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 - Types of well testing (DST, Production test, Limit test, Interference tests) > Clean-up > Data collection and QC - Gas and oil equations for a well located in a reservoir > Boundary effects > Closed reservoir (pseudo-steady state conditions) > Specialized plots for well-test interpretation - Introduction to pressure derivative analysis - Well tests interpretation with pressure derivatives: > Early time models > Middle time models > Late time models > Interference tests - Unconventional well testing (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 applying the methodologies presented and discussed during the lectures to case studies based on synthetic and real data, with increasing 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

Lecture slides; Exercises; Exercise with solutions ; Lab exercises;

Exam: Written test; Compulsory oral exam;

The exam is subdivided in two sections, one for Well Logging part and one for Well Testing part, both aimed at evaluating knowledge, competencies, and skills acquired during the course. 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. Well logging part The examination will be written and will consist of at least three questions concerning: • description of log tools technologies, physical principles of the measurements, derived parameters and interpretation, required corrections and uncertainties; • exercise on petrophysical parameters characterization; • quantitative interpretation of a set of well log measurements for a given formation interval. The exam is closed book and the equation sheet provided in the course material is allowed. The student will need a pocket calculator and a pen. Duration of the written test: 1.5 hours Well testing part The examination will consist of two parts. • A written test concerned with the theoretical parts, description of conventional and unconventional well test methodologies, interpretation models, well-test design and problem-solving. The test is closed-books. Duration of the written test: max 2 hours • An oral presentation (10 minutes) of a technical paper selected out of a list of papers on new and/or unconventional well tests provided by professors. A PowerPoint presentation is expected for the presentation; failure to submit the presentation within the assigned deadline implies the student will not be allowed to take the exam on the next exam date. The marks of the well-testing part will be calculated as follows: 10 points out of 30 based on the presentation & discussion of the paper; 20 points out of 30 based on the written test. The mark of Well Logging part ranges from 0/30 to 30/30 (positive from 18/30) The mark of Well Testing part ranges from 0/30 to 30/30 (positive from 18/30) The final mark is calculated as the average between Well Logging and Well Testing results. i.e.: Final Mark = round((WellLoggingMark + WellTestingMark)/2)

In addition to the message sent by the online system, students with disabilities or Specific Learning Disorders (SLD) are invited to directly inform the professor in charge of the course about the special arrangements for the exam that have been agreed with the Special Needs Unit. The professor has to be informed at least one week before the beginning of the examination session in order to provide students with the most suitable arrangements for each specific type of exam.