The course aims at providing the knowledge needed to investigate and characterize hydrocarbon reservoirs through well measurements. Specific goals of the course are to provide the ability to perform the analysis, quality check and interpretation of static measurements recorded via well logging for determining the hydrocarbon volume initially in place and of dynamic measurements recorded via well testing for assessing the production potential of the system. To this end the course will focus on the equipment available for data gathering, testing procedures, uncertainties associated to well measurements, interpretation models, pressure transient analysis and their applicability and/or limitations. The skills gained in the course will allow the students to acquire the competences needed to efficiently communicate with experts from other disciplines who can provide scientific and technical insights or design constraints for an effective reservoir characterization. Attitude to an accurate and meticulous approach to data analysis and management is an essential trait of this course.

Students will acquire: - Deep knowledge of the technologies and methodologies applied for the characterization of hydrocarbon-bearing formations through geophysical logs as well as through the analysis of pressure transients (well tests). - Ability to handle the methods and software adopted worldwide in the oil industry for static and dynamic reservoir characterization based on a good understanding the principles and assumptions they rely upon. - Ability to unlock the key technical information from data, graphs, and other convenient tools or representations. - Ability to capture the essential messages, the methodologies and their implications from technical papers and manuals.

Students should have a good knowledge of geophysics, geology, fluid mechanics and reservoir engineering to be able to truly understand well measurements, which are the basis for reservoir rock characterization and estimation of the hydrocarbon in place and for describing the reservoir dynamic behavior and production performance. It is essential that students master the concepts and the basics of rock and fluid properties and their mutual interactions, the flow equations, and the pressure analysis and interpretation techniques. Familiarity with the orders of magnitude of the most relevant quantities (fluid properties, petrophysical characteristics, fluid-rock interaction properties, recovery mechanisms) is required.

- Introduction to well logging - Geophysical log technologies: measurements, correlations and corrections: > Lithological logs – self potential and gamma ray > Resistivity logs > Radioactivity logs – neutron and density logs > Sonic logs > Other logs – image logs, NMR - Log interpretation – formation evaluation: > Zonation and lithology recognition (clay index) > Use of neutron – density crossplot > Porosity, net to gross and water saturation estimation > Log inversion - Introduction to well testing - Equipment, data collection, and QC - Types of well testing (DST, Production test, Limit test, Interference tests) - Gas and oil equations for well production from a closed reservoir - Build-up equation and Horner plot - Introduction to pressure derivatives - Well tests interpretation with pressure derivatives: > Early time models > Middle time models > Late time models > Interference tests - Unconventional well testing (mini-DST, injection testing, harmonic testing)

Some of the theoretical lessons will be held with the collaboration of highly qualified technical staff from oil and/or service companies, who will give lectures on applications to real cases.

Exercises will include application of the methodologies presented and discussed during lectures to case studies based on synthetic and real data, with increasing degree of complexity. The software commonly adopted in the oil industry for log analysis and well test analysis will be used. Under the guidance of the professor, students will be encouraged to work independently.

Bourdet D., 2002. Well test analysis: the use of advanced interpretation models. Elsevier. Horne R., 2001. Computed aided well test analysis, Stanford University, Petroway Inc. Technical Papers will be provided (unlimited free download from the SPE One-Petro library is also available) The slides presented during lectures will be periodically posted on the course website

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

Exam: Written test; Optional oral exam;

... The assessment of acquired knowledge and technical skills occurs through written exams on the theoretical parts and on applicative aspects. The capability to integrate knowledge gained in other courses and contexts, to critically examine a technical problem and to select models and methods to reach the solution is expected. The exam will comprise true/false options, multiple choice questions, open questions, and problem solving. The exam is closed books. Each answer will be assigned marks depending on the complexity of the question. Oral integration is up to the students, provided that the minimum marks for passing the exam (18/30) have been reached. The oral integration can modify the score of the written exam by plus or minus 2 point maximum.

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.