The Solid Earth: An Introduction to Global Geophysics

726 Pages·2005·2.2 MB·English

The Solid Earth
FromthecitationforthePrestwichMedaloftheGeologicalSociety,1996
(awardedforthecontributionmadebyTheSolidEarthtogeophysicsteaching
andresearch)bythethenPresidentProfessorR.S.J.SparksF.R.S.
ThePrestwichMedalisgivenformajorcontributionstoearthscience,and
providesanopportunityfortheSocietytorecogniseachievementsinareasthat
canlieoutsidethetermsofreferenceofitsotherawards.Thisyear,the
PrestwichMedalhasbeengiventoMaryFowlerforthecontributionofher
book,TheSolidEarth,whichhashadanenormousimpact.Thebookhasbeen
acclaimedbytoday’sleadinggeophysicists.Thereisconsensusthat,although
therearemanybookscoveringvariousaspectsofgeophysics,thereareonlya
smallnumberthatcanbeseenaslandmarksinthesubject.Mary’sbookhas
beencomparedtoJeffreys’sTheEarthandHolmes’sPhysicalGeology.
TheSolidEarthisrecognisedbyherpeersasamonumentalcontribution.In
thisbookshedisplaysawideknowledgeofaverybroadrangeofgeological
andgeophysicaltopicsataveryhighlevel.Thebookprovidesabalancedand
thoroughlyresearchedaccountwhichisaccessibletoundergraduatesaswellas
toactiveresearchers.
Thebookhasbeendescribedasoneoftheoutstandingtextsinmodernearth
sciences.
(Geoscientist,GeologicalSociety,1996,Vol.6,No.5,p.24.)

The Solid Earth
An Introduction to Global Geophysics
SecondEdition
C. M. R. Fowler
Royal Holloway
University of London
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Fowler,C.M.R.
Thesolidearth:anintroductiontoglobalgeophysics/C.M.R.Fowler.–2nded.
p. cm.
Includesbibliographicalreferencesandindex.
ISBN0521584094(hardback)–ISBN0521893070(paperback)
1.Geophysics. 2.Earth. I.Title.
QC806.F625 2004
550–dc22 2003065424
ISBN0521584094hardback
ISBN0521893070paperback
TOMYFAMILY
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Contents
Prefacetothefirstedition page xi
Prefacetothesecondedition xv
Acknowledgementstothefirstedition xvi
Acknowledgementstothesecondedition xviii
1 Introduction 1
Referencesandbibliography 3
2 Tectonicsonasphere:thegeometryofplatetectonics 5
2.1 Platetectonics 5
2.2 AflatEarth 11
2.3 Rotationvectorsandrotationpoles 14
2.4 Present-dayplatemotions 15
2.5 Plateboundariescanchangewithtime 24
2.6 Triplejunctions 26
2.7 Absoluteplatemotions 32
Problems 37
Referencesandbibliography 40
3 Pastplatemotions 43
3.1 TheroleoftheEarth’smagneticfield 43
3.2 Datingtheoceanicplates 54
3.3 Reconstructionofpastplatemotions 67
Problems 93
Referencesandbibliography 94
4 SeismologyMeasuringtheinterior 100
4.1 WavesthroughtheEarth 100
4.2 Earthquakeseismology 111
4.3 Refractionseismology 140
4.4 Reflectionseismology 157
Problems 178
Referencesandbibliography 186
vii
viii Contents
5 Gravity 193
5.1 Introduction 193
5.2 Gravitationalpotentialandacceleration 193
5.3 GravityoftheEarth 196
5.4 TheshapeoftheEarth 198
5.5 Gravityanomalies 202
5.6 Observedgravityandgeoidanomalies 213
5.7 Flexureofthelithosphereandtheviscosityofthemantle 218
Problems 228
Referencesandbibliography 230
6 Geochronology 233
6.1 Introduction 233
6.2 Generaltheory 234
6.3 Rubidium–strontium 244
6.4 Uranium–lead 247
6.5 Thorium–lead 249
6.6 Potassium–argon 251
6.7 Argon–argon 252
6.8 Samarium–neodymium 254
6.9 Fission-trackdating 258
6.10 TheageoftheEarth 262
Problems 265
Referencesandbibliography 267
7 Heat 269
7.1 Introduction 269
7.2 Conductiveheatflow 270
7.3 Calculationofsimplegeotherms 275
7.4 Worldwideheatflow:totalheatlossfromtheEarth 285
7.5 Oceanicheatflow 288
7.6 Continentalheatflow 298
7.7 Theadiabatandmeltinginthemantle 303
7.8 Metamorphism:geothermsinthecontinentalcrust 308
Problems 321
Referencesandbibliography 323
8 ThedeepinterioroftheEarth 326
8.1 TheinternalstructureoftheEarth 326
8.2 Convectioninthemantle 353
8.3 Thecore 371
Referencesandbibliography 381
Contents ix
9 Theoceaniclithosphere:ridges,transforms,trenchesand
oceanicislands 391
9.1 Introduction 391
9.2 Theoceaniclithosphere 397
9.3 Thedeepstructureofmid-oceanridges 409
9.4 Theshallowstructureofmid-oceanridges 417
9.5 Transformfaults 440
9.6 Subductionzones 458
9.7 Oceanicislands 487
Problems 492
Referencesandbibliography 493
10 Thecontinentallithosphere 509
10.1 Introduction 509
10.2 Thegrowthofcontinents 517
10.3 Sedimentarybasinsandcontinentalmargins 557
10.4 Continentalriftzones 584
10.5 TheArchaean 595
Problems 601
Referencesandbibliography 602
Appendix1Scalars,vectorsanddifferentialoperators 615
Appendix2Theoryofelasticityandelasticwaves 620
Appendix3Geometryofraypathsandinversionofearthquake
body-wavetime–distancecurves 630
Appendix4Theleast-squaresmethod 636
Appendix5Theerrorfunction 638
Appendix6Unitsandsymbols 640
Appendix7Numericaldata 648
Appendix8TheIASP91Earthmodel 650
Appendix9ThePreliminaryReferenceEarthModel,isotropic
version–PREM 651
Appendix10TheModifiedMercalliIntensityScale(abridged
version) 654
Glossary 655
Index 666
Thecolourplatesaresituatedbetweenpages398and399.