G9811k Geochemistry of exogenous processes

Faculty of Science
Autumn 2020
Extent and Intensity
2/1/0. 5 credit(s). Type of Completion: zk (examination).
Teacher(s)
Mgr. Pavel Pracný, Ph.D. (lecturer)
Mgr. et Mgr. Veronika Synková (assistant)
Guaranteed by
Mgr. Pavel Pracný, Ph.D.
Department of Geological Sciences – Earth Sciences Section – Faculty of Science
Contact Person: doc. Mgr. Martin Ivanov, Dr.
Supplier department: Department of Geological Sciences – Earth Sciences Section – Faculty of Science
Timetable
Fri 16. 10. 12:00–14:00 G2,02003, Fri 29. 1. 10:00–16:00 G2,02003, Fri 5. 2. 9:00–10:00 G2,02003
Prerequisites (in Czech)
! G9810 Geochem. exogen. proc. && ( (!(PROGRAM(B-GE)||PROGRAM(N-GE)||PROGRAM(D-GE4)||PROGRAM(D-GE)||PROGRAM(C-CV))) || (NOW( G0101 Occupational healt and safety )&&NOW( C7777 Handling chemicals )))
Course Enrolment Limitations
The course is also offered to the students of the fields other than those the course is directly associated with.
The capacity limit for the course is 28 student(s).
Current registration and enrolment status: enrolled: 0/28, only registered: 0/28, only registered with preference (fields directly associated with the programme): 0/28
fields of study / plans the course is directly associated with
Course objectives
Main objectives can be summarized as advanced understanding of the geochemical processes proceeding under conditions of earth surface, especially:
- physical/chemical/thermodynamic/kinetic aspects of rock weathering
- diffuse model of rock-water interaction
- reaction model - the transition state theory
- nucleation and crystal growth
- geochemistry of clay minerals
- equilibrium models of Al-pH and Al-Si-pH systems
- diagrams of predominant stability in the systems of Na-Al-Si-H2O, K-Al-Si-H2O, and Ca-Al-Si-H2O
- dynamic model of weathering in open system under different climatic conditions
Learning outcomes
Student will be able to:
  • a) distinguish which weathering processes take place in individual environments.
    b) explain basic theories in the background of water-rock interactions (diffusion model, transition state theory, nucleation and crystal growth ...).
  • c) create the equilibrium model of Al-pH, Al-Si-pH.
  • d) compare the data in the stability charts.
  • e) make a dynamic model of weathering in an open system with the involving of climatic changes.
  • f) summarize geochemical processes acting on the selected site.
    • Syllabus
    • Rocks stability at surface conditions: Non-stability of igneous and metamorphic rocks. Rock system evolution. Entropy and Gibb's energy. Goldish's scheme.
    • Rock weathering: Physical and chemical weathering. Aluminosilicate weathering. Reversibility and irreversibility of processes. The model of diffusion through surface layer. The model of surface reaction. The role of atmosphere and waters. The buffering of waters by CO2. Biogeochemical processes.
    • The kinetics of rock-water interaction: Experiments. Box-models. Mass reservoirs, fluxes. Rate equations, rate constants. Steady state, equilibrium. Arhenius' equation. Pre-exponential factor. Activation energy.
    • Transition State Theory: Elementary processes. Theory of activated complex. Modeling, computation. Potential barrier. Thermodynamic approach. Rate of interaction. Chemical affinity.
    • Saturation state: Thermodynamics of dissolution. Saturation index. Supersaturation, equilibrium and under-saturation of solutions.
    • Nucleation theory: Thermodynamics of surfaces. Interfacial surface energy. Polymerization, condensation. Homogenous and heterogeneous nucleation. Clusters, nuclea, and critical nucleus. Potential barrier. Supersaturation influence.
    • Crystal growth: Growth mechanisms. Ostwald's step rule, re-crystallization. The formation of secondary mineral phases. Dioctaedral gibbsite layer. Trioctaedral brucite layer. Amorphous SiO2 gels, quartz stability.
    • Clay minerals: 1:1 layer minerals: kaolinite, halloysite. Stability and solubility. 2:1 layer minerals: smectite (pyrophyllite, montmorillonite, beidellite), vermiculite. 2:1:1 layer minerals: chlorites.
    • Models of secondary phase formation: Al-pH system, equilibrium boundary, solution and mineral stabilities. Al-Si-H2O system, kaolinite, gibbsite, and pyrophyllite stability.
    • Diagrams of predominant stability: Na-Al-Si-H2O, K-Al-Si-H2O, Ca-Al-Si-H2O systems. Construction. Stability fields. Equilibrium lines. Reaction path and system evolution.
    • Dynamic model of rock weathering: Influence of climatic condition. Annual precipitation. Drainage. Soil water composition and concentrations.
    Literature
      recommended literature
    • BAUER, Andreas and Bruce D. VELDE. Geochemistry at the earth's surface : movement of chemical elements. Berlin: Springer, 2014, 315 stran. ISBN 9783642313585. info
    • STUMM, Werner and James J. MORGAN. Aquatic chemistry : chemical equilibria and rates in natural waters. New York: John Wiley & Sons, 1995, xvi, 1022. ISBN 0-471-51184-6-. info
    • APPELO, C.A.J. and D. POSTMA. Geochemistry, Groundwater and Polution. 1st ed. Rotterdam/Brookfield: A.A.Balkema, 1994, 519 pp. ISBN 905410 106 7. info
    • DREVER, James I. The Geochemistry of Natural Waters. Prentice Hall, 1997, 450 pp. ISBN 0-13-272790-0. info
      not specified
    • RYAN, Peter Crowley. Environmental and low temperature geochemistry. First published. Chichester, West Sussex, UK: Wiley Blackwell, 2014, xi, 402. ISBN 9781405186124. info
    • Chemical weathering rates of silicate minerals. Edited by Art F. White - Susan Louise Brantley. Washington, D.C.: Mineralogical Society of America, 1995, xv, 583. ISBN 0939950383. info
    • PFEIFFER, Hubert, Thomas KLUPSCH and Werner HAUBENREISSER. Microscopic theory of crystal growth. Berlin: Akademie-Verlag, 1989, 400 s. ISBN 3055006844. info
    Teaching methods
    Lectures, reading, seminars
    Assessment methods
    2 written tests, final test. In the case of a crisis pandemic situation, the course will be completed in the autumn semester of 2020 by distance form.
    Language of instruction
    Czech
    Further comments (probably available only in Czech)
    Study Materials
    The course is taught once in two years.
    Information on the per-term frequency of the course: Bude otevřen v podzimním semestru 2018/2019.
    Listed among pre-requisites of other courses
    The course is also listed under the following terms Autumn 2022, Autumn 2024.
    • Enrolment Statistics (Autumn 2020, recent)
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