Articles | Volume 5, issue 2
https://doi.org/10.5194/gchron-5-323-2023
© Author(s) 2023. 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-5-323-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note: In situ U–Th–He dating by 4He ∕ 3He laser microprobe analysis
London Geochronology Centre, Department of Earth Sciences,
University College London, Gower Street, London WC1E 6BT,
UK
Yuntao Tian
London Geochronology Centre, Department of Earth Sciences,
University College London, Gower Street, London WC1E 6BT,
UK
Guangdong Provincial Key Laboratory of
Geodynamics and Geohazards, School of Earth Sciences and Engineering,
Sun Yat-sen University, Guangzhou 510275, China
Jae Schwanethal
London Geochronology Centre, Department of Earth Sciences,
University College London, Gower Street, London WC1E 6BT,
UK
Yannick Buret
Department of Earth Sciences, Natural History Museum,
Cromwell Road, London SW7 5BD, UK
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Matthew Fox, Adam G. G. Smith, Pieter Vermeesch, Kerry Gallagher, and Andrew Carter
Geochronology Discuss., https://doi.org/10.5194/gchron-2022-23, https://doi.org/10.5194/gchron-2022-23, 2022
Publication in GChron not foreseen
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The Great Unconformity represents an enormous amount of time lost from the sedimentary record. Its origin is debated, in part, due to different approaches used to interpret zircon (U–Th)/He ages. This thermochronometric system is ideal for this problem because the temperature sensitivity varies according to radiation damage. Here we explore the uncertainty associated with the radiation damage model and show how this limits our ability to resolve the origin of the Great Unconformity.
Pieter Vermeesch
Geochronology, 4, 561–576, https://doi.org/10.5194/gchron-4-561-2022, https://doi.org/10.5194/gchron-4-561-2022, 2022
Short summary
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compositional data, which means that the relative abundances of 204Pb, 206Pb, 207Pb, and 238Pb are processed within a tetrahedral data space or
simplex. The new method is implemented in an eponymous computer programme that is compatible with the two dominant types of SIMS instruments.
Yang Li and Pieter Vermeesch
Geochronology, 3, 415–420, https://doi.org/10.5194/gchron-3-415-2021, https://doi.org/10.5194/gchron-3-415-2021, 2021
Short summary
Short summary
A conventional isochron is a straight-line fit to two sets of isotopic ratios, D/d and P/d, where P is the radioactive parent, D is the radiogenic daughter, and d is a second isotope of the daughter element. The slope of this line is proportional to the age of the system. An inverse isochron is a linear fit through d/D and P/D. The horizontal intercept of this line is inversely proportional to the age. The latter approach is preferred when d<D, which is the case in Re–Os and K–Ca geochronology.
Pieter Vermeesch
Geochronology, 3, 247–257, https://doi.org/10.5194/gchron-3-247-2021, https://doi.org/10.5194/gchron-3-247-2021, 2021
Short summary
Short summary
This paper shows that the current practice of filtering discordant U–Pb data based on the relative difference between the 206Pb/238U and 207Pb/206Pb ages is just one of several possible approaches to the problem and demonstrably not the best one. An alternative approach is to define discordance in terms of isotopic composition, as a log ratio distance between the measurement and the concordia line. Application to real data indicates that this reduces the positive bias of filtered age spectra.
Cited articles
Boyce, J. W., Hodges, K. V., Olszewski, W. J., Jercinovic, M. J.,
Carpenter, B. D., and Reiners, P. W.: Laser microprobe (U-Th)/He
geochronology, Geochim. Cosmochim. Ac., 70, 3031–3039,
https://doi.org/10.1016/j.gca.2006.03.019, 2006. a, b
Boyce, J. W., Hodges, K. V., King, D., Crowley, J. L., Jercinovic,
M., Chatterjee, N., Bowring, S. A., and Searle, M.: Improved
confidence in (U-Th) He thermochronology using the laser microprobe: An
example from a Pleistocene leucogranite, Nanga Parbat, Pakistan,
Geochem. Geophy. Geosy., 10, Q0AA01, https://doi.org/10.1029/2009GC002497, 2009. a
Brennan, C. J., Stockli, D. F., and Patterson, D. B.: Zircon 4He/3He
fractional loss step-heating and characterization of parent nuclide
distribution, Chem. Geol., 549, 119692, https://doi.org/10.106/j.chemgeo.2020.119692, 2020. a
Colleps, C., van der Beek, P., Denker, A., Amalberti, J., Dittwald, A.,
Bundesmann, J., and Bernard, M.: Improving the Efficiency of Proton
Irradiations for 4He 3He Thermochronology, AGU Fall Meeting
12–16 December 2022, Chicago, IL, USA, 2022AGUFMEP22E1381C, EP22E–1381, 2022. a
Danišík, M., McInnes, B. I., Kirkland, C. L., McDonald, B. J.,
Evans, N. J., and Becker, T.: Seeing is believing: Visualization of He
distribution in zircon and implications for thermal history reconstruction on
single crystals, Sci. Adv., 3, e1601121, https://doi.org/10.1126/sciadv.1601121, 2017. a
Farley, K. A., Wolf, R. A., and Silver, L. T.: The effects of long
alpha-stopping distances on (U-Th) He ages, Geochim. Cosmochim. Ac.,
60, 4223–4229, https://doi.org/10.1016/S0016-7037(96)00193-7, 1996. a
House, M. A., Farley, K. A., and Stockli, D.: Helium chronometry of
apatite and titanite using Nd-YAG laser heating, Earth Planet. Sc.
Lett., 183, 365–368, https://doi.org/10.1016/S0012-821X(00)00286-7, 2000. a
Hurford, A. J. and Green, P. F.: The zeta age calibration of fission-track
dating, Chem. Geol., 41, 285–317,
https://doi.org/10.1016/S0009-2541(83)80026-6, 1983. a
Jackson, S. E., Pearson, N. J., Griffin, W. L., and Belousova, E. A.: The
application of laser ablation-inductively coupled plasma-mass spectrometry to
in situ U–Pb zircon geochronology, Chem. Geol., 211, 47–69,
https://doi.org/10.1016/j.chemgeo.2004.06.017, 2004. a
Ketcham, R. A., Gautheron, C., and Tassan-Got, L.: Accounting for long
alpha-particle stopping distances in (U–Th–Sm) He geochronology: refinement
of the baseline case, Geochim. Cosmochim. Ac., 75, 7779–7791, 2011. a
Kuiper, K. F., Deino, A., Hilgen, F. J., Krijgsman, W., Renne, P. R.,
and Wijbrans, J. R.: Synchronizing Rock Clocks of Earth History, Science,
320, 500–504, https://doi.org/10.1126/science.1154339, 2008. a
Merrihue, C. and Turner, G.: Potassium-argon dating by activation with fast
neutrons, J. Geophys. Res., 71, 2852–2857, 1966. a
Pastore, G., Baird, T., Vermeesch, P., Bristow, C., Resentini, A., and
Garzanti, E.: Provenance and recycling of Sahara Desert sand, Earth-Sci.
Rev., 216, 103606, https://doi.org/10.1016/j.earscirev.2021.103606, 2021. a
Reiners, P. W., Campbell, I. H., Nicolescu, S., Allen, C. M., Hourigan, J. K.,
Garver, J. I., Mattinson, J. M., and Cowan, D. S.: (U-Th) (He-Pb) double
dating of detrital zircons, Am. J. Sci., 305, 259–311,
https://doi.org/10.2475/ajs.305.4.259, 2005. a
Schwanethal, J.: Minimising 12C3+ interference on 4He+
measurements in a noble gas mass spectrometer, J. Anal. Atom.
Spectrom., 30, 1400–1404, 2015. a
Shuster, D. L., Farley, K. A., Sisterson, J. M., and Burnett, D. S.:
Quantifying the diffusion kinetics and spatial distributions of radiogenic
4He in minerals containing proton-induced 3He, Earth Planet.
Sc. Lett., 217, 19–32, https://doi.org/10.1016/S0012-821X(03)00594-6, 2004. a, b
Tian, Y., Vermeesch, P., Danišík, M., Condon, D. J., Chen, W., Kohn,
B., Schwanethal, J., and Rittner, M.: LGC-1: A zircon reference material for
in-situ (U-Th) He dating, Chem. Geol., 454, 80–92, https://doi.org/10.1016/j.chemgeo.2017.02.026, 2017.
a, b
Tripathy-Lang, A., Hodges, K. V., Monteleone, B. D., and Soest, M. C.: Laser
(U-Th) He thermochronology of detrital zircons as a tool for studying surface
processes in modern catchments, J. Geophys. Res.-Earth, 118, 1333–1341, 2013. a
Tripathy-Lang, A., Fox, M., and Shuster, D. L.: Zircon 4He 3He
thermochronometry, Geochim. Cosmochim. Ac., 166, 1–14, 2015. a
van Soest, M. C., Monteleone, B. D., Hodges, K. V., and Boyce, J. W.:
Laser depth profiling studies of helium diffusion in Durango fluorapatite,
Geochim. Cosmochim. Ac., 75, 2409–2419, 2011. a
Vermeesch, P.: Three new ways to calculate average (U-Th) He ages,
Chem. Geol., 249, 339–347, 2008. a
Vermeesch, P.: HelioPlot, and the treatment of overdispersed (U-Th-Sm) He
data, Chem. Geol., 271, 108–111,
https://doi.org/10.1016/j.chemgeo.2010.01.002, 2010. a, b
Vermeesch, P.: Logratio table of in-situ U-Th-4He/3He dated Fish Canyon zircon, Zenodo [data set], https://doi.org/10.5281/zenodo.8005223, 2023. a
Short summary
The U–Th–He method is a technique to determine the cooling history of minerals. Traditional approaches to U–Th–He dating are time-consuming and require handling strong acids and radioactive solutions. This paper presents an alternative approach in which samples are irradiated with protons and subsequently analysed by laser ablation mass spectrometry. Unlike previous in situ U–Th–He dating attempts, the new method does not require any absolute concentration measurements of U, Th, or He.
The U–Th–He method is a technique to determine the cooling history of minerals. Traditional...