The course provides an introduction to the thermodynamic equilibria that govern rock-forming processes, along with the related graphical representation methods. It introduces the principles of rock classification and identification, and analyzes, from a chemical and physical perspective, the fundamental concepts underlying endogenous and exogenous processes that control the formation and transformation of rock materials at the lithospheric scale.
The course provides a description of the Earth's interior, offering knowledge on the petrogenesis of igneous, sedimentary, and metamorphic rocks. Once students have acquired the tools to apply genetic criteria in distinguishing the three main rock groups, the program introduces classification diagrams to assign the correct nomenclature to rocks.
Classroom exercises using rock collection samples are designed to demonstrate, clarify, and apply the analytical procedure for rock identification. The integration of these steps leads to the correct naming of rocks using scientifically validated classification diagrams.
A further specific learning objective within the field of natural sciences is to understand the driving forces behind lithospheric dynamics and the relationship between rock textures and their evolution within the endogenic and/or exogenic cycle. Students should be able to discuss the relevance of a rock to specific petrogenetic environments, based on its texture, mineralogical composition, and, where possible, chemical composition.
Finally, a key learning goal of the course is to equip students with the tools necessary to correctly recognize, interpret, and classify rocks—essential skills for successfully following third-year Earth Science courses, which are closely related and build upon this foundational knowledge.
Teaching Methods
Frontal Lectures Lectures are held in the classroom and delivered using PowerPoint presentations and the consultation of selected web resources.
Practical Exercises Practical sessions are based on demonstration analyses and one-to-one discussions of rock specimens from the DISTAV teaching collection. When needed, a 3D projector is used to support the analysis.
Indoor Laboratory Activities These sessions take place in classrooms equipped with microscopes and dedicated lighting. Students are required to bring a 10x hand lens and a steel point to perform the so-called scratch test (relative microhardness evaluation).
Field Excursions Field trips will be organized in geologically significant areas of Liguria (e.g., Apennine and Alpine ophiolites) to apply rock classification criteria covered in lectures and to learn how to record geolithological data on geological maps.
Accessibility Students with a valid certification of physical or learning disabilities filed with the University, who wish to discuss possible accommodations or other academic concerns, are encouraged to contact both the course instructor and Professor Sara Ferrando (sara.ferrando@unige.it), the Department’s disability advisor.
Course Outline
Introduction
Overview of Earth's composition and structure
Fundamentals of global tectonics
Endogenic and exogenic dynamics
Petrogenetic Processes a) Magmatic Processes: definition and properties of magma; melt generation; melt dynamics within the crust; solidification of melts; magmatic crystallization b) Sedimentary Processes: weathering, erosion, transport, precipitation, and diagenesis c) Metamorphic Processes: recrystallization; thermodynamic factors and limits of metamorphism
Igneous Rocks
Introduction to the petrology of magmatic processes: silicate melts and magma—chemical and physical properties
Melt genesis and solidification: crystallization of silicate melts
Binary phase diagrams and their application to natural systems
Magma evolution: fractional crystallization, differentiation trends, miscibility and immiscibility, assimilation
Solidification environments; nucleation and growth rates
Principles of igneous rock classification
Magmatic series and variation diagrams
Relationship between magmatic series and geodynamic settings
Sedimentary Rocks
Classification based on depositional processes and compositional features
Environmental significance and sedimentary sequences
Introduction to pedology
Metamorphic Rocks
Controlling factors of metamorphism: thermodynamic and kinetic controls, role of time
Types of metamorphism and their crustal settings
Metamorphic recrystallization and reaction kinetics
Reversibility and chemographic representation of reactions
Paragenetic assemblages and their stability fields
Recrystallization and deformation; textures of metamorphic rocks
Representation of metamorphic reactions in P–T diagrams
Metamorphic facies, geothermal gradients, and facies series
Metamorphism and geotectonic settings
Practical Sessions on Igneous Rocks
Rock identification methods: structure, mineralogical and chemical composition
Minerals in igneous rocks: structural and chemical properties; macroscopic and microscopic recognition; equilibrium relationships with melts
Intrusive, extrusive, and subvolcanic rocks: structures and textures
Classification of igneous rocks
Practical Sessions on Metamorphic Rocks
Minerals in metamorphic rocks: structural and chemical properties
Macroscopic and microscopic identification
Structures and textures of metamorphic rocks
Practical Sessions on Sedimentary Rocks
Macroscopic recognition of textural and mineralogical features
Classification methods
Klein & Philpots - Mineralogia e petrografia. Zanichelli Editore
Morbidelli L. – Le rocce e I loro costituenti. Bardi Editore
Winter J.D. - An introduction to igneous and metamorphic petrology - Prentice Hall
Available (by download from Aula WEB) the Power Point slides used during lessons.
Ricevimento: The meeting is to be arranged with the teacher via phone, email, or AulaWeb.
From March 1, 2021. Consult the site of the study course for updates.
PETROGRAPHY
The attending student may take the exam through three written tests and three rock identification assessments during the semester. At the end of the lectures, the final oral interview to assign the grade is based on a summary of any deficiencies found and possible further discussions. The final grade is based on the three written tests, but it is not necessarily their arithmetic average.
Alternatively, the student may register for the official exam sessions held throughout the year. The exam consists of: i) classification of a rock sample provided during the exam, ii) three questions on igneous, sedimentary, and metamorphic processes, and iii) one question related to fieldwork exercises.
The three written tests during the semester are evaluated based on logical consistency, appropriate use of technical-scientific language, and the ability to apply what has been learned in class.
The final oral interview at the end of the course aims to assess whether the student's preparation has become more solid compared to previous weeks, and whether the student has critically addressed and filled any knowledge gaps identified in the written tests.
The traditional exam session evaluates, through questions ranging from simple to complex, the depth and accuracy of the student's knowledge (factual content), the ability to organize this knowledge into a rational framework, the ability to draw on prerequisite knowledge from Inorganic Chemistry and Mineralogy, and the ability to interrelate connected topics.
A passing grade corresponds to the ability to classify a rock (igneous, sedimentary, or metamorphic) using proper nomenclature criteria, providing justification for their application.
Regular attendance is strongly recommended, especially for field exercises. Students are required to have appropriate clothing for excursions (hiking boots) and a hand lens.
Students who have valid certification of physical or learning disabilities on file with the University and who wish to discuss possible accommodations or other circumstances regarding lectures, coursework and exams, should speak both with the instructor and with Professor Sara Ferrando (sara.ferrando@unige.it), the Department’s disability liaison.
