Geochemistry of sedimentary carbonates


Environmental and Regional Studies (3rd level)

Paleobiology and sedimentary geology (3rd Cycle)

Course code: DIP07
Year of study: without

Course principals:
Assist. Prof. Špela Goričan, Ph. D.
Assoc. Prof. Aleksander Horvat, Ph. D.


Workload: lectures 30 hours, seminar 10 hours, tutorial 20 hours, individual work 120 hours
Course type: modul elective
Languages: Slovene, English
Learning and teaching methods: lectures, e-learning, seminars, practical training


Course syllabus (download)


Inscription to the 1st academic year.


Content (Syllabus outline):

  • Long-term carbon cycle.
  • Mineralogy, chemistry and reaction kinetics of major carbonate phases (calcite, dolomite, aragonite).
  • The CO2-carbonic acid system and solution chemistry.
  • Interactions between carbonate minerals and solutions.
  • Coprecipitation reactions and solid solutions of carbonate minerals.
  • Biologically formed and biologically induced carbonate precipitation.
  • The oceanic carbonate system and preservation of deep-sea carbonates.
  • Composition and source of shallow-water carbonate sediments
  • Early diagenesis.
  • Burial and metamorphism.
  • δ13C, δ18O, 87Sr/86Sr, trace elements and REE incorporation: paleoenvironmental vs. diagenetic proxies.
  • Short-term carbon cycle and human impact.



Selected chapters and papers:

  • Morse JW, Mackenzie FT (1990) Geochemistry of sedimentary carbonates. Elsevier, Amsterdam.
  • Holland H, Turekian K, eds. (2014) Treatise on Geochemistry, izbrana poglavja iz 9: Sediments, Diagenesis and Sedimentary Rocks, in Vol. 7: Surface and Groundwater, Weathering and Soils.
  • Morse JW, Arvidson RS, Luttge A (2007) Calcium carbonate formation and dissolution. Chemical Reviews 107: 342-381.
  • Machel HG (2004) Concepts and models of dolomitization: a critical reappraisal. In: Braithwaite CJR, Rizzi G, Darke G (eds) The Geometry and Petrogenesis of Dolomite Hydrocarbon Reservoirs, Special Publication 235. Geological Society, London, 7-63.


Objectives and competences:

The purpose of the course is to deepen the knowledge on the occurrence of carbonate minerals and sediments in different environments. Students will learn and know how to use the basic physico-chemical limitations and conditions which affect formation of carbonate minerals and sediments. The students will gain an overview of geochemical proxy indicators currently in use for the reconstruction of past environmental and diagenetic conditions. This knowledge enables interpretation of paleoenvironment and diagenesis of recent and older carbonates and carbonate rocks.


Intended learning outcomes:

Knowledge and understanding:

The student knows the basic aspects of carbonate minerals, and their interaction with the aqueous solution. He/she differentiates between early carbonate precipitates in different surface environments from later diagenetic and metamorphic overprints. In order to interpret the paleoenvironment of carbonate rock formation and assess the diagenetic overprints, he/she is able to use a wide range of geochemical proxies. When interpreting the (paleo)environment and changes on the Earth’s surface he/she is able to define the role of the global carbon cycle.



Written or oral exam (60 %), presentation of a chosen topic (40 %).


Assoc. Prof. Aleksander Horvat, Ph. D.

Research Fellow at Ivan Rakovec Institute of Palaeontology, Research Centre of the Slovenian Academy of Sciences and Arts, Associate Professor of Geology at 2nd and 3rd level study programmes at Postgraduate School ZRC SAZU.


  • Sc. Geology (University of Ljubljana, 1986)
  • Sc. Geology (University of Ljubljana, 1990)
  • D. Geology (University of Ljubljana, 2003)


Research interests

  • Cretaceous and Tertiary stratigraphy, sedimentology palaeoecology, and palaeogeography,
  • Diatom and silicoflagellate paleontology, biostratigraphy and palaeoecology,
  • Quaternary Geology;
  • Geoarchaeology.

Main visiting appointment

  • Visiting lecturer at University of Zagreb, Faculty of Science, Department of Geology, Croatia (2008-2010).


  • Expert Editor on the New Slovenian biographic lexicon
  • Member of Paleontological Society
  • Member of International Associaton of Sedimentologists
  • Member of European Geological Union


PhD mentorships:

  • Tomaž Verbič, 2008: Quaternary sediments, stratigraphy and neotectonics of the eastern Krško basin.
  • Ines Galović, 2009: Middle Miocene (Sarmatian) calcareous nannoplankton, silicoflagellates and diatoms of the soutwestern part of the Paratethys.
  • Anja Kocjančič, since 1. 10. 2020, thesis topic: Sedimentary evolution of Upper Cretaceous basin deposits in the Southern Alps and Dinarides.


Selected publications

  • Tulan, E., Sachsenhofer, R. F., Tari, G. C., Witkowski, J., Tǎmaş, D. M., Horvat, A., Tǎmaş, A. 2020: Hydrocarbon source rock potential and paleoenvironment of lower Miocene diatomites in the Eastern Carpathians Bend Zone (Sibiciu de Sus, Romania). – Geologica Carpathica, 71/5, 424-443.
  • Bohinc, T., Horvat, A., Ocvirk, M., Košir, I. J., Rutnik, K., Trdan, S. 2020: The first evidence of the insecticidal potential of plant powders from invasive alien plants against rice weevil under laboratory conditions. – Applied Sciences, 10/21, 7828,
  • Bohinc, T., Horvat, A., Andrić, G., Pražić Golić, M., Kljajić, P., Trdan, S. 2020: Natural versus synthetic zeolites for controlling the maize weevil (Sitophilus zeamais) – like Messi versus Ronaldo? – Journal of Stored Products Research, 88, 1-9.
  • Goričan, Š., Žibret, L., Košir, A, Kukoč, D. & Horvat, A. 2018: Stratigraphic correlation and structural position of Lower Cretaceous flysch-type deposits in the eastern Southern Alps (NW Slovenia). – International journal of earth sciences, 107-8, 2933-2953.
  • Horvat, A. 2018: Petrology and provenance of the raw material of stone artefacts from the Most na Soči Iron Age settlement. In: Dular, J. & Tecco Hvala, S. (Eds.): Železnodobno naselje Most na Soči. The Iron Age settlement at Most na Soči. Treatises. – Opera Instituti archaeologici Sloveniae, 34, 349-360.
  • Moro, A., Velić, I. Mikuž, V., Horvat, A. 2018: Microfacies characteristics of carbonate cobble from Campanian of Slovenj Gradec (Slovenia) : implications for determining the Fleuryana adriatica De Castro, Drobne and Gušić paleoniche and extending the biostratigraphic range in the Tethyan realm. – Mining-Geological-Petruleum Engineering Bull.,30/42, str. 1-13.
  • Moro, A., Horvat, A., Tomić, V., Sremac, J. & Bermanec, V. 2016: Facies development and paleoecology of rudists and corals: An example of Campanian transgressive sediments from northern Croatia, northeastern Slovenia, and northwestern Bosnia. – Facies,62-19, 18-25.
  • Horvat, A. 2016: Distephanopsis concavusHorvat: a revised silicoflagellate species from the middle miocene of the Central Paratethys. – Geologija, 59/2, 233-241.
  • Moreau, L., Odar, B., Higham, T., Horvat, A., Pirkmajer, D. & Turk P. 2015: Reassessing the Aurignacian of Slovenia. – Journal of Human Evolution, 78, 158-180.
  • Bartol, M., Mikuž, V., Horvat, A. 2014: Palaeontological evidence of communication between the Central Paratethys and the Mediterranean in the late Badenian/early Serravalian. – Palaeogeography, Palaeoclimatology, Palaeoecology; 394; 144-157.
  • Pavšič, J., Horvat, A. 2009: Eocene, Oligocene and Miocene in central and eastern Slovenia. – In: Pleničar, M., Ogorelec, B., Novak, M. (eds.): The Geology of Slovenia, 373-426.
  • Turk, J., Horvat, A. 2009: Sedimentological method for determination of palaeoenvironmental conditions at the Ljubljansko barje, case study Stare gmajne. (In: Velušček, A. (Ed.): The Ljubljansko barje in the 2nd half of the 4th millennium BC) – Opera Instituti archaeologici Sloveniae, 16, 35-48.
  • Horvat, A. 2004: Srednjemiocenske alge Slovenije: paleontologija, stratigrafija, paleontologija, paleobiogeografija. – Middle Miocene siliceous algae of Slovenia: Paleontology, Stratigraphy, Paleoecology, Paleobiogeography. − ZRC Publ., 255 pp., Ljubljana.
  • Horvat, A., Mišič, M. 2004: Mineralogy and sedimentology of diatomaceous sediments in Slovenia. – RMZ – Materials and geoenvironment, 51/4, 2145-2161.
  • Horvat, A. 2003: Upper Badenian diatom paleoecology of the western part of Central Paratethys. – Geologija, 46, 251 – 262.
  • Horvat, A. 2003: Middle Miocene silicoflagellates from the western part of Central Paratethys. – Razpr. 4. razr. SAZU 44, 57 79.