Learning objectives
At the end of the course, the students will be able to apply their knowledge and skills to understanding so as to:
identify, by examination of hand samples and thin sections, the three principal groups of rocks (igneous, metamorphic, sedimentary) outcropping on the Earth’s surface;
explain why a variety of igneous and metamorphic rocks built the Earth’s crust and upper mantle and how these rocks form.
In addition, the students will demonstrate their communication and learning skills critically explaining the geologic history of igneous and metamorphic rocks and their origin within the different Earth’s plate tectonic settings.
Prerequisites
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Course unit content
Frontal lessons.
The activity will be held in the class by the course leader. If there is a restriction due to the Covid-19, the possibility of following lessons through electronic means of communication (synchronously, via Teams; remotely, on Elly) will be given.
The course provides the fundamental concepts concerning how igneous, metamorphic and sedimentary rocks form and address processes that govern the rocks formation within the context of plate tectonics. Sequence of the course topics:
The Earth: formation; internal structure; cooling and “Plate Tectonics”; how the igneous, sedimentary, and metamorphic rocks form; the “Rock cycle”.
Igneous rocks: the causes of partial melting of the Earth’s mantle and crust; the “Phase Diagrams”; the physical properties of magma; processes associated with magma ascent and solidification in the Earth’s crust; mode of occurrence; classification; igneous rocks and their Plate Tectonic setting.
Sedimentary rocks (an introduction): how the different types of sediments form; classification; sedimentary rocks and their Plate Tectonic setting.
Metamorphic rocks: solid-state reactions; metamorphic reactions; textures; classification: metamorphic grade and Facies; the Barrow’s metamorphic Zones; graphical representation of metamorphic reactions; Plate Tectonic setting of the metamorphic Facies.
Full programme
The Earth: formation; internal structure; cooling and “Plate Tectonics”.
The tectonic settings into which the igneous, sedimentary, and metamorphic rocks form; the “Rock cycle”.
IGNEOUS ROCKS
How the igneous rocks form: the causes of partial melting of the Earth’s mantle and crust at the three main plate tectonic settings (intraplate; at divergent and at convergent plate boundaries); the physical properties of magma (density, viscosity, chemical diffusion); processes associated with the ascent and solidification of magma in the crust; processes associated to magmas erupting on the Earth’s surface; mode of occurrence of intrusive and extrusive igneous bodies; the melting and crystallization processes graphically explained in the “Phase Diagrams”)
SEDIMENTARY ROCKS (an introduction): how the different types of sediments form; classification; sedimentary rocks and their Plate Tectonic setting.
METAMORPHIC ROCKS
Changes occurring in a rock during metamorphism; textures of metamorphic rocks; the crystalloblastic series; minerals orientation; how rocks deform during metamorphism; migration of the chemical components during metamorphism; the difference between metamorphism and metasomatism.
Metamorphic grade and Facies: the study by Barrow (1893) and Eskola (1920); index minerals and isograd.
The metamorphic reactions: solid-solid; solid-fluid; oxidation-reduction.
Graphical representation of metamorphic reactions: the ACF, A’KF and AFM diagrams; the petrogenetic grids.
Plate tectonic significance of the metamorphic rocks.
Bibliography
Klein C., Philpotts A. (2017), EARTH MATERIALS: introduction to mineralogy and petrology, 2nd edition. Cambridge University Press
Klein C., Philpotts A. (2018), Mineralogia e petrografia (edizione italiana). Zanichelli
Teaching methods
The 12 credits of this course amount to a total of 124 hours, distributed as follows: 72 hours of laboratory-based exercises and 52 hours of lectures. In the hours of lectures, the teacher uses PowerPoint files that display the sequence of course topics. The files are available on Elly.
Formative evaluation will be done informally with discussions during each lesson, in order to check how much students have been understood.
Assessment methods and criteria
The exam is made of a written part and an oral part.
If there is a re-sit examination due to the Covid-19, the examination will be carried out remotely, via Teams.
The student is admitted to the oral after he has passed the written part.
The oral part of the exam is made of:
a review of the written part, in which the student is informed about the correction criteria and supply clarifications that may modify the judgment; then the student answers to review questions covering the course topics, in order to evaluate the level of the learning outcomes.
Other information
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