Articles | Volume 4, issue 1
https://doi.org/10.5194/gchron-4-143-2022
© Author(s) 2022. 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-4-143-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Short communication/technical note
| 
22 Mar 2022
Short communication/technical note |
| 22 Mar 2022
| 22 Mar 2022
Short communication: Modeling competing effects of cooling rate, grain size, and radiation damage in low-temperature thermochronometers
David M. Whipp
Department of Geosciences and Geography, University of Helsinki, 00014 University of Helsinki, Helsinki, Finland
Geological Survey of Canada – Atlantic, Natural Resources Canada, Dartmouth, B2Y 4A2, Canada
Isabelle Coutand
Department of Earth and Environmental Sciences, Dalhousie University, Halifax, B3H 4R2, Canada
Richard A. Ketcham
Department of Geological Sciences, Jackson School of Geoscience, University of Texas, Austin, TX 78712, USA
Related authors
Dawn A. Kellett and David M. Whipp
EGUsphere, https://doi.org/10.5194/egusphere-2025-5403, https://doi.org/10.5194/egusphere-2025-5403, 2025
This preprint is open for discussion and under review for Geochronology (GChron).
Short summary
Short summary
Geological processes like erosion, burial, and faulting can influence or perturb heat conditions in the Earth's crust through time, which can complicate our interpretation of the geological significance of rock cooling histories determined from thermochronology. This 1D modeling study quantifies and illustrates the expected relationships between various lithosphere-scale geological processes and resulting thermal histories and thermochronometer ages.
Dawn A. Kellett and David M. Whipp
EGUsphere, https://doi.org/10.5194/egusphere-2025-5403, https://doi.org/10.5194/egusphere-2025-5403, 2025
This preprint is open for discussion and under review for Geochronology (GChron).
Short summary
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Geological processes like erosion, burial, and faulting can influence or perturb heat conditions in the Earth's crust through time, which can complicate our interpretation of the geological significance of rock cooling histories determined from thermochronology. This 1D modeling study quantifies and illustrates the expected relationships between various lithosphere-scale geological processes and resulting thermal histories and thermochronometer ages.
Richard A. Ketcham
Geochronology, 7, 449–458, https://doi.org/10.5194/gchron-7-449-2025, https://doi.org/10.5194/gchron-7-449-2025, 2025
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This technical note develops and demonstrates an improvement in how to calculate the temperatures experienced by rocks as they come from deep in the Earth to the surface due to erosion in mountainous regions that feature significant topographic relief. The solution is fast and flexible, and works even in areas where erosion rates have varied through time. The new method has been added to software used to interpret thermochronologic data to help discern the history of mountain ranges.
Marie Bergelin, Greg Balco, and Richard A. Ketcham
EGUsphere, https://doi.org/10.5194/egusphere-2025-3033, https://doi.org/10.5194/egusphere-2025-3033, 2025
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We developed a faster and simpler way to measure helium gas in rocks to determine how long they have been exposed at Earth's surface. Instead of separating minerals within the rocks by hand, our method uses heat to release gas from specific minerals. This reduces time, cost, and physical work, making it easier to collect large amounts of data when studying landscape change or when only small rock samples are available.
Murat T. Tamer, Ling Chung, Richard A. Ketcham, and Andrew J. W. Gleadow
Geochronology, 7, 45–58, https://doi.org/10.5194/gchron-7-45-2025, https://doi.org/10.5194/gchron-7-45-2025, 2025
Short summary
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We present the first new image-based study to reveal how choices made by different analysts affect the results obtained by fission-track analysis. Participants analyzed an identical image dataset with varying grain quality. Experienced analysts tend to select lower numbers of unsuitable grains and conduct lower numbers of invalid length measurements. Fission-track studies need image data repositories, teaching modules, guidelines, an open science culture, and new approaches for calibration.
Alyssa J. McKanna, Isabel Koran, Blair Schoene, and Richard A. Ketcham
Geochronology, 5, 127–151, https://doi.org/10.5194/gchron-5-127-2023, https://doi.org/10.5194/gchron-5-127-2023, 2023
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Acid leaching is commonly used to remove damaged portions of zircon crystals prior to U–Pb dating. However, a basic understanding of the microstructural processes that occur during leaching is lacking. We present the first 3D view of zircon dissolution based on X-ray computed tomography data acquired before and after acid leaching. These data are paired with images of etched grain surfaces and Raman spectral data. We also reveal exciting opportunities for imaging radiation damage zoning in 3D.
Richard A. Ketcham and Murat T. Tamer
Geochronology, 3, 433–464, https://doi.org/10.5194/gchron-3-433-2021, https://doi.org/10.5194/gchron-3-433-2021, 2021
Short summary
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We introduce a new model of how etching reveals damage tracks left by fissioning atoms, which accounts for variable along-track etching rates. This complete characterization explains many observations, including community difficulty in obtaining consistent track length measurements. It also provides a quantitative basis for optimizing etching procedures, discerning more about how radiation damage anneals, and ultimately deriving more reproducible fission-track ages and thermal histories.
Cited articles
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Short summary
Multi-thermochronometry, in which methods such as (U-Th)/He dating of zircon and apatite and apatite fission track dating are combined, is used to reconstruct rock thermal histories. Our ability to reconstruct thermal histories and interpret the geological significance of measured ages requires modeling. Here we use forward models to explore effects of grain size and chemistry on cooling ages and closure temperatures for the (U-Th)/He decay systems in apatite and zircon.
Multi-thermochronometry, in which methods such as (U-Th)/He dating of zircon and apatite and...
