B012725 - ENVIRONMENTAL GEOCHEMISTRY

Italian

Study of the geochemical processes underlying mechanisms of mobility concerning elements or chemical species with reference to the shallow environment. Acquisition of knowledge to manage geochemical data in a correct way, validate their correctness for an analytical point of view and to construct conceptual models able to describe the investigated phenomena in a critical way. Quantitative description of a geochemical system and evaluation of the effect of anthropical perturbations.

1) Principles of Environmental Geochemistry, G. Nelson Eby, Yhompson Brooks/Cole, ISBN 0-122-29061-5.

2) Geochemical and Biogeochemical reaction modelling, 2008, Craig B. Bethke, Cambridge University Press, ISBN 978-0-521-87554-7

3) Environmental applications of geochemical modeling, 2002, C. Zhu & G. Anderson, Cambridge University Press, isbn: 0-521-00577-9.

4) Metodi matematici e statistici per le scienze della Terra, 2006, Vol. III, Tecniche statistiche, A. Buccianti, F. Vlacci, F. Rosso, Liguori editore.

Aim of the course is the understanding of how geochemical systems work, with particular attention to the shallow environment, the mobility of elements and chemical species, the modality to quantify natural processes by using with criticism graphical and numerical methods

Knowledge acquired in the courses of Chemistry, Physics, Mathematics, Geochemistry, Mineralogy and Petrography

Contact class with use of blackboard, video-projector for computer, overhead projector; possibility of practical lessons for data analysis in computer room. Use of the Moodle platform for e-learning for exchange of materials with students. Seminars and lessons by expert researchers on specific items could be proposed.

6 CFU, frequency of lessons is highly recommended, but not mandatory;

Oral exam with discussion of a scientific article given by the teacher. Questions on the developed program of the course.

Nature of the data used in geochemistry. Graphical and numerical methods to analyse geochemical data. Experimental errors and method to manage its presence. Laws of error propagation. Analysis of geochemical data on a time-space point of view. Deterministic and statistic methods.
Evaluation of geochemical hazard, determination of background values, identification of anomalous geochemical values on a time-space point of view. The role of the thematic maps.
Thermodynamical description of the chemical equilibrium, influence of the reaction kinetics. Box models and geochemical cycles. Application examples.
Thermodynamical modelling of natural processes. Chemical reactions and Law of Mass Action. Gibbs energy. Enthalpy and entropy. Activity and fugacity. Calculus of the activity coefficients. Concept of chemical potential. Direct and indirect determination of the constant equilibrium values. Modelling of reactions to describe weathering, oxidation and reduction, sorption and ion exchange, surface complexation, speciation and solubility processes. Activity diagrams, Eh-pH diagrams: construction, analysis and interpretation.
Preparation and construction of a geochemical model. Equations to be used for a multi-components modelling. Accuracy and completeness of the model.
Pollution of water resources, evaluation of the problems on a different scale. Analysis of international reports, identification of the planetary thresholds, concept of ecological fingerprint.
Radioactive and stable isotopes to be used to follow the development of natural or anthropical perturbation phenomena in the shallow environment. Application examples.
Presentation and discussion of case studies.