GEOPHYSICAL METHODS OF EXPLORATION

The course provides adequate knowledge of the main investigation techniques in the field of applied geophysics to the infrastructure and environmental, in order to characterize physical and mechanical properties of soils.

1. Geophysical prospecting techniques: seismic Theory and exercises on the main seismic prospecting methods to determine the elastic properties of lithotypes. 1.1. Basic concepts of seismic refraction method. 1.2. Active and passive seismic tomography theory. 1.3. Surficial waves dispersion properties: MASW, REMI and 2D array. 1.4. Speedy method to define seismic site effects with VS,30. 1.5. Seismic field exercises and processing through open source code. 1.6. Basic concepts of seismic reflection and study cases examples. 2. Geophysical prospecting techniques: geoelectric Theory and exercises on the main geoelectric prospecting methods to determine the subsoil structure and computer exercises. 2.1. Electric properties of the soils: application, advantages and disadvantages of the methodologies. 2.2. Passive and active geoelectric surveys. 2.3. Electrode configurations (Wenner, Schlumberger, Dipolo-Dipolo). 2.4. Basic concepts of geoeletric tomography. 2.4. Study cases and computer exercises. 3. Seismic site response estimates through 1D modelling: 1D modelling theory to determine the main seismic site response parameters and computer exercises. 3.1. Basic concepts: seismic signal spectrum, topographic effects, basin effects and stratigraphic effects. 3.2. Terrain non-linearity and theoretical background of the 1D model for seismic site response. 3.3. Seismic record parameters: PGA, PGV, PGD, RMS acceleration, Arias and Housner intensity. 3.4. Elastic response spectrum in acceleration, displacement and velocity. 3.5. Characteristic earthquake: deterministic and probabilistic approaches. 3.6. DISS, DBMI and CPTI catalogs to characterize the territory seismicity and seismic waves attenuation laws. 3.7. National seismic hazard map and NTC08 response spectra to select accelerograms for 1D modelling. 3.8. Open source software Rexel to select accelerograms (exercises). 3.9. Open source software Deepsoil and Strata to compute 1D seismic site response (exercises) 4. Experimental methods to determine seismic site response: Seismic site response methodologies based on earthquake and ambient vibration records. 4.1. Signal to noise ratio and earthquake duration. 4.2. P and S waves picking. 4.3. Spectral ratio techniques for site response analysis. 4.4. Directional seismic site effects: basic concepts, polarization analysis theory, and rotate spectral ratio method. 4.5. Evaluation of building dynamic properties (fundamental period, torsional effects and damping). 4.6. Open source Geopsy to compute Fourier spectrum and spectral ratios (HVSR and SSR).

1. P. Kearey, M. Brooks, I. Hill - An Introduction to Geophysical Exploration , Blackwell science
2. G. Lombardo - Geofisica delle aree urbane, Aracne editrice
3. Alan E. Mussett, M. Aftab Khan - Esplorazione del sottosuolo. Una introduzione alla geofisica applicata, Zanichelli