of 1 radiogenic heating 153 steeply dipping, Saar-Nahe trough 1 radiogenic isotope evolution 211 upper mantle 14 radiogenic isotopes 64 relaxation time 141 radiogenic-isotope memory, erasure of 218 remobilization 222 radiometric dating, eclogites, blueschists 201 resistive zones, anomalously low 35 Raman microprobes 167 resistivity 35 Ramberg's equation 101 anomalous, major crustal lineaments of 41-2 ramps 15 low, hypotheses 45 rare earth analyses, Val Sesia complex 238 resistivity anomalies, elongated 41, 42, 43, 46 rare gas diffusion in minerals 316 restite entrained 152 Rb 154, 155, 181,211,213,227, 240, 254, 267, 268,269, restite melting 152 299, 312, 359 restites 76, 148, 152, 214 depletion 270, 300, 357, 358, 359 evidence for 150 enhancement 246 retrogression 59, 211,262, 305 enrichment 243 deformation induced 203 fractionation of 326 reworking 217-18 mobility 272 Rhenish Massif 309 Rb-Sr data, Uivak gneisses 268, 269, 270 crustal reflection line 1 Rb/Sr fractionation of 253 electrical resistivity structures 38 Rb/Sr ratios 21 I, 213,237, 242, 246, 251,314, 355, 356, magnetotelluric study 41 357, 358 xenolith studies 44-5 Rb-Sr systems 213, 237 rheological change 71 Uivak gneisses 270 rheological lithosphere model, central Australian rebound, regional, lack of in central Australian basins basins, coupled layers 140--1 139 rheology recrystallization 98, 112, 199, 239¢ 264, 299, 301 of the crust 19 concurrent 197 depth dependent 141 plutonic rocks 224 weak quartz replaced by stronger plagioclase 90 secondary 100 Rhine Graben static 203 en echelon structure 119 recycling, subduction related 151 taphrogenesis 119 REE and Ba concentrations, Archaean tonalite-trondh- Rhine Graben fault, reflectivity along short profile 1-2 jemite rocks 182 Rhine-Ruhr rift system 87 REE contents, equilibrium melts 187 ridge/trench interaction 72, 73 REE data Val Sesia complex 235 rifting, continental, and heat transfer 68 REE enrichment 311 rifts and metasomatism 314 active 87 REE partition coefficients 183, 184 intra-continental 223 REE partitioning behaviour 183 rock strength increased with pressure 110 REE patterns rocks, ductility of 19 Archaean and post-Archaean 173-4 root zones 151,319 Archaean tonalites and trondhjemites 177 Ryggedalsvatn, N. Norway 216 390 Subject Index

S-type granitoids 151,153 Sesia-Lanzo zone, Western Alps 199, 201 S-type leucogranite 153 Shansi graben sytem (China) 87 Saglek-Hebron fiord area shear belts, 109 Proterozoic effects 263 ductile 225, 226 structural pattern and metamorphic facies distribu- shear linear lineaments 119 tion 263 shear zones 60 Saglek-Hebron, N. Labrador, late Archaean high- Palaeozoic 17 grade metamorphism and granite injection 261- shearing 262, 286 72 Shevaroy Hills 300 saline fluid inclusions and electrical conductivity 59 shortened crust 113-14 saline fluids, low resistivity 46 hydraulic fractures 115 saline pore fluids 154 shortening 76 saline water, retained in anatectic rocks 60 Si 267, 269 Satyamangalam Supergroup 300 silicic melt 150 Saxony granulite mountains 101 sill complexes 72, 73 schistes lustr6s 199 sillimanite 288, 331,337 schists 331 sills 18, 19 Scottish Highlands 53, 59 gabbroic, intruded 3 I Scourian gneisses 213 SiO2 240 thermal model for 214 slide zones 19 Scourian granulites 216, 217 Sm 235 Pb isotopic composition 212 Sm/Nd fractionation 214 Scotland 181 Sm-Nd isotope system 313 Sr isotope data 213 Sm-Nd isotopic rejuvenation 313 sea floor spreading 63, 107, 109, 110 Sm/Nd ratios 237, 315, 355, 357 seal zone 76 Sm-Nd studies, timing and evolution of continental seamounts 72, 73 crust 214 Seconda Zona Dioritico-Kinzigitica (II DK), Sesia- Sm-Nd systems 237, 242, 271 Lanzo zone 199 source regions sedimentary accumulation Archaean tonalite-trondhjemite rocks 188 central Australian basins 133-4 Archaean upper mantle 212 crustal generation 72, 73 source rocks and heat sources 153 sedimentary prism 74 shield, major features 304, 305 seismic anisotropy 27 South India-Sri Lanka high-grade terrain 297-306 seismic conductivity 115 granulite-facies transition zone 298-300 seismic faulting 116 high grade massif 300-3 seismic reflection studies Peninsular gneiss-Vijayan complex 303-4 Germany 1 South Irish Sea lineament 13, 15 location 2 Southern Karnataka, India 167-8 seismic reflection surveys, central Australia 135 Southern Uplands 52 seismic reflections, lower crust round Britain 11-19 low resistivity lower crust 46 seismic reflectivity, high 107 spinel lherzolites 331 seismic reflector horizons 305 spinel periodotites 311,312, 315, 365, 371 seismic refraction data spreading ridge 74 and depth to Moho 370 Sr 187, 211,213, 235, 240, 251,254, 270, 312, 359 sub-horizontal reflectors 370 fractionation of 326 seismic refraction lines across BIRPS lines 11 Sr and Nd isotope analyses, French granulitic xenoliths seismic travel time anomalies, central Australia 135 324, 325-7 seismic velocities 19, 155, 332 Sr-isotopic evolution, late Archaean rocks 216 central Australian basin, variations in 137 Sr/Nd rdtios 245-7, 314, 359 as indicators of crustal maturation processes 5-9 stability fields 345 about the nature of crustal reflectors 7, 9 hydrated assemblages 340, 341,343 relationships between crustal viscosities and seismi- stacking velocities 2 city 6-7 static reaction textures 323 low 107 steady state creep silicate rocks 113 in xenoliths 345 stoping mechanism 151 seismicity 108, 113 strain analysis differential 56 and crustal viscosities 6-7 strain rates 95 upper and lower crust 95 competency contrasts 98 seismicity cut-off I 13 significant tectonic deformation 80 seismogram, synthetic 18 and temperature, 80, 81 sequential foreland propagation 204 strain-hardening 110, 116 serpentinite 224, 226, 331 due to dilatancy 112, 113 serpentinized ultramafic microbreccia (SUM) 331 strain-softening I10, 111, 112, 113, 116 Subject Index 391

strain, longitudinal-tangential 102, 103 SWAT lines dipping reflections 14-15 strength SWAT profiles 16 variation of with depth, and resulting stress distribu- Swaziland Supergroup 174 tion 83-4 symplectites 204, 336, 337, 368 vertical distribution of 79 fingerprint 337 stress synforms 251 creep release of 119 deviatoric 99, 100, 112-13 Tana belt 284, 293-4 effective 56 Tasman fold Belt, Palaeozoic 363 effective normal tectonic accretion 372 concept of 95-6 tectonic deformation 84, 88 negative 96 of lithosphere 79 horizontal 89 tectonic denudation 27 lateral applied 82 tectonic emplacement, mafic granulites and eclogites strain-rate dependent 95 102 vertical distribution of 79 tectonic evolution stress amplification 83 central Australian basins 140-3 stress corrosion 98 within an intracratonic environment 143 stress determination in situ, door stopper method 125-6 tectonic forces 86, 87, 276 stress field, central European rotation of 119 tectonic imbrication 199 stress relaxation 99 tectonic overprinting, retrograde-metamorphic 103 stress release by ductile deformation 86 tectonic pathways 74, 75 stress state, central Australian basins 138 tectonic regimes, horizontal 258 stress tensor, determination of, Hohenzollern Graben tectonic regions, active, and resistivity anomalies 41 region 126-7 tectonic slice, Austro-Alpine plate 199 stress-depth discontinuities 83 tectonic stress, and compaction disequilibria 96, 97 stresses tectonic stripping 198 effective 110 tectonic thickening of the upper plate 204 high 111 tectonic uplift 188 low 99, 113 tectonic windows 199 negative 99 tectonic zonality, lacking in the Archaean 221 zero 100 tectonics STRESSMAX (theoretical curves of maximum compressional 4 stresses) 6, 8 extensional 5 stretched crust 113 tectonites 96 hydraulic fractures 114, 115 gneissic 226 stretching 76 tectonometamorphic evolution, interpretation of 201 strike-slip movement 51 tectonometamorphic phase, Hercynian orogeny 201 structures and textures due to 'hot working' 114 tectonothermal events 215 sub-horizontal layering 12 tectonothermal model for eclogite formation in conti- subduction 76, 108, 109, 149, 188, 225 nental crust 196 A-type 195, 196, 205 temperature data, Finnish Lapland granulite complex Baltic plate 198 290-1 shallow, hydrated ocean rocks 155 temperature estimates, uncertain with depth 63 transient 204 temperatures subduction processes 69 anomalous high 315 subduction zone magmatism 227 and strain rates 80, 81 subduction-accretion prisms, crustal generation 72, 73 tensile forces 84, 87 sulphide mineralization 264 terminal collision processes 226 Suomussalmi gneisses 215 terrains, 69 supracrustal areas, S. India and Sri Lanka 300-3 accretion 75 supracrustal rocks 31, 32, 305 arc 51 Proterozoic 283 Archaean 251 suture zones 109, 195, 223-4, 226 gneiss-granulite 226 Indus-Tsangpo 204 heat flow 173 sutures 52 high grade 312 American/European continents 51 crystalline 32 collisional 224 deep crustal, Archaean, deformation 227 Iapetus 16, 46, 52 exotic, accreted 222 Indus 223 gneiss 226 Northern, Pakistan 224 polymetamorphic 272 Yarlung-Zangbo 224 gneiss-greenstone 297, 305 suturing 110 gneiss, Archaean 108 SWAT (Birps profile) 11, 12 Gondwana-derived 201 392 Subject Index terrains (cont.) thrust stack, Himalayan type 225 granite-greenstone 258 thrust stacking 74, 76 granulite 24, 167, 188, 351 thrust-nappe stack 204, 205, 223, 226 as deep crustal models 297 imbricated 195 multi-isotopic studies 215 thrusting 33, 223, 233, 294 Sri Lankan, layered rock 301 Archaean gneiss terrains 108 granulite-facies thrusts, reactivated 18 Archaean 211 Th/U ratios, tonalites 181 metamorphic 179 Ti 235,239, 312, 359 high grade, pre-Cambrian, crystalline 23 Tibetan Plateau 225 isotopic characteristics of 215-17 Tibetan-Himalayan belt 225 lower crustal 148 time sections, unmigrated 12, 13 28-9 TiOe 291 Pan African, N. Namibia 351 tonalites 174, 177, 222, 226, 227, 251,262, 267 South India-Sri Lanka 297-306 Archaean 184, 187 thermal models for 214 HREE depletion 184 transfer and assembly 75 mafic source 188 Tesseyre-Tornquist line I 1 tonalitic gneiss I80 Th 154, 155, 175, 176, 181,211,227, 312, 359 tonalitic-trondhjemitic rocks, geochemistry of 180-9 depletion 213, 351,357 Torridonian sandstone 13 thermal adjustment 291 trace element characteristics thermal conditions for some dynamic crustal processes Archaean and post-Archaean sediments 174 68, 69 Archaean tonalite-trondhjemite rocks 179-89 thermal conductivity 64, 66, 195 trace element enrichment 359-60 controls 64-6 trace element and isotope data, metaigneous rocks, Val profiles 65 Sesia and Val Mastellone 236 temperature dependence at depth 68 trace element ratios 239 thermal equilibrium 343 trace element studies and source mineralogy 152 thermal flux, enhanced 193 trace elements, rims, hydrated xenoliths 340 thermal gradients 198, 212, 351 transformation, deformation induced 203 lateral 258 transient creep 113 thermal gradients in the continental crust 63-9 translational movements, horizontal 227 family of steady state, static geotherms 66-7 troctolites 23 geotherm models 64 trondhjemites 171, 177, 184, 226, 227, 251, 258, 262, parameter sensitivity 67-9 267 thermophysical parameters 64-6 troughs, intra-cratonic 109 thermal heating 129 Tschermak's component 336 thermal history, rock suites 69 Tschermak's type substitute 343 thermal maturation 343 turbidite sequences thermal metamorphism 115 Archaean depositional sites 174 thermal perturbations 153, 198, 315 greenstone belts 174 and metamorphism 116 two-pyroxene thermometer 343,354 thermal properties, behaviour of with depth 63 two-stage model ULG-MG-diorite body 246-7 thermal re-equilibrium 59 thermal recovery (annealing) processes 113 U 154, 155, 175, 181,211,227, 269, 299, 312 thermal relaxation 195, 196, 204, 351 depletion 213, 351,358 retarded 204 mobility of 253, 272 thermal structure 204 Uivak 1 gneisses 261,262 thermal subsidence, central Australia 133-4 areas of contrasted late Archaean metamorphism thermal transition zone 291 and migmatization 264-5 thermally active regions 87 geochemistry and isotope chemistry 265-70 thermobarometry 203,204 Uivak I gneisses thermophysical parameters 64-6 amphibolite facies thickening 76 amphibolite/granulite facies transition 264 tholeiites 149 outer Saglek 264 continental 321 migmatized granulite-facies (Kiyuktok) 265 olivine 322 partially remobilized granulite facies 264-5 Th/Pb ratios 356, 358 Uivak II gneisses 262 thrust boundaries 75 U/Pb ratios 213, 356, 358 thrust faults, Palaeozoic 17 U-Pb systems 213 thrust restacking 71 ultrabasic layering 18 thrust sheets 226 underplating 31, 32, 68, 76, 258 allochthonous 223 basaltic 74, 75 thrust slices 319 magmatic 227, 228 Subject Index 393 underthrusting 195 volcano-plutonic zone 225 crustal wedges 204 Vredefort Dome, S Africa 71, 218 multiple 305 vulcanicity 88 Upernavik supracrustals 262 uplift 113, 223,328 Waldviertel (Lower Austria) 102 post-collisional 225 wall breakouts retarded 204 indicating orientation of crustal stress tensors 127 synorogenic 98 Urach well 125 uplift paths 169 water uplift trend, nearly isothermal 169 deep, preserved at high pressure 59 upper continental crust, composition of 281 importance of in the lower crust 154 upper crust low-pressure, survival of 59 metamorphic grade, French Central Massif 319 retention of in lower crust 59 silicic, radiogenic 71 water capture and retention 57-9 stretching of i 1 water fugacity 287, 288 upper layered group (ULG), Val Sesia 232 wave velocities, lower crust 279 upper mantle wavelength 98 eastern Australia 365 weathering 276, 327 metasomatism and hydration 346 wedging mechanism 52 pressure-temperature estimates, representative sam- welding 110 ples 340 Western Gneiss region, Norwegian Caledonides 197, upper mantle, newly formed 149 198 Urach 'body' 121 Western Isles and North Channel Traverse see WINCH structural details established 125 wet melting 66, 67 Urach geothermal anomaly 2, 129 Whole Lithosphere Failure (WLF) 84, 86, 87, 88 Urach geothermal research well (no. 3), refraction and critical force required 89, 90 reflection profiles 121-5 Wilson cycle 110, 223 Urach profiles, line drawings from 4 WINCH 14-15, 46, 51~50 Uusimaa Complex, Finland 168-9 interpretation 55-7 Moho high 52-3 V 235 physical properties of the lower crust below the Val Sesia, layered gabbro/ultramafic complex, Caledonides 53-5 sequences 232, 233 reflectivity 59~0 Val Strona, Italy 239 water capture and retention 57-9 Variscan collision zone 5 WINCH (BIRPS profile) 11, 12 Variscan crust, lower, deep seismic reflection Wind River Mountains 23-4, 72 profiling in Germany 1-9 Wind River Thrust 18 Aachen and Urach data 1978 2-3 windows, greenschist 226 early seismic data 1-2 Wollaston fold belt, Canada 226 histograms of reflections 3-5 seismic velocities as indicators of crustal maturation xenocrysts 343, 345 of processes 5-9 xenolithic fragments, study of 148 Variscan Front 13, 15, 16, 17 xenoliths 71,147, 188, 232 Variscan orogenic belt 319 aluminous garnet granulite 148 Variscan orogenic cycle 203 amphibolite-facies 356 Variscan orogeny 201,328 calc-alkaline 321 Variscides 2, 195, 204 crustal 332, 352 velocity gradient positive 103 southern Africa 360 velocity pull-down 17 whole rock analyses 337, 338 vent hydration 332, 343 in diatremes 155 vertical stretching 74 disaggregation of 346 Vijayan Complex, a remobilized terrain 304 eastern Australia 363, 364 Vijayan Gneiss Complex 298 eclogite 332, 334-5 Vikan granulites, N Norway, later depletion event 215 and microcracks 346 volatiles migration of 258 garnet websterite 363 volatiles in the crust--horizontal tectonics 154-6 garnet-granulite 352 volcanic arcs, 71, 72 N Lesotho 354 accreted 305 granulite 279, 354 volcanic sampling uncertainty 370 eastern Australia 368-70 volcanics 275 evolutionary trend 323 Tertiary, Canada 331 late stage deformation 337 volcanism 173, 258, 315 major and trace element concentrations 310 andesitic 174 normalized trace element abundances 311 basaltic 74 REE patterns, from Bournac 321 394 Subject Index xenoliths (cont.) mineral analyses, southern Africa 353 granulite-facies 310 modelled as cumulates 358 in alkali basalts 179 Moses Rock diatreme 345 Lesotho 356 position within the crust 324 granulitic, age of 327-8 sedimentary 239 granulitic, French Massif Central 319-28 Southern Africa 351-60 chemical affinities of 320 pressure-temperature estimates from crustal xeno- comparison with other granulite samples 322-7 liths 352-4 petrology of 319-20 regional geology 351-2 hydrated 337, 338, 340 Sr-, Nd- and Pb isotope results 354-7 late hydration 346 spinel-lherzolite 365 lherzolite 365 sub-continental mantle 359 limestone 343 ultramafic 331,332, 344 lower crustal 66, 175, 187, 21 I, 333 upper mantle 343 dominantly mafic 179 in volcanic lavas 161 granulite 309 Xigaze Group, Tibet 224 nature of 365, 368 stable tectonic regions 316 Y 235, 239, 241 mafic, Lesotho and Namaqualand 355 Yarlung-Zangbo suture 224 mantle 315, 332, 344, 352 Yb 242, 312 Westeifel 315 Young's modulus 82, 90 mantle-derived, isotope composition 213 meta-igneous 321 170, 242, 299 isotopic and trace element data 326 recrystallized 263 model ages 327-8 zoned 264, 265 metasedimentary 245, 320, 323,327 zoisite 199, 336, 337 micro-cracks 332 Zr 235, 239, 241