Articles | Volume 6, issue 4
https://doi.org/10.5194/gchron-6-665-2024
© 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-6-665-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Dec 2024
Research article |
| 17 Dec 2024
| 17 Dec 2024
Zircon luminescence dating revisited
Christoph Schmidt
CORRESPONDING AUTHOR
Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, 1015, Switzerland
Théo Halter
Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, 1015, Switzerland
Paul R. Hanson
Conservation and Survey Division, School of Natural Resources, University of Nebraska–Lincoln, Lincoln, NE, 68583, United States of America
Alexey Ulianov
Institute of Earth Sciences, University of Lausanne, Lausanne, 1015, Switzerland
Benita Putlitz
Institute of Earth Sciences, University of Lausanne, Lausanne, 1015, Switzerland
Georgina E. King
Institute of Earth Surface Dynamics, University of Lausanne, Lausanne, 1015, Switzerland
Sebastian Kreutzer
Institute of Geography, Heidelberg University, 69120 Heidelberg, Germany
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Mathieu Bosq, Sebastian Kreutzer, Pascal Bertran, Philippe Lanos, Philippe Dufresne, and Christoph Schmidt
Earth Syst. Sci. Data, 15, 4689–4711, https://doi.org/10.5194/essd-15-4689-2023, https://doi.org/10.5194/essd-15-4689-2023, 2023
Short summary
Short summary
During the last glacial period, cold conditions associated with changes in atmospheric circulation resulted in the deposition of widespread loess. It seems that the phases of loess accumulation were not strictly synchronous. To test this hypothesis, the chronology of loess deposition in different regions of Europe was studied by recalculating 1423 luminescence ages in a database. Our study discusses the link between the main loess sedimentation phases and the maximal advance of glaciers.
Dominik Faust, Sebastian Kreutzer, Yesmine Trigui, Maximilian Pachtmann, Georg Mettig, Moncef Bouaziz, Jose Manuel Recio Espejo, Fernando Diaz del Olmo, Christoph Schmidt, Tobias Lauer, Zeljko Rezek, Alexander Fülling, and Sascha Meszner
E&G Quaternary Sci. J., 69, 55–58, https://doi.org/10.5194/egqsj-69-55-2020, https://doi.org/10.5194/egqsj-69-55-2020, 2020
Annette Kadereit, Sebastian Kreutzer, Christoph Schmidt, and Regina DeWitt
Geochronology Discuss., https://doi.org/10.5194/gchron-2020-3, https://doi.org/10.5194/gchron-2020-3, 2020
Preprint withdrawn
Sebastian Kreutzer, Loïc Martin, Didier Miallier, and Norbert Mercier
Geochronology Discuss., https://doi.org/10.5194/gchron-2024-31, https://doi.org/10.5194/gchron-2024-31, 2024
Preprint under review for GChron
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Accurate readings on the environmental gamma dose rate are important. Portable gamma-ray detectors, such as NaI or LaBr3-based, are easy to handle and affordable. Limited information on alternatives, like CZT (Cadmium Zinc Telluride) detectors is available. We tested CZT detectors and found them suitable for in-field deployment. We used simulations and field tests to evaluate the optimal energy threshold for direct dose rate readings, making the CZT system a reliable alternative.
Veronica Peverelli, Alfons Berger, Martin Wille, Thomas Pettke, Benita Putlitz, Andreas Mulch, Edwin Gnos, and Marco Herwegh
Eur. J. Mineral., 36, 879–898, https://doi.org/10.5194/ejm-36-879-2024, https://doi.org/10.5194/ejm-36-879-2024, 2024
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We used U–Pb dating and Pb–Sr–O–H isotopes of hydrothermal epidote to characterize fluid circulation in the Aar Massif (central Swiss Alps). Our data support the hypothesis that Permian fluids exploited syn-rift extensional faults. In the Miocene during the Alpine orogeny, fluid sources were meteoric, sedimentary, and/or metamorphic water. Likely, Miocene shear zones were exploited for fluid circulation, with implications for the Sr isotope budget of the granitoids.
Mariana Sontag-González, Raju Kumar, Jean-Luc Schwenninger, Juergen Thieme, Sebastian Kreutzer, and Marine Frouin
Geochronology, 6, 77–88, https://doi.org/10.5194/gchron-6-77-2024, https://doi.org/10.5194/gchron-6-77-2024, 2024
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This is a preliminary study using a synchrotron light source to generate elemental maps, incorporating oxidation states, with a spatial resolution of <1 µm for individual grains within the K-feldspar density fraction. The elemental fingerprint characterizing grains with a signal suitable for infrared radiofluorescence dating reveals high levels of K, Pb, and Ba coupled with low levels of Fe and Ca. In contrast, grains exhibiting higher proportions of Fe and Ca produce an odd signal shape.
Nora Pfaffner, Annette Kadereit, Volker Karius, Thomas Kolb, Sebastian Kreutzer, and Daniela Sauer
E&G Quaternary Sci. J., 73, 1–22, https://doi.org/10.5194/egqsj-73-1-2024, https://doi.org/10.5194/egqsj-73-1-2024, 2024
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We present results of the Baix loess–palaeosol sequence, SE France. Reconstructed intense soil formation under warm, moist conditions before and into the last ice age and less intense soil formations in warm (temporarily moist) phases during the generally cold, dry ice age were validated with laboratory and dating techniques. This is particularly relevant as Baix is located in the temperate–Mediterranean climate transition zone, a sensitive zone that is susceptible to future climate changes.
Mathieu Bosq, Sebastian Kreutzer, Pascal Bertran, Philippe Lanos, Philippe Dufresne, and Christoph Schmidt
Earth Syst. Sci. Data, 15, 4689–4711, https://doi.org/10.5194/essd-15-4689-2023, https://doi.org/10.5194/essd-15-4689-2023, 2023
Short summary
Short summary
During the last glacial period, cold conditions associated with changes in atmospheric circulation resulted in the deposition of widespread loess. It seems that the phases of loess accumulation were not strictly synchronous. To test this hypothesis, the chronology of loess deposition in different regions of Europe was studied by recalculating 1423 luminescence ages in a database. Our study discusses the link between the main loess sedimentation phases and the maximal advance of glaciers.
Sebastian Kreutzer, Steve Grehl, Michael Höhne, Oliver Simmank, Kay Dornich, Grzegorz Adamiec, Christoph Burow, Helen M. Roberts, and Geoff A. T. Duller
Geochronology, 5, 271–284, https://doi.org/10.5194/gchron-5-271-2023, https://doi.org/10.5194/gchron-5-271-2023, 2023
Short summary
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The concept of open data has become the modern science meme. Funding bodies and publishers support open data. However, the open data mandate frequently encounters technical obstacles, such as a lack of a suitable data format for data sharing and long-term data preservation. Such issues are often community-specific and demand community-tailored solutions. We propose a new human-readable data format for data exchange and long-term preservation of luminescence data called XLUM.
Melanie Bartz, Jasquelin Peña, Stéphanie Grand, and Georgina E. King
Geochronology, 5, 51–64, https://doi.org/10.5194/gchron-5-51-2023, https://doi.org/10.5194/gchron-5-51-2023, 2023
Short summary
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Chemical weathering alters the chemical composition of mineral grains, and it follows that luminescence dating signals may also be progressively modified. We artificially weathered feldspar samples under different chemical conditions to understand the effect of feldspar partial dissolution on their luminescence properties. Only minor changes were observed on luminescence dating properties, implying that chemical alteration of feldspar surfaces may not affect luminescence dating signals.
Joanne Elkadi, Benjamin Lehmann, Georgina E. King, Olivia Steinemann, Susan Ivy-Ochs, Marcus Christl, and Frédéric Herman
Earth Surf. Dynam., 10, 909–928, https://doi.org/10.5194/esurf-10-909-2022, https://doi.org/10.5194/esurf-10-909-2022, 2022
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Glacial and non-glacial processes have left a strong imprint on the landscape of the European Alps, but further research is needed to better understand their long-term effects. We apply a new technique combining two methods for bedrock surface dating to calculate post-glacier erosion rates next to a Swiss glacier. Interestingly, the results suggest non-glacial erosion rates are higher than previously thought, but glacial erosion remains the most influential on landscape evolution.
Michael Dietze, Sebastian Kreutzer, Margret C. Fuchs, and Sascha Meszner
Geochronology, 4, 323–338, https://doi.org/10.5194/gchron-4-323-2022, https://doi.org/10.5194/gchron-4-323-2022, 2022
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The R package sandbox is a collection of functions that allow the creation, sampling and analysis of fully virtual sediment sections, like having a virtual twin of real-world deposits. This article introduces the concept, features, and workflows required to use sandbox. It shows how a real-world sediment section can be mapped into the model and subsequently addresses a series of theoretical and practical questions, exploiting the flexibility of the model framework.
Norbert Mercier, Jean-Michel Galharret, Chantal Tribolo, Sebastian Kreutzer, and Anne Philippe
Geochronology, 4, 297–310, https://doi.org/10.5194/gchron-4-297-2022, https://doi.org/10.5194/gchron-4-297-2022, 2022
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Dosimetric dating methods based on the analysis of luminescence signals emitted by granular minerals extracted from sedimentary deposits now play an important role in the study of the Quaternary. Here we propose a new approach in which the age of the deposit is calculated by combining the equivalent dose and dose-rate distributions. The underlying Bayesian mathematical model and its implementation via an R code are provided, together with the results obtained for a finite set of configurations.
Barbara Mauz, Loïc Martin, Michael Discher, Chantal Tribolo, Sebastian Kreutzer, Chiara Bahl, Andreas Lang, and Nobert Mercier
Geochronology, 3, 371–381, https://doi.org/10.5194/gchron-3-371-2021, https://doi.org/10.5194/gchron-3-371-2021, 2021
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Luminescence dating requires irradiating the sample in the laboratory. Here, we address some concerns about the reliability of the calibration procedure that have been published recently. We found that the interplay between geometrical parameters such as grain size and aliquot size impacts the calibration value more than previously thought. The results of our study are robust and allow us to recommend an improved calibration procedure in order to enhance the reliability of the calibration value.
Dirk Mittelstraß and Sebastian Kreutzer
Geochronology, 3, 299–319, https://doi.org/10.5194/gchron-3-299-2021, https://doi.org/10.5194/gchron-3-299-2021, 2021
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Our contribution enhances the infrared radiofluorescence dating technique, used to determine the last sunlight exposure of potassium feldspars in a range of about 600 to 600 000 years backwards. We recorded radiofluorescence images of fine sands and processed them with tailored open-source software to obtain ages from single grains. Finally, we tested our new method successfully on two natural sediment samples. Studies in Earth science will benefit from improved age accuracy and new insights.
Guillaume Guérin, Christelle Lahaye, Maryam Heydari, Martin Autzen, Jan-Pieter Buylaert, Pierre Guibert, Mayank Jain, Sebastian Kreutzer, Brice Lebrun, Andrew S. Murray, Kristina J. Thomsen, Petra Urbanova, and Anne Philippe
Geochronology, 3, 229–245, https://doi.org/10.5194/gchron-3-229-2021, https://doi.org/10.5194/gchron-3-229-2021, 2021
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This paper demonstrates how to model optically stimulated luminescence (OSL) and radiocarbon ages in a Bayesian framework, using a dedicated software tool called BayLum. We show the effect of stratigraphic constraints, of modelling the covariance of ages when the same equipment is used for a series of OSL samples, and of including independent ages on a chronological inference. The improvement in chronological resolution is significant.
Dominik Brill, Simon Matthias May, Nadia Mhammdi, Georgina King, Benjamin Lehmann, Christoph Burow, Dennis Wolf, Anja Zander, and Helmut Brückner
Earth Surf. Dynam., 9, 205–234, https://doi.org/10.5194/esurf-9-205-2021, https://doi.org/10.5194/esurf-9-205-2021, 2021
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Wave-transported boulders are important records for storm and tsunami impact over geological timescales. Their use for hazard assessment requires chronological information. We investigated the potential of a new dating technique, luminescence rock surface exposure dating, for estimating transport ages of wave-emplaced boulders. Our results indicate that the new approach may provide chronological information on decadal to millennial timescales for boulders not datable by any other method so far.
Rabiul H. Biswas, Frédéric Herman, Georgina E. King, Benjamin Lehmann, and Ashok K. Singhvi
Clim. Past, 16, 2075–2093, https://doi.org/10.5194/cp-16-2075-2020, https://doi.org/10.5194/cp-16-2075-2020, 2020
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A new approach to reconstruct the temporal variation of rock surface temperature using the thermoluminescence (TL) of feldspar is introduced. Multiple TL signals or thermometers in the range of 210 to 250 °C are sensitive to typical surface temperature fluctuations and can be used to constrain thermal histories of rocks over ~50 kyr. We show that it is possible to recover thermal histories of rocks using inverse modeling and with δ18O anomalies as a priori information.
Dominik Faust, Sebastian Kreutzer, Yesmine Trigui, Maximilian Pachtmann, Georg Mettig, Moncef Bouaziz, Jose Manuel Recio Espejo, Fernando Diaz del Olmo, Christoph Schmidt, Tobias Lauer, Zeljko Rezek, Alexander Fülling, and Sascha Meszner
E&G Quaternary Sci. J., 69, 55–58, https://doi.org/10.5194/egqsj-69-55-2020, https://doi.org/10.5194/egqsj-69-55-2020, 2020
Vincent Mouchi, Camille Godbillot, Vianney Forest, Alexey Ulianov, Franck Lartaud, Marc de Rafélis, Laurent Emmanuel, and Eric P. Verrecchia
Biogeosciences, 17, 2205–2217, https://doi.org/10.5194/bg-17-2205-2020, https://doi.org/10.5194/bg-17-2205-2020, 2020
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Rare earth elements (REEs) in coastal seawater are included in bivalve shells during growth, and a regional fingerprint can be defined for provenance and environmental monitoring studies. We present a large dataset of REE abundances from oysters from six locations in France. The cupped oyster can be discriminated from one locality to another, but this is not the case for the flat oyster. Therefore, provenance studies using bivalve shells based on REEs are not adapted for the flat oyster.
Annette Kadereit, Sebastian Kreutzer, Christoph Schmidt, and Regina DeWitt
Geochronology Discuss., https://doi.org/10.5194/gchron-2020-3, https://doi.org/10.5194/gchron-2020-3, 2020
Preprint withdrawn
Georgina E. King, Sumiko Tsukamoto, Frédéric Herman, Rabiul H. Biswas, Shigeru Sueoka, and Takahiro Tagami
Geochronology, 2, 1–15, https://doi.org/10.5194/gchron-2-1-2020, https://doi.org/10.5194/gchron-2-1-2020, 2020
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Rates of landscape evolution over the past million years are difficult to quantify. This study develops a technique which is able to measure changes in rock cooling rates (related to landscape evolution) over this timescale. The technique is based on the electron spin resonance dating of quartz minerals. Measurement protocols and new numerical models are proposed that describe these data, allowing for their translation into rock cooling rates.
Benjamin Lehmann, Frédéric Herman, Pierre G. Valla, Georgina E. King, and Rabiul H. Biswas
Earth Surf. Dynam., 7, 633–662, https://doi.org/10.5194/esurf-7-633-2019, https://doi.org/10.5194/esurf-7-633-2019, 2019
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Assessing the impact of glaciation at the Earth's surface requires simultaneous quantification of the impact of climate variability on past glacier fluctuations and on bedrock erosion. Here we present a new approach for evaluating post-glacial bedrock surface erosion in mountainous environments by combining two different surface exposure dating methods. This approach can be used to estimate how bedrock erosion rates vary spatially and temporally since glacier retreat in an alpine environment.
Related subject area
Luminescence dating
A direct comparison of single grain and multi-grain aliquot luminescence dating of feldspars from colluvial deposits in KwaZulu-Natal, South Africa
Short communication: Synchrotron-based elemental mapping of single grains to investigate variable infrared-radiofluorescence emissions for luminescence dating
Insight into the dynamics of a long-runout mass movement using single-grain feldspar luminescence in the Pokhara Valley, Nepal
Technical note: Darkroom lighting for luminescence dating laboratory
Differential bleaching of quartz and feldspar luminescence signals under high-turbidity conditions
XLUM: an open data format for exchange and long-term preservation of luminescence data
Potential impacts of chemical weathering on feldspar luminescence dating properties
Attenuation of beta radiation in granular matrices: implications for trapped-charge dating
Luminescence age calculation through Bayesian convolution of equivalent dose and dose-rate distributions: the De_Dr model
Technical note: Quantifying uranium-series disequilibrium in natural samples for dosimetric dating – Part 1: gamma spectrometry
The μDose system: determination of environmental dose rates by combined alpha and beta counting – performance tests and practical experiences
Erosion rates in a wet, temperate climate derived from rock luminescence techniques
Technical note: On the reliability of laboratory beta-source calibration for luminescence dating
Spatially resolved infrared radiofluorescence: single-grain K-feldspar dating using CCD imaging
Towards an improvement of optically stimulated luminescence (OSL) age uncertainties: modelling OSL ages with systematic errors, stratigraphic constraints and radiocarbon ages using the R package BayLum
Luminescence properties and dating of glacial to periglacial sediments from northern Switzerland
Extended-range luminescence dating of quartz and alkali feldspar from aeolian sediments in the eastern Mediterranean
Svenja Riedesel, Guillaume Guérin, Kristina J. Thomsen, Mariana Sontag-González, Matthias Blessing, Greg A. Botha, Max Hellers, Gunther Möller, Andreas Peffeköver, Christian Sommer, Anja Zander, and Manuel Will
Geochronology Discuss., https://doi.org/10.5194/gchron-2024-19, https://doi.org/10.5194/gchron-2024-19, 2024
Revised manuscript accepted for GChron
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We apply luminescence dating of feldspars to establish a geochronological framework for the sequence of accretionary hillslope deposition at Jojosi, which contain important archaeological artefacts. We test and evaluate four different dose models and their applicability to single grain and multi-grain data sets containing up to 67 % saturated grains. Our results constrain erosional and depositional processes from 100–700 ka, and human occupation of the area in the early MIS 5 and late MIS 6.
Mariana Sontag-González, Raju Kumar, Jean-Luc Schwenninger, Juergen Thieme, Sebastian Kreutzer, and Marine Frouin
Geochronology, 6, 77–88, https://doi.org/10.5194/gchron-6-77-2024, https://doi.org/10.5194/gchron-6-77-2024, 2024
Short summary
Short summary
This is a preliminary study using a synchrotron light source to generate elemental maps, incorporating oxidation states, with a spatial resolution of <1 µm for individual grains within the K-feldspar density fraction. The elemental fingerprint characterizing grains with a signal suitable for infrared radiofluorescence dating reveals high levels of K, Pb, and Ba coupled with low levels of Fe and Ca. In contrast, grains exhibiting higher proportions of Fe and Ca produce an odd signal shape.
Anna-Maartje de Boer, Wolfgang Schwanghart, Jürgen Mey, Basanta Raj Adhikari, and Tony Reimann
Geochronology, 6, 53–70, https://doi.org/10.5194/gchron-6-53-2024, https://doi.org/10.5194/gchron-6-53-2024, 2024
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This study tested the application of single-grain feldspar luminescence for dating and reconstructing sediment dynamics of an extreme mass movement event in the Himalayan mountain range. Our analysis revealed that feldspar signals can be used to estimate the age range of the deposits if the youngest subpopulation from a sample is retrieved. The absence of clear spatial relationships with our bleaching proxies suggests that sediments were transported under extremely limited light exposure.
Marine Frouin, Taylor Grandfield, William Huebsch, and Owen Evans
Geochronology, 5, 405–412, https://doi.org/10.5194/gchron-5-405-2023, https://doi.org/10.5194/gchron-5-405-2023, 2023
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Here, we present the lighting setting implemented in the new Luminescence Dating Research Laboratory at Stony Brook University, USA. First, we performed spectral measurements on different light sources and filters. Then, we measured the loss of dose in quartz and feldspar samples when exposed to various light sources and durations. Finally, we conclude that our lighting setting is suitable for a luminescence darkroom laboratory; it is simple, inexpensive to build, and durable.
Jürgen Mey, Wolfgang Schwanghart, Anna-Maartje de Boer, and Tony Reimann
Geochronology, 5, 377–389, https://doi.org/10.5194/gchron-5-377-2023, https://doi.org/10.5194/gchron-5-377-2023, 2023
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This study presents the results of an outdoor flume experiment to evaluate the effect of turbidity on the bleaching of fluvially transported sediment. Our main conclusions are that even small amounts of sediment lead to a substantial change in the intensity and frequency distribution of light within the suspension and that flow turbulence is an important prerequisite for bleaching grains during transport.
Sebastian Kreutzer, Steve Grehl, Michael Höhne, Oliver Simmank, Kay Dornich, Grzegorz Adamiec, Christoph Burow, Helen M. Roberts, and Geoff A. T. Duller
Geochronology, 5, 271–284, https://doi.org/10.5194/gchron-5-271-2023, https://doi.org/10.5194/gchron-5-271-2023, 2023
Short summary
Short summary
The concept of open data has become the modern science meme. Funding bodies and publishers support open data. However, the open data mandate frequently encounters technical obstacles, such as a lack of a suitable data format for data sharing and long-term data preservation. Such issues are often community-specific and demand community-tailored solutions. We propose a new human-readable data format for data exchange and long-term preservation of luminescence data called XLUM.
Melanie Bartz, Jasquelin Peña, Stéphanie Grand, and Georgina E. King
Geochronology, 5, 51–64, https://doi.org/10.5194/gchron-5-51-2023, https://doi.org/10.5194/gchron-5-51-2023, 2023
Short summary
Short summary
Chemical weathering alters the chemical composition of mineral grains, and it follows that luminescence dating signals may also be progressively modified. We artificially weathered feldspar samples under different chemical conditions to understand the effect of feldspar partial dissolution on their luminescence properties. Only minor changes were observed on luminescence dating properties, implying that chemical alteration of feldspar surfaces may not affect luminescence dating signals.
Alastair C. Cunningham, Jan-Pieter Buylaert, and Andrew S. Murray
Geochronology, 4, 517–531, https://doi.org/10.5194/gchron-4-517-2022, https://doi.org/10.5194/gchron-4-517-2022, 2022
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Mineral grains within sediment or rock absorb a radiation dose from the decay of radionuclides in the host matrix. For the beta dose component, the estimated dose rate must be adjusted for the attenuation of beta particles within the mineral grains. We show here that the mean dose rate to dosimeter grains in a granular matrix is dependent on the grain-size distributions of the source grains, the bulk sediment, and the grain size of the dosimeters.
Norbert Mercier, Jean-Michel Galharret, Chantal Tribolo, Sebastian Kreutzer, and Anne Philippe
Geochronology, 4, 297–310, https://doi.org/10.5194/gchron-4-297-2022, https://doi.org/10.5194/gchron-4-297-2022, 2022
Short summary
Short summary
Dosimetric dating methods based on the analysis of luminescence signals emitted by granular minerals extracted from sedimentary deposits now play an important role in the study of the Quaternary. Here we propose a new approach in which the age of the deposit is calculated by combining the equivalent dose and dose-rate distributions. The underlying Bayesian mathematical model and its implementation via an R code are provided, together with the results obtained for a finite set of configurations.
Barbara Mauz, Paul J. Nolan, and Peter G. Appleby
Geochronology, 4, 213–225, https://doi.org/10.5194/gchron-4-213-2022, https://doi.org/10.5194/gchron-4-213-2022, 2022
Short summary
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It is of critical importance to dosimetric dating techniques that the quantity of the radiation dose is estimated accurately. Here we describe gamma spectrometry in terms of instrument, measurement procedures, and data analyses required for estimating parent nuclide activities. The description includes analytical procedures required to generate data with sufficient accuracy and precision for samples in secular equilibrium. We also outline procedures required to quantify disequilibrium.
Thomas Kolb, Konrad Tudyka, Annette Kadereit, Johanna Lomax, Grzegorz Poręba, Anja Zander, Lars Zipf, and Markus Fuchs
Geochronology, 4, 1–31, https://doi.org/10.5194/gchron-4-1-2022, https://doi.org/10.5194/gchron-4-1-2022, 2022
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The µDose system is an innovative analytical instrument developed for the cost- and time-efficient determination of environmental radionuclide concentrations required for the calculation of sedimentation ages in palaeo-environmental and geo-archaeological research. The results of our study suggest that accuracy and precision of µDose measurements are comparable to those of well-established methods and that the new approach shows the potential to become a standard tool in environmental dosimetry.
Rachel K. Smedley, David Small, Richard S. Jones, Stephen Brough, Jennifer Bradley, and Geraint T. H. Jenkins
Geochronology, 3, 525–543, https://doi.org/10.5194/gchron-3-525-2021, https://doi.org/10.5194/gchron-3-525-2021, 2021
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We apply new rock luminescence techniques to a well-constrained scenario of the Beinn Alligin rock avalanche, NW Scotland. We measure accurate erosion rates consistent with independently derived rates and reveal a transient state of erosion over the last ~4000 years in the wet, temperate climate of NW Scotland. This study shows that the new luminescence erosion-meter has huge potential for inferring erosion rates on sub-millennial scales, which is currently impossible with existing techniques.
Barbara Mauz, Loïc Martin, Michael Discher, Chantal Tribolo, Sebastian Kreutzer, Chiara Bahl, Andreas Lang, and Nobert Mercier
Geochronology, 3, 371–381, https://doi.org/10.5194/gchron-3-371-2021, https://doi.org/10.5194/gchron-3-371-2021, 2021
Short summary
Short summary
Luminescence dating requires irradiating the sample in the laboratory. Here, we address some concerns about the reliability of the calibration procedure that have been published recently. We found that the interplay between geometrical parameters such as grain size and aliquot size impacts the calibration value more than previously thought. The results of our study are robust and allow us to recommend an improved calibration procedure in order to enhance the reliability of the calibration value.
Dirk Mittelstraß and Sebastian Kreutzer
Geochronology, 3, 299–319, https://doi.org/10.5194/gchron-3-299-2021, https://doi.org/10.5194/gchron-3-299-2021, 2021
Short summary
Short summary
Our contribution enhances the infrared radiofluorescence dating technique, used to determine the last sunlight exposure of potassium feldspars in a range of about 600 to 600 000 years backwards. We recorded radiofluorescence images of fine sands and processed them with tailored open-source software to obtain ages from single grains. Finally, we tested our new method successfully on two natural sediment samples. Studies in Earth science will benefit from improved age accuracy and new insights.
Guillaume Guérin, Christelle Lahaye, Maryam Heydari, Martin Autzen, Jan-Pieter Buylaert, Pierre Guibert, Mayank Jain, Sebastian Kreutzer, Brice Lebrun, Andrew S. Murray, Kristina J. Thomsen, Petra Urbanova, and Anne Philippe
Geochronology, 3, 229–245, https://doi.org/10.5194/gchron-3-229-2021, https://doi.org/10.5194/gchron-3-229-2021, 2021
Short summary
Short summary
This paper demonstrates how to model optically stimulated luminescence (OSL) and radiocarbon ages in a Bayesian framework, using a dedicated software tool called BayLum. We show the effect of stratigraphic constraints, of modelling the covariance of ages when the same equipment is used for a series of OSL samples, and of including independent ages on a chronological inference. The improvement in chronological resolution is significant.
Daniela Mueller, Frank Preusser, Marius W. Buechi, Lukas Gegg, and Gaudenz Deplazes
Geochronology, 2, 305–323, https://doi.org/10.5194/gchron-2-305-2020, https://doi.org/10.5194/gchron-2-305-2020, 2020
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Luminescence properties of samples from the Rinikerfeld, northern Switzerland, are assessed. Reader-specific low preheat temperatures are invesigated to ensure suitable measurement conditions. While quartz is found to be dominated by stable fast components, signal loss is observed for feldspar and polymineral. In general, the ages of the fading corrected feldspar and the fine-grained polymineral fractions are in agreement with coarse-grained quartz, and ages indicate sedimentation during MIS6.
Galina Faershtein, Naomi Porat, and Ari Matmon
Geochronology, 2, 101–118, https://doi.org/10.5194/gchron-2-101-2020, https://doi.org/10.5194/gchron-2-101-2020, 2020
Short summary
Short summary
Optically stimulated luminescence dates the last exposure of quartz and feldspar minerals to sunlight. We investigated its sub-methods (TT-OSL, VSL, and pIRIR) to date middle and early Pleistocene sediments. Inspection of natural signals of samples can reveal saturated samples that produce only minimum ages. Using these sub-methods, minimum ages of up to the early Pleistocene can be obtained for eastern Mediterranean aeolian sediments of Nilotic origin.
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Short summary
We study the use of zircons as dosimeters using modern techniques, highlighting their advantages such as time-invariant dose rates. We explore the correlation between zircon geochemistry and luminescence properties, observe fast zircon optically stimulated luminescence (OSL) bleaching rates, and assess the potential of auto-regeneration. Low OSL sensitivities require combining natural OSL and auto-regenerated thermoluminescence (TL), with the potential to enhance age accuracy and precision.
We study the use of zircons as dosimeters using modern techniques, highlighting their advantages...
