Earth Physics

Academic Year 2023/2024 - Teacher: ANDREA CANNATA

Expected Learning Outcomes

The main objective is to provide students with the basic notions of geophysics and the tools necessary to process and use geophysical data.

Knowledge and understanding:

- theoretical bases of subsoil investigation techniques, such as refraction seismic, reflection seismic, gravimetric and magnetic prospecting;

- theoretical bases concerning the Earth's gravitational and magnetic fields;

- theoretical bases on earthquakes and seismic sources.

Ability to apply knowledge:

- ability to apply the knowledge acquired for the interpretation of geophysical data in order to characterize the subsoil;

- ability to understand the physical properties of the Earth system;

- ability to understand seismic phenomena and their hazard.

Autonomy of judgment

- ability to argue personal interpretations regarding geophysical investigations and data.

Communication skills

- ability of expository synthesis and use of appropriate technical-scientific language.

Course Structure

Face to face.

Should teaching be carried out in mixed mode or remotely, it may be necessary to introduce changes with respect to previous statements, in line with the programme planned and outlined in the syllabus.

Required Prerequisites

To understand the topics covered in the teaching, the knowledge of basic notions of mathematics and physics is important.

Attendance of Lessons

Mandatory.

Detailed Course Content

Introduction: definition of geophysics, spectral analysis, convolution, cross-correlation, digital filtering.

Planet Earth: the discovery of the planets, Kepler's laws of planetary motion, orbital parameters, characteristics of the planets, Titius-Bode law, angular momentum, origin of the solar system.

Gravitational field and gravimetric methods: physical bases, variation of g with latitude, shape of the Earth, geoid, measuring instruments, gravity corrections, interpretations of gravity anomalies, applications.

Earth's magnetic field and magnetic methods: basic concepts, magnetic properties of materials, the earth's magnetic field, measuring instruments, surveys, magnetic anomalies, applications.

Applied seismology - basics: stress and strain, seismic waves, propagation, seismic sources, recording of seismic signals.

Seismic refraction: critical refraction and head waves, half-space, horizontal layer, two horizontal layers, horizontal multi-layers, inclined layer, survey, applications.

Reflection seismic: general considerations, equation of reflected waves, reflected waves and depth, reflected waves and velocity, method t2 - x2.

Earthquakes: elastic rebound, seismic cycle, fault geometry, focal mechanisms, locations, magnitude and intensity, seismograms, internal structure of the Earth.

 

Exercises on magnetic and gravimetric methods.

Exercises in applied seismology.

Exercises on reading earthquake seismograms, magnitudes and locations.

Textbook Information

1.      Kearey et al. (2002). An Introduction to Geophysical Exploration. Wiley-Blackwell.

2.      Lowrie (2007). Fundamentals of Geophysics, Second edition. Cambridge University Press.

3.      Reynolds (2011). An introduction to applied and environmental geophysics. John Wiley & Sons.

4.      New Manual of Seismological Observatory Practice (NMSOP-2). https://bib.telegrafenberg.de/publizieren/bibliotheksverlag/nmsop

5.      Stein, S., Wysession, M. (2003). An Introduction to Seismology, Earthquakes, and Earth Structure. Blackwell Publishing.

6.      Havskov, J., Ottemoller, L. (2010). Routine Data Processing in Earthquake Seismology. Springer.

7.      Lecture notes.

Course Planning

 SubjectsText References
1IntroductionAn Introduction to Geophysical Exploration. Cap. 2. Notes.
2Planet Earth Fundamentals of Geophysics. Cap. 1. Notes.
3Gravitational field and gravimetric methods.An introduction to applied and environmental geophysics. Cap. 2. Fundamentals of Geophysics. Cap. 2. Notes.
4Earth's magnetic field and magnetic methodsAn introduction to applied and environmental geophysics. Cap. 3. Notes.
5Applied seismology - basicsAn introduction to applied and environmental geophysics. Cap. 4. Notes.
6Seismic refractionAn introduction to applied and environmental geophysics. Cap. 5. An Introduction to Geophysical Exploration. Cap. 5. Notes.
7Reflection seismicAn Introduction to Geophysical Exploration. Cap. 4. Notes.
8EarthquakesAn Introduction to Seismology, Earthquakes, and Earth Structure. Cap. 4.1, 4.2. Routine Data Processing in Earthquake Seismology. Cap. 5.1, 5.2, 5.3, 5.5. New Manual of Seismological Observatory Practice. Cap. 3.2. Notes.

Learning Assessment

Learning Assessment Procedures

The exam consists of an oral test of about 30 minutes aimed at ascertaining the level of knowledge and understanding reached by the student on the theoretical and methodological contents indicated in the program. Students will be able to begin the exam with the presentation of a topic of their choice.

Verification of learning can also be carried out remotely, should the conditions require it.

Examples of frequently asked questions and / or exercises

Talk about gravity acceleration measurements.

Illustrate the different magnetic behaviors of materials.

Explain what is meant by regional and residual gravity anomaly, and how they can be separated.

Describe measuring instruments in geomagnetic methods.

Describe the seismic sources you know.

What is the Titius-Bode law?

Talk about Kepler's laws.

Travel time of direct, refracted and reflected waves.

Talk about focal mechanisms.

Describe the process of locating an earthquake.

Talk about the internal structure of the Earth.

VERSIONE IN ITALIANO