–––––▼––––– 2021 –––––▼–––––
2021-11-16: New article published in ACS Earth and Space Chemistry: Kinetic oxygen isotope fractionation between water and aqueous OH– during hydroxylation of CO2. We observe a 24‰ offset between the experimental and theoretical-equilbrium isotope fractionation values. We argue that this offset derives from kinetic isotope effects related to the preferential reaction of isotopically light OH– during CO2(aq) hydroxylation. Read the article here.
2021-08-01: As my 2-year postdoc is over, I am moving from the University of Cologne to the University of Göttingen, where I will continue my work on clumped and triple oxygen analyses of carbonates with Prof. Andreas Pack. For my updated contact information, please refer to the Contact page.
2021-06-04: New article published in Paleoceanography and Paleoclimatology: Warm high-elevation mid-latitudes during the Miocene Climatic Optimum: Paleosol clumped isotope temperatures from the Northern Rocky Mountains, USA. Palaeosol carbonate ∆47 records from Montana and Idaho suggest stable (21±2 °C) continental temperatures over the Miocene Climatic Optimum (ca. 17–15 million years ago). Read the open access article here.
2021-06-02: New article published in Geophysical Research Letters: Devils Hole calcite was precipitated at ±1 °C stable aquifer temperatures during the last half million years. In this study, we investigated the Devils Hole caves that provide a reference oxygen isotope time series for North America. Dual clumped isotope thermometry (∆47 and ∆48) reveals that groundwater temperature did not change significantly in the last half-million years. Variations in the oxygen isotope composition of the deposited carbonates solely reflect variations in the oxygen isotope composition of the groundwater. Read the open access article here.
2021-05-13: Results from an in-progress study An experimental constraint on the oxygen isotope fractionation (18O/16O) between water and aqueous hydroxide ion will be presented at the Goldschmidt online conference on 7 July 2021. Read the abstract here.
2021-04-13: New article published in Geochemistry, Geophysics, Geosystems: InterCarb: A community effort to improve inter‐laboratory standardization of the carbonate clumped isotope thermometer using carbonate standards. This community effort, led by Stefano Bernasconi and involving 22 laboratories, provides consensus ∆47 values for carbonate standards and describes best practices for carbonate-based standardisation. Read the open access article here. Read the research spotlight here.
2021-03-09: The article Dual clumped isotope thermometry resolves kinetic biases in carbonate formation temperatures is featured in Nature Communications’ Editor Highlights.
2021-03-03: Results from an in-progress study An experimental constraint on the oxygen isotope fractionation (18O/16O) between water and aqueous hydroxide ion will be presented at the EGU21 conference. Read the abstract here.
–––––▼––––– 2020 –––––▼–––––
2020-12-31: New article published in Földtani Közlöny (in Hungarian): Modern methods of cyclostratigraphy and astrochronology and their applications. Cyclostratigraphy, the science of reading the stratigraphic record of Milankovitch cycles, i.e., climate cycles driven by periodic changes in Earth’s orbital parameters, both provides a means to measure geological time and to reconstruct palaeoclimate. Here, we review the physical drivers of cyclical changes in geological time series, introduce the steps of spectral analyses, and discuss case studies. Read the open access article here (in Hungarian). Ingyenesen olvasható magyarul itt.
2020-08-10: New article published in Nature Communications: Dual clumped isotope thermometry resolves kinetic biases in carbonate formation temperatures. Palaeotemperature reconstructions suffer from inaccuracies related to kinetic fractionations occurring during carbonate mineral growth. Here we show that dual clumped isotope thermometry can identify the origin of these kinetic biases and allows the reconstruction of accurate environmental temperatures. Read the open access article here. Read the press release in English here. Lies die Pressemitteilung auf Deutsch hier.
Dr David Bajnai 