The course provides knowledge, competences and skills about the use of geophysical methods, with special focus on seismic reflection technique, in hydrocarbon exploration. The course is devoted to students with different backgrounds and it is aimed at supplying fundamental knowledge about seismic method principles and technologies, data processing and interpretation in the context of reservoir discovery, characterization and exploitation. The subject is inherently linked to reservoir modelling, drilling, petroleum geology end geomechanics.

The fundamental knowledge provided by the course during classroom lectures concerns signal processing methods used for geophysical data processing, petrophysical properties of rocks, and the physical phenomena which are used in seismic exploration (seismic wave propagation in natural heterogeneous materials). The course will deepen the geophysical exploration techniques focusing on seismic reflection method (with regards to technical and technological aspects of land and marine data acquisition, seismic signal processing methods and seismic data interpretation). The course aims at reaching competence in simplified seismic data modelling, processing and interpretation through individual computer lab work, during which, the students will apply the fundamental knowledge concepts provided during classroom lectures and implement simple modelling and processing tools that will enable them to consolidate their basic knowledge and improve their practical skills. Seismic data interpretation skill will be developed and trained during team work using industry data.

Fundamental knowledge of math, physics and geology are required.

Introduction: basic concepts of geophysical methods and applications (0.5 credits); Signal processing: analog-digital signal; frequency, amplitude, phase; Fourier analysis and synthesis; main features of amplitude and phase spectr; sampling and data loggers; impulse response and convolution integral; digital filters (1 credits) Seismic waves in layered media: seismic wave equations in homogeneous, isotropic, elastic media; seismic wave propagation in homogeneous, isotropic, elastic half-space: body and surface waves; wave fronts and Huygens principle; seismic wave propagation in layered media: seismic ray, Fermat principle and Snell law. Direct, reflected and refracted waves in layered media; the seismogram; seismic wave propagation in real media: attenuation. (1.3 credits). Seismic exploration: seismic acquisition technologies: sources, sensors, cables, data-loggers for land and marine surveys; seismic reflection: acquisition, logistic, multifold data and coverage, 2D and 3D; seismic reflection data processing: editing, filtering, static corrections, CMP sorting, deconvolution, velocity analysis, NMO correction, stacking, migration. (1.3 credits) Seismic interpretation: geological and structural interpretation, convolutional model and seismic resolution; amplitude interpretation: AVO and AVA basic principles, cross-plots and applications; seismic attributes: evolution, classification and applications; 4D seismic and reservoir monitoring. (2.5 credit) Petrophysics: physical properties of rocks: porosity, density, elastic moduli, permeability, effects of temperature and pressure gradients, effects of fluids; analytical and empirical relationships between physical properties and measured geophysical parameters. (1 credit) Inversion: forward and inverse problems in geophysics; linear inverse problems, weakly non-linear problems and strongly non-linear problems; information content of data; deterministic solution techniques: least squares, damping and regularization, data and model resolution matrices; stochastic solution techniques: Monte Carlo method, simulated annealing, neural networks and genetic algorithms; application to seismic tomography and acoustic impedance estimate. (0.4 credits)

The course is 80 hours long and it is organised as follows: about 46 hours are dedicated to lectures about fundamental and technical knowledge. During lectures students are often involved with questions and exercises carried out individually but discussed with the whole group of students to assess the comprehension of principles and theory. 18 hours are dedicated to computer lab individual assignments which are carried out by the students with the supervision of the professor and/or an expert assistant. This activity has the task of developing competence and deepening the understanding of fundamental principles and methods. about 16 hours are dedicated to seminars and practical lab with the additional presence of expert instructors from industry. The practical labs are carried out in teams using real industry data and are aimed at developping ability and interpretation skills.

Books of reference (available at Department library): W.M. Telford, L.P. Geldart e R.E.Sheriff: Applied Geophysics, Cambridge University Press M.B. Dobrin, C.H. Savit: Geophysical Prospecting, McGraw-Hill O. Ylmaz: Seismic data processing, SEG. M. Bacon, R. Simm, and T. Redshaw: 3D seismic interpretation. Cambridge University Press. Material available on the web (portale della didattica): lecture slides, limited portions of reference books; scientific papers (tutorial and basic papers) as further readings, collection of exercises; homework assignments.

Modalità di esame: Prova scritta (in aula); Prova orale obbligatoria;

Exam: Written test; Compulsory oral exam;

... The exam is aimed at evaluating knowledge, competences and skills acquired during the course. It consists on the evaluation of the computer lab assignments carried on during the course, a 2-hour written exam, and a mandatory oral exam. 1) The assignments 1, 2, and 3, if correctly made and delivered before deadline, will provide 1, 1.5, and 1.5 point respectively (maximum total points for the assignment 4). Assignments are not mandatory but, to be considered, at least one out of two lab class should be attended. (till 2016/17 only 2 assignment were carried out with max total point equal to 3).The points attributed to the individual assignments are added to the written exam mark. The points of the assignments cannot be used to reach the mark of 18/30. 2) The 2-hour written exam consists on opens questions about theoretical and technological topics (14 points) and a comprehensive exercise that, starting from a simplified geological model of a trap and on assumptions made by the students, is aimed at evaluating the comprehension of petrophysics and seismic data modelling (11 points). The maximum mark of the written exam is 25/30 (26/30 till 2016/2017). The exam is closed book but an equation sheet is provided. The minimum mark required to attend oral exam is 14/30. Minimum points to be obtained in the question part is 7. 3) The oral exam is mandatory and depends on the mark obtained on the written exam. If the mark on the written exam is higher or equal to 18/30, the oral exam will only concern the discussion of a journal paper chosen by the students in a list of paper provided on the course page. If the written exam mark is from 14/30 to 18/30 the oral exam will be based on a first part of questions and exercises and, if passed, on the discussion of a paper. The paper discussion mark goes from -2 to +4. Oral exam points are added to the written exam. No mobile phone or pad are allowed during the exam. Pocket calculator is required.

Gli studenti e le studentesse con disabilità o con Disturbi Specifici di Apprendimento (DSA), oltre alla segnalazione tramite procedura informatizzata, sono invitati a comunicare anche direttamente al/la docente titolare dell'insegnamento, con un preavviso non inferiore ad una settimana dall'avvio della sessione d'esame, gli strumenti compensativi concordati con l'Unità Special Needs, al fine di permettere al/la docente la declinazione più idonea in riferimento alla specifica tipologia di esame.