The course presents a remote sensing approach for the imaging of the subsurface and the identification of specific targets. Different physical approaches are studied from the basic principles up to the data collection and processing. The common framework is the generation and recording of a non destructive analysis signal (acoustic, elastic, electromagnetic) that propagates within the medium collecting information about its properties. Particular attention is posed on the identification of the observable parameters, on the resolution and reliability of the final image, on the potentiality of multi domain data integration.

The course shows also current case histories and applications (identification of contaminant plumes, pipeline integrity monitoring, exploration for fluids, rescue of survivors under ruins, automatic tracking of acoustic sources).

The students will be able to

D1. Knowledge and understanding.

• have an extended and multidisciplinary view on the remote sensing techniques and possibilities
• understand the physics behind each sounding method

D2. Applying knowledge and understanding.

• use specialized SW to simulate the "sounding" in a synthetic scenario (e.g. the elastic wave propagation in a layered medium) and to understand “experimentally” the theoretical principles
• participate and collaborate in geophysical field campaigns

D3. Making judgements. 

• for a given scenario, infer the sounding methods applicability
• for a given sounding method, define pros and limits.

D4. Communication.

• prepare and present a report of a geophysical imaging campaign, also with field campaigns and homeworks

D5. Lifelong learning skills

• describe and parameterize a problem
• design a solution flow chart

- Remote sensing framework

Source, receiver and analysis signal. Observability and resolution. 

Model space and data space: direct and inverse relations.

Inverse problem formalization. Reflectometry.

- Elastic and acoustic sensing

Elastic media: Hooke law, elastic wave equation, traveltime tomography.

Elastic prospection: refraction and reflection seismic.

Examples of application and analysis of case histories.

- Electrical and electromagnetic sensing

Electrical properties of the media. Resistivity.

Electrical prospection: data acquisition and inversion.

Electromagnetic wave propagation in low loss media. Conduction and displacement currents.

Electromagnetic prospection: ground conductivity meter, metal detector, Ground Penetrating Radar.

Examples of application and analysis of case histories.

- Multidomain data integration

Constitutive relations. Cross domain parameters and models.

Cooperative inversion, joint inversion.

Introductory courses in signal processing and mathematics.

During the course, the students are asked to use simulation SW of subsurface images construction, and to produce running examples. At the exam the students, individually, present and run the examples, collocating them in the general framework of the remote sensing techniques, and explaining the underlying physical principle.

The exam is oral and it is graded between 0 and 30 "cum laude".