Articles | Volume 6, issue 4
https://doi.org/10.5194/gchron-6-697-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gchron-6-697-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Interpreting cooling dates and histories from laser ablation in situ (U–Th–Sm) ∕ He thermochronometry: a modelling perspective
Christoph Glotzbach
CORRESPONDING AUTHOR
Department of Geosciences, University of Tübingen, Tübingen, 72076, Germany
Todd A. Ehlers
School of Geographical and Earth Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
Department of Geosciences, University of Tübingen, Tübingen, 72076, Germany
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Short summary
The (U–Th–Sm) / He dating method helps understand the cooling history of rocks. Synthetic modelling experiments were conducted to explore factors affecting in situ vs. whole-grain (U–Th) / He dates. In situ dates are often 30 % older than whole-grain dates, whereas very rapid cooling makes helium loss negligible, resulting in similar whole-grain and in situ dates. In addition, in situ data can reveal cooling histories even from a single grain by measuring helium distributions.
The (U–Th–Sm) / He dating method helps understand the cooling history of rocks. Synthetic...