The silicate mantle and its dynamics have controlled the Earth's internal cooling for over four billion years. Today, these dynamics are rather slow, but this was not always the case: shortly after the core/mantle separation, this reservoir was significantly melted, with dynamics like those of a magma ocean. Despite advances in analytical and numerical tools and a better understanding of the Earth’s internal structure, the Earth's mantle currently remains a mystery. Structure and Dynamics of the Earth's Interior 1 presents the evolution of mantle dynamics throughout Earth’s history, from its formation to the present day. It examines the contributions of numerical modeling, as well as the seismological, petrological and geochemical data used to constrain dynamic models. Finally, the book analyzes the manifestations of mantle dynamics in terms of surface cooling, volcanism and coupling with the atmosphere.

Table of Contents:
Foreword xi Yanick RICARD Chapter 1 Models of Mantle Dynamics 1 Gaël CHOBLET 1.1 Toward the first models of the Earth’s mantle 1 1.1.1 Prior to the models 1 1.1.2 Continental drift, thermal convection and plate tectonics 3 1.2 The physical model: thermal convection 5 1.2.1 Conservation laws: mass, momentum, energy 6 1.2.2 Constitutive relationships: Fourier, rheology and equation of state 8 1.2.3 Boundary and initial conditions 9 1.2.4 Dimensioning, dimensional analysis and dimensionless numbers 10 1.2.5. From linear stability analysis to turbulent convection 12 1.3 “Solving” partial differential equations 16 1.3.1 Spectral methods 17 1.3.2 Finite-difference or finite-volume methods 18 1.3.3 Finite element methods 20 1.3.4 Various aspects of contemporary methods 21 1.4 From a reductionist to a holistic approach 24 1.4.1 Mixed heating 24 1.4.2 Sphericity 25 1.4.3 Rheology 26 1.4.4 Composition 31 1.4.5 Several phases 32 1.5 Conclusion 34 1.6 References 37 Chapter 2 How the Earth’s Core and Mantle are Separated: Geochemical and Dynamic Constraints 41 Julien MONTEUX and Maud BOYET 2.1 Introduction 41 2.2 How the Earth’s core and mantle are separated: geochemical clues 44 2.2.1 Internal composition model of the Earth and telluric planets 45 2.2.2 Chemical elements and their properties 46 2.2.3 Meteorites: Building blocks of the Earth 48 2.2.4 Constraints using moderately siderophile elements 52 2.2.5 Excessive concentration of HSE 53 2.3 Iron/silicate separation in a magma ocean 54 2.3.1 Fragmentation on impact 55 2.3.2 Fragmentation in the magma ocean 56 2.3.3 Thermochemical evolution of iron droplets 58 2.4 Iron/silicate separation by giant diapirism 61 2.5 Giant impact core assemblies 64 2.6 Conclusion and outlook for magnetic fields 66 2.7 References 68 Chapter 3 Dynamics and Thermal Evolution of the Earth’s Early Mantle 75 Julien MONTEUX and Denis ANDRAULT 3.1 Introduction 75 3.2 Primitive energy sources 76 3.2.1 Short-lived radioactive elements 77 3.2.2 Impact heating 79 3.2.3 Viscous dissipation related to core formation 81 3.2.4 Giant impacts and the Moon’s formation 82 3.3 Melting curves in the deep mantle 84 3.3.1 Mantle solidus profile: the temperature at which the first magmas formed 85 3.3.2. Melting curves for other silicates in the Earth’s mantle 87 3.3.3 Eutectic mantle melting diagram: example of the core/mantle boundary 88 3.3.4 Temperature constraints at the core/mantle boundary 91 3.4 The mantle during the magma ocean stage 91 3.4.1 A vigorous convection system 92 3.4.2 Magma ocean modeling 93 3.4.3 Adiabatic profiles 94 3.4.4 Cooling dynamics 95 3.5 From magma oceans to present-day mantle dynamics 97 3.5.1 Melt fraction rates and viscosity models 98 3.5.2 Cooling dynamics 101 3.5.3 Magma ocean-solid mantle coupling 102 3.5.4 Geochemical consequences 104 3.6 External influences 105 3.6.1 Relationship between the primitive mantle and the core 105 3.6.2 Influence of the primitive atmosphere 106 3.6.3 The Moon’s influence 106 3.7 Conclusion 107 3.8 References 108 Chapter 4 Hotspots, Large Igneous Provinces and Global Mantle Dynamics 115 Cinzia G. FARNETANI 4.1 Introduction 115 4.2 Active hotspots today 117 4.3 Geochemistry of hotspot lavas: long-lived and short-lived isotope systems, what do they tell us? 120 4.4 Seismic imaging below hotspots: To which extent do LLSVPs and ULVZs “feed” mantle plumes? 125 4.5 Plumes in the convecting mantle 127 4.6 Large igneous provinces 130 4.6.1 Phanerozoic continental flood basalts 130 4.6.2 Phanerozoic oceanic plateaus 134 4.6.3 Older LIPs and radiating dyke swarms 136 4.7 Environmental effects of Phanerozoic large igneous provinces 138 4.7.1. Factors triggering global warming and global cooling 140 4.7.2 Oceanic anoxia events: ocean acidification 141 4.7.3 Ozone depletion from halogen emissions: release of toxic metals 142 4.8 Concluding remarks 143 4.9 References 144 Chapter 5 Heat Flow and Secular Cooling of the Mantle 155 Stéphane LABROSSE 5.1 Introduction 155 5.2 Geophysics of the seafloor and the oceanic heat flow 156 5.2.1 Infinite half-space model 157 5.2.2 Observations: seafloor age and heat flow 158 5.2.3 Seafloor depth 162 5.2.4 Total oceanic heat loss 164 5.2.5 Link to mantle dynamics 168 5.3 Continental heat flow 172 5.4 Heat sources and secular evolution 175 5.5 Conclusion 180 5.6 References 181 Chapter 6 Noble Gases: Geochemical Tracers of Mantle Dynamics 187 Manuel Alexis MOREIRA 6.1 Introduction 187 6.2 Noble gases in the mantle 188 6.2.1 General information on noble gases 188 6.2.2 Noble gas analysis 194 6.3 The evolution of the mantle–atmosphere system 209 6.3.1 Outflows: mantle degassing 209 6.4 Past and present dynamics of the Earth’s mantle 215 6.4.1 A homogeneous asthenosphere through convection and/or efficient melting? 215 6.4.2 Noble gas constraints on magma ocean dynamics 218 6.5 Open questions on the origin and evolution of terrestrial noble gases 220 6.5.1 Helium concentration in island basalts 221 6.5.2 The origin of terrestrial neon (and of helium and hydrogen) 222 6.5.3 Missing xenon 223 6.6 References 224 List of Authors 239 Index 241