|SCIENTIFIC DISCIPLINARY SECTOR||GEO/09|
Petrography is a discipline describing the Earth rocks: this theoric and practical class provides the elements of igneous, sedimentary and metamorphic petrogenesis, with particular concern to textures and microtextures as they control the performance and the weathering of stones. This class is particularly devoted to cultural heritage as for the analysis of materials relevant to the art history, and for investigation and prevention of stone weathering.
The course aims at providing the theoretical tools to identify and classify stone materials, and at correlating the petrographic analysis with the corresponding technical characteristics, in order to develop a forecasting potential on the durability of materials. Lab and field exercises are planned.
The teaching provides elements of igneous, sedimentary and metamorphic petrogenesis. Having acquired the tools to use the genetic criteria in distinguishing the three rock groups, the program aims at explaining and demonstrating the classification diagrams for the correct and sound nomenclature of rocks and stones. Besides, the commercil nomenclature is compared. The analyis and comprehension of the sedimentary process gives the opportunity of drawing the comparison between rocks exposed at the Earth surface and stone buildings, affected by the same agents.
The exercises on the collection of rocks aims at demonstrating, make understood and to apply the steps of a rock analysis. The integration of the different steps leads to a stone denomination based on robust scientifc diagrams.
A further learning outcome, specific for the cultural heritage is the comprehension of the significance of technical properties (mechanical, thermic) of stones. Hence, based on the capacity of identfying and evidencing the textural and microabric of rocks, the aims of this section of the class is to connect the petrographic analysis with the corresponding technical properties, in order to develop a previsional skill on the durability of stones. Exercises in the laboratory and in outdoor surveys are tools of the teaching.
In order to get the most out of this class, having attended to Mineralogy applied to Cultural Heritage is strongly suggested, in particular for the mineral systematics (theoric part) and mineral identification (Theory and exercises).
Front lessons in the classroom. Front lessons are supported by power point presentations and thematic websites.
Exercises. Practical exercises are based on demostrative rock analyses and discussion on the specimens of the didactic rock collection at Distav. Rock samples are discussed B2B and, if necessary, with the aid of a 3D projector. In the final part of the teaching a demostration at the Laboratory of Scanning Electron Microscopy and / or a technical survey on Genoa building, and / or a technical survey to the Staglieno Monumental Cemetery is included.
The indoor exercises are kept in a dedicated classroom, with microscopes and specific lightning. The pupils are asked to come with a 10x magnification lens and a steel blade to carry out the scratch test (relative microhardness).
Origin of igneous, sedimentary and metamorphic rocks. Principles of classification of igneous, sedimentary and metamorphic rocks.
Methods of macroscopic identifications; highlights on other methods. Technical properties of rocks: Physical pproperties (specific weight, volume weight, heap weight, real and apparent porosity, gelivity, imbibition coefficient, thermal conductivity, thermal dilatation, fire resistance). Mechanical properties (compressive strength, tensile strength, flexural strength, impact resistance, hardness, microhardness, workability).
Defects in ornamental stones: color, pigmentation and color stability. weathering and durability.
For each property the relationships with mineral composition and rock fabric will be describes, together with the product test of the reference normative, also with examples on commercial stones.
L. MORBIDELLI, Le rocce e i loro costituenti. Bardi Ed. 2014
E.M. WINKLER, Stone in architecture. Springler Verlag, Berlin, 1994
Normative CEN e UNI
Siegesmund S, Snethlage R. (eds) 2011. Stone in Architecture, Properties, Durability Fourth edition, Springer, DOI 10.1007/978-3-642-14475-2
The power point presentations of lessons are availbale on Aulaweb for download.
Office hours: The meeting is to be agreed with the teacher, via telephone, email, aulaweb.
LAURA GAGGERO (President)
ROBERTO CABELLA (President Substitute)
The lessons of the first semester will start from September 30th 2019 and will end by January 17th 2020, the lessons of the second semester will start from February 17th 2020 and will end by June 12th 2020. Consult detailed timetable at the following link: https://easyacademy.unige.it/portalestudenti/
The examination is an oral test. Questions on the teaching topics are the bulòk of the examination. Secondly, the comprehension of a thematic book chapter or scientific article assigned by the teacher will be verified by the compilation of a power point presentation that will be discussed.
The exam is oral and consists of a question on the classification criteria of the rocks. If the need to verify the ability to identify the elements of a rock emerges from the question, the student may be submitted a sample of stone material for discussion.
This is associated with the critical reading and return in the form of a power point presentation of a scientific article, generally in English, on an agreed topic. The oral exam is conducted by two tenured professors (or in limited cases by a tenured professor and a subject expert designated by the CCS) and lasts for about 30 minutes.
The exam assesses logic, the appropriate use of technical-scientific language, the ability to apply what has been learned in the classroom. The exam tends to verify, through questions from simple to complex, the depth and correctness of knowledge (notions), the ability to organize them in a rational scheme, the ability to draw on the preparatory knowledge of Inorganic Chemistry and Mineralogy, the ability to correlate related topics.
The sufficient mark corresponds to the ability to classify a rock (magmatic, sedimentary or metamorphic) with the nomenclatural criteria, motivating its application.
Regular frequency is strongly recommended. The course includes laboratory exercises and technical visits to selected destinations (monuments / laboratories / museums / quarries).