Tectonophysics

A.Y. 2019/2020
6
Max ECTS
42
Overall hours
SSD
FIS/06 GEO/10
Language
Italian
Learning objectives
The course is aimed at allowing the students to acquire the ability to understand and mathematically describe the main physical processes that occur within our planet, from the Earth's surface to the core-mantle boundary, with particular regard to phenomena that modify the Earth on time scales of 102 - 106 years. The mathematization of these processes is also relevant to reach the goal of making the changes that our planet undergoes understandable and collectively called global change.The student will be able to mathematically model the perturbations in the radial and tangential displacements and in the gravitational potential, now monitored by different geophysical and geodetic techniques, due to a wide range of Solid Earth phenomena, from the redistribution of masses on the Earth's surface (variations ofsea level, instability of mass in the glacial compartment of the planet, earthquakes) and within it (mantle convection), instability in the Earth's rotation.
Expected learning outcomes
At the end of the course the student will have acquired the following skills:
1) will know how to mathematize a realistic model of the Earth with spherical symmetry, self-gravitating and viscoelastic, in which the fundamental equations of conservation of momentum, of angular momentum and Poisson equation are developed in spherical harmonics;
2) will be able to derive in a completely analytical way the Green functions related to the perturbation of the gravitational potential and to the superficial deformations for surface and internal loads and dislocations for a spherical, self-gravitating and incompressible model, due to surface and internal mass redistributions and earthquakes;
3) will be able to use the results of the two previous points to mathematize the physics inherent to the global processes that the Earth undergoes, following the fusion taking place in the glacial compartment interacting with the solid part of the Earth, the variations of the average sea level and the earthquakes that occur both in the Pacific belt of fire and in Italy, for the purpose of a modern control of the territory in which we live;
4) will be able to model and interpret from the physical point of view the perturbations of the terrestrial rotation and of the gravitational potential, ascribable to the previous point 3), with connections to the current gravitational missions of ESA (European Space Agency) and NASA (National Aeronautics and Space Administration);
5) will know how to apply the acquired methodologies also to other planets and satellites of the Solar System, in particular to the Icy Moons, such as Europa, Ganymede and Callisto of Jupiter and Titan and Enceladus of Saturn;
6) will be able to autonomously manage the problems related to the previous points, thanks to the use of the textbook: Global Dynamics of the Earth - Applications of viscoelastic relaxation theory to Solid and Earth Planetary Geophysics, Roberto Sabadini, Bert Vermeersen and Gabriele Cambiotti ( Authors), Springer (Editor), second edition 2016.
Single course

This course cannot be attended as a single course. Please check our list of single courses to find the ones available for enrolment.

Course syllabus and organization

Single session

Lesson period
Second semester
Course syllabus
Brief introduction to the internal structure of the Earth. Differentiation in core, mantle and lithosphere and geophysical methodologies to determine their structure. Rheological properties of the Earth's mantle. Post-glacial rebound. Equations for the conservation of the momentum and Laplace equation for a spherical, self-gravitating, stratified and viscoelatic Earth model. Spherical harmonics development of the momentum and Laplace conservation equations. Determination of displacements, stress and gravitational potential (Green functions) induced by surface loads, internal mass anomalies and dislocations (seismic source) by the technique of normal modes and propagators. Analytical treatment in the case of an incompressible medium. Characterization of the solution for displacement, stress and gravitational potential in the elastic limit and in the transient, according to the elastic and rheological parameters; analysis through normal modes of the deformation, following disturbance, of the interfaces between media with different physical properties. Applications of Earth models to geodynamics and seismology.
Temporal variations of the long wavelength gravity field and applications to the field of space geodesy: comparison with the data SLR (Satellite Laser Ranging), GRACE (Gravity Recovery and Climatological Experiment, NASA) and GOCE (Gravity and steady state Ocean Circulation Explorer, ESA). Average sea level variations (secular component) induced by instability in the cryosphere and plate tectonics. Static crustal deformations induced by earthquakes and GPS (Global Positioning System) and SAR (Synthetic Aperture Radar) data interpretation.
Prerequisites for admission
Excellent preparation of basic Physics and Mathematics, in particular in the Mathematical Methods of Physics
Teaching methods
Traditional lessons on the blackboard, with complete derivation of the equations that translate the Physics of the Solid Earth processes into mathematics
Teaching Resources
Sabadini R., B. Vermerseen and G. Cambiotti (2016). Global Dynamics of the Earth: Applications of Viscoelastic Relaxation Theory to Solid-Earth and Planetary Geophysics. vol. 20, Springer, ISBN: 9789401775526, doi: 10.1007/978-94-017-7552-6
Assessment methods and Criteria
Oral examination
FIS/06 - PHYSICS OF THE EARTH AND OF THE CIRCUMTERRESTRIAL MEDIUM
GEO/10 - SOLID EARTH GEOPHYSICS
Lessons: 42 hours