Investigation of Travertines and Tufas

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Contact person:

Sándor Kele, PhD

Freshwater limestones (travertines, surface and cave tufas) belong to the group of continental carbonates and are common formations in the Carpathian Basin. Owing to their temporal distribution, they are suitable for climate reconstruction over several hundred thousand years. In addition to reflecting local precipitation conditions and enabling the reconstruction of depositional environments, they also preserve signals of global scale climate change. The study of modern, actively forming freshwater carbonates and the carbonate precipitating waters is equally indispensable, as a better understanding of the factors influencing isotope fractionation processes between calcite/aragonite and water provides crucial information for stable and clumped isotope paleotemperature calculations.

Main analytical methods

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• Stable isotope measurements (δ¹³C, δ¹⁸O) – for determining carbonate precipitation temperature and reconstructing paleovegetation. (HUN REN CSFK Institute for Geological and Geochemical Research)
• Clumped isotope (Δ₄₇) analysis – for determining carbonate formation temperature (HUN REN ATOMKI)
• U–Th (uranium–thorium) dating – for absolute age determination up to 600,000 years (HUN REN ATOMKI)

Ongoing research projects

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• High resolution isotope chronostratigraphic investigation of freshwater limestone deposits from Tivoli (Italy) and Tata (Hungary). Bilateral international research project No. NKM 2022 37 (2023–2025) between the IGGR (MTA Centre of Excellence) and the Italian CNR. Hungarian Project Leader: Sándor Kele.
• Determination of the age and precipitation temperature of the freshwater limestone (tufa) that hosts the Paleolithic site and Homo heidelbergensis remains at Vértesszőlős.
• Complex geochemical and sedimentological study of freshwater limestones and tufas from Slovakia and Transylvania.
• Stable isotope geochemical investigation of the Kocabaş travertine occurrence (Denizli Basin, Western Turkey), which contains Homo erectus remains. (in collaboration with the Max Planck Institute).
• Investigation of the influence of microbial processes, bacteria, and viruses on carbonate precipitation in modern travertines (Egerszalók). (in collaboration with Mirosław Słowakiewicz, University of Warsaw).
• Complex structural geological and geochemical study of hydrothermal travertine formations in Western Anatolia (Turkey). (in collaboration with Andrea Brogi, University of Bari).
• Study of the formation and crystallization processes of carbonate cements in the basaltic host rocks of the Sverrefjellet volcano, Svalbard, Norway. (in collaboration with Andrea Pierozzi, Trinity College Dublin).