This volume opens up new perspectives on the physics of the Earth's interior for graduate students and researchers working in the fields of geophysics and geodesy. It looks at our planet in an integrated fashion, linking the physics of its interior to the geophysical and geodetic techniques that record, over a broad spectrum of spatial wavelengths, the ongoing modifications in the shape and gravity field of the planet. Basic issues related to the rheological properties of the Earth's mantle and to its slow deformation will be understood, in both mathematical and physical terms, within the framework of an analytical normal mode relaxation theory. Fundamentals of this theory are developed in the first, tutorial part. The second part deals with a wide range of applications, ranging from changes in the Earth's rotation to post-seismic deformation and sea-level variations induced by post-glacial rebound. In the study of the physics of the Earth's interior, the book bridges the gap between seismology and geodynamics.
Normal Mode Theory In Viscoelasticity. 1. Derivation of the equation of motion 2. Expansion in spherical harmonics: spheroidal and toroidal solutions 3. Fundamental, spheroidal matrix in the Laplace domain 3. Propagator matrix technique 5. Inverse relaxation times for simple, incompressible Earth models 6. Phase-change interface 7. Loading the Earth 8. Approximation method for high-degree harmonics. Multi-Layer Models. 1. Analytical development of stratified, viscoelastic Earth models 2. Shallow inversions in PREM density stratification 3. Volume- averaged vs. fixed-boundary contrast 4. Isolation functions. Rotational Dynamics Of Viscoelastic Planets. 1. Introduction to Earth rotation 2. Rotational changes for a rigid Earth 3. Developments of linearized rotation theories 4. Long-term behavior of the rotation equation. Polar Wander And J2 Induced By Ice-Sheet Loading. 1. The concept of True Polar Wander (TPW) 2. Loading 3. Mantle Viscosity 4. Inference of lithospheric thickness from TPW and length of day variations 5. Ice age cycles and polar wander path 6. The influence of phase-change versus chemical stratification of the mantle 7. The impact of mantle stratification on TPW during the ice ages. Detection Of The Time-Dependent Gravity Field And Global Change. 1. Changes in the long wavelength geoid components analyzed by Satellite Laser Ranging Techniques 2. Trade-off between lower mantle viscosity and present-day mass imbalance in Antarctica and Greenland. Sea-Level Changes. 1. Introduction 2. Sea-level changes, geoid and gravity anomalies due to Pleistocene deglaciation 3. Glacial Isustatic Adjustment (GIA) vs. tectonic processes: the example of the Mediterranean Sea 4. Sea-level fluctuations induced by polar wander 5. Sea-level changes induced by subduction. Tectonics And The Rotation Of The Earth And Terrestrial Planets. 1. Mountain building and Earth rotation 2. Subduction’s effects on TPW. Pots-Seismic Deformation. 1. Global post-seismic deformation 2. Post-seismic deformation for shallow earthquakes. Appendices