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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.

Phanerozoic sedimentary rocks of northern Canada have compositionally heterogeneous detrital apatite with high age dispersion caused by differential thermal annealing. Discrete apatite fission track kinetic populations with variable annealing temperatures are defined using elemental data but are poorly resolved using conventional parameters. Inverse thermal modelling of samples from northern Yukon reveals a record of multiple heating–cooling cycles consistent with geological constraints.

The standard approach to isochron calculation assumes that the distribution of uncertainties on the data arising from isotopic analysis is strictly Gaussian. This excludes datasets that have more scatter, even though many appear to have age significance. Our new approach requires only that the central part of the uncertainty distribution of the data defines a "spine" in the trend of the data. A robust statistics approach is used to locate the spine, and an implementation in Python is given.

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.

Dating low-grade metamorphic rocks with the ⁴⁰Ar / ³⁹Ar method is difficult because samples are fine-grained mixtures between detrital and newly grown metamorphic minerals. We use a careful step-heating schedule and resolve limits within the complex age spectra thus derived to infer the timing of metamorphism and deformation in the Delamerian Orogen (formerly part of eastern Gondwana). Results suggest detrital mineral from up to 1172 Ma and that metamorphic minerals grew at 470–458 Ma.

We use age–depth modeling systems to understand the relationship between age and depth in lake sediment cores. However, depending on which modeling system we use, the model results may vary. We provide a tool to link different modeling systems in an interactive computational environment and make their results comparable. We demonstrate the power of our tool by highlighting three case studies in which we test our application for single-sediment cores and a collection of multiple sediment cores.

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.

This paper describes geoChronR, an R package that streamlines the process of quantifying age uncertainties, propagating uncertainties through several common analyses, and visualizing the results. In addition to describing the structure and underlying theory of the package, we present five real-world use cases that illustrate common workflows in geoChronR. geoChronR is built on the Linked PaleoData framework, is open and extensible, and we welcome feedback and contributions from the community.

Orakei Basin – a former maar lake in Auckland, New Zealand – provides an outstanding sediment record over the last ca. 130 000 years, but an age model is required to allow the reconstruction of climate change and volcanic eruptions contained in the sequence. To construct a relationship between depth in the sediment core and age of deposition, we combined tephrochronology, radiocarbon dating, luminescence dating, and the relative intensity of the paleomagnetic field in a Bayesian age–depth model.

We investigate the timing and rate of retreat for three alpine glaciers in the southern Rocky Mountains to test whether they followed the pattern of global climate change or were majorly influenced by regional forcing mechanisms. We find that the latter is most likely for these glaciers. Our conclusions are based on a new ¹⁰Be chronology of alpine glacier retreat. We quantify retreat rates for each valley using the BACON program in R, which may be of interest for the audience of Geochronology.

We compare two published U–Pb and ⁴⁰Ar / ³⁹Ar geochronologic datasets to produce eruption rate models for the Deccan Traps large igneous province. Applying the same approach to each dataset, the resulting models agree well, but the higher-precision U–Pb dataset results in a more detailed eruption model than the lower-precision ⁴⁰Ar / ³⁹Ar data. We explore sources of geologic uncertainty and reiterate the importance of systematic uncertainties in comparing U–Pb and ⁴⁰Ar / ³⁹Ar datasets.

Nikon–TRACKFlow is a new system with dedicated modules for automated microscope control and imaging for fission track laboratories. It is based on the Nikon Eclipse Ni-E motorised upright microscope and embedded within Nikon NIS-Elements software. The system decouples image acquisition from analysis based on a number of automated user-friendly designs and protocols. Nikon–TRACKFlow aims to grow towards a high-throughput imaging system for Earth Sciences and other material-oriented sciences.

When first introduced together with the depth profile technique to determine the surface exposure age, the linear inversion approach has suffered with the drawbacks of not incorporating erosion and muons into calculation. In this paper, we increase the accuracy and applicability of the linear inversion approach by fully considering surface erosion, muogenic production, and radioactive decay, while maintaining its advantage of being straightforward to determine an exposure age.

Annually banded lake sediment can track environmental change with high resolution in locations where alternatives are not available. Yet, information about chronology is often affected by poor appearance. Traditional methods struggle with these records. To overcome this obstacle we demonstrate a Bayesian approach that combines information from radiocarbon dating and laminations on cores from Columbine Lake, Colorado, expanding possibilities for producing high-resolution records globally.

Levinson-Lessing Lake in northern central Siberia provides an exceptional opportunity to study the evolution of the Earth's magnetic field in the Arctic. This is the first study carried out at the lake that focus on the palaeomagnetic record. It presents the relative palaeointensity and palaeosecular variation of the upper 38 m of sediment core Co1401, spanning ~62 kyr. A comparable high-resolution record of this time does not exist in the Eurasian Arctic.

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.

Fission tracks are generated in minerals due to spontaneous fission of uranium-238. The initial track length decreases with time due to recrystallization. The age of a track can be calculated by counting the number of the shorter tracks per volume and including the decay constant. However, the theoretical order of the track length versus time is disrupted by uncertainties. We shown how the order can be re-established. The age of tectonic events such as uplift and burial can then be determined.

We generated a synthetic dataset applying published kinetic models and distinct annealing kinetics for the apatite fission track and (U–Th)/He methods using a predetermined thermal history. We then tested how well the true thermal history could be recovered under different data interpretation schemes and geologic constraint assumptions using the Bayesian QTQt software. Our results demonstrate that multikinetic data increase time–temperature resolution and can constrain complex thermal histories.

Meteoric beryllium-10 concentrations in soil profiles have great capacity to quantify Earth surface processes, such as erosion rates and landform ages. However, determining these requires an accurate estimate of the delivery rate of this isotope to local sites. Here, we present a new method to constrain the long-term delivery rate to an eroding western US site, compare it against existing delivery rate estimates (revealing considerable disagreement between methods), and suggest best practices.

Cosmogenic nuclides are now widely applied in the Earth sciences; however, more recent applications often push the analytical limits of the technique. Our study presents a comprehensive method for analysis of cosmogenic ¹⁰Be and ²⁶Al samples down to isotope concentrations of a few thousand atoms per gram of sample, which opens the door to new and more varied applications of cosmogenic nuclide analysis.

Calcite is frequently formed during alteration processes in the basaltic, uppermost layer of juvenile oceanic crust. Weathered oceanic basalts are hard to date with conventional radiometric methods. We show in a case study from the North Pamir, Central Asia, that calcite U–Pb age data, supported by geochemistry and petrological microscopy, have potential to date sufficiently old oceanic basalts, if the time span between basalt extrusion and latest calcite precipitation (~ 25 Myr) is considered.

Subarctic and Arctic lake sediments provide key data to understand natural climate variability and future climate change. However, they can be difficult to date accurately and of limited use without a robust chronology. We use volcanic ash deposits from the last ~4000 BP to identify anomalously old radiocarbon ages at Cascade Lake, Alaska. A provisional ~15 000-year Bayesian age model is produced for the lake, and a new location for ash from five Late Holocene eruptions is reported.

This research is part of a PhD thesis examining evaporite detachments characteristics. ⁴⁰Ar/³⁹Ar geochronology is employed to constrain the timing of formation and deformation events. A diagenetic age of ~514 Ma is interpreted from the oldest significant step age. Other step ages may represent a Cambrian–Permian deformation event or a complex mixing age of diagenetic Ar with partially reset Ar during the Cenozoic. We report the first closure temperature for polyhalite between 254 and 277 °C.

We describe the design and performance of a new noble gas mass laboratory dedicated to the development of and application to cosmogenic nuclides at the University of Cologne (Germany). At the core of the laboratory are a state-of-the-art high-mass-resolution multicollector Helix MCPlus (Thermo-Fisher) noble gas mass spectrometer and a novel custom-designed automated extraction line, including a laser-powered extraction furnace. Performance was tested with intercomparison (CREU-1) material.

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.

Here we present the foundation dataset for TephraNZ, a formal, comprehensive, open-access reference dataset of glass-shard compositions for New Zealand tephras. We geochemically characterise 45 eruptive episodes ranging from Kaharoa (ca. 636 cal yr BP) to the Hikuroa Pumice member (ca. 2.0 Ma) from six or more caldera sources, most from the central Taupō Volcanic Zone.

Artificial intelligence techniques are capable of automatically detecting fission tracks in minerals. The AI-Track-tive software presented here can be used to automatically determine fission track densities for apatite fission track dating studies. Apatite fission track dating is mainly applied to tectonic research on exhumation rates in orogens. Time-consuming manual track counting can be replaced by deep neural networks capable of automatically finding the large majority of tracks.

High-resolution geochronology is one of the key factors to predict volcanic eruptions. To build up a high-resolution geochronological framework, we reported 21 new high-precision eruption ages (⁴⁰Ar / ³⁹Ar) for a ~ 3.3 × 10⁶-year-old volcanic field: Milos (Greece). In combination with geochemical information and eruption volumes from the volcanoes of Milos, the long-lived volcanic history could provide important clues for the prediction of volcanic eruptions.

In this study, we built a statistical model to determine the initial δ²³⁴U in submerged calcite crusts that coat the walls of Devils Hole 2 (DH2) cave (Nevada, USA) and, using a ²³⁴U–²³⁸U dating method, extended the chronology of the calcite deposition beyond previous well-established ²³⁰Th ages and determined the oldest calcite deposited in this cave, a time marker for cave genesis. The novel method presented here may be used in future speleothem studies in similar hydrogeological settings.

Distinguishing between different dolomitization processes is challenging yet critical for resolving some of the issues and ambiguities related to the formation of dolomitic rocks. Accurate U–Pb absolute dating of dolomite by LA-ICP-MS could contribute to a better understanding of the dolomitization process by placing syngenetic, early diagenetic, and/or epigenetic events in the proper geological context.

Geologic dating methods generally do not directly measure ages. Instead, interpreting a geochemical measurement as an age requires a middle layer of calculations and supporting data, and the fact that this layer continually improves is an obstacle to synoptic analysis of geochronological data. This paper describes a prototype data management and analysis system that addresses this obstacle by making the middle-layer calculations transparent and dynamic to the user.

We show results from a new type of ion detector technology for mass spectrometry that allows us to measure ion beams more precisely. This technology expands the range of ages we can measure using a single instrument and makes it possible to measure those ages – including all required corrections and adjustments – with more confidence. We show measurements of widely used standard materials for Ar / Ar, including air and synthetic standard gas, to illustrate the capabilities of the new detectors.

The dating of carbonates by laser ablation inductively coupled plasma mass spectrometry is improved by an additional, newly characterised reference material and adapted data evaluation protocols: the shape (diameter to depth) of the ablation crater has to be as similar as possible in the reference material used and the unknown samples to avoid an offset. Different carbonates have different ablation rates per laser pulse. With robust uncertainty propagation, precision can be as good as 2–3 %.

Our study presents the first seasonally laminated (varved) sediment record covering almost the entire Holocene in high mountainous arid Central Asia. The established floating varve chronology is confirmed by two terrestrial radiocarbon dates, whereby aquatic radiocarbon dates reveal decreasing reservoir ages up core. Changes in seasonal deposition characteristics are attributed to changes in runoff and precipitation and/or to evaporative summer conditions.

The generation of highly precise and accurate ages requires crushing of the original sample so that individual mineral grains may be separated out for dating. Here, we use a focused ion beam to extract grains directly from a subset of a sample, effectively performing microsurgery to isolate individual crystals from the rock itself. This approach opens the door to high-precision dating for a variety of precious planetary materials that have previously been challenging to date.

We report amino acid racemization analyses of foraminifera from well-dated sediment cores from the Yermak Plateau, Arctic Ocean. Sample ages are compared with model predictions, revealing that the rates of racemization generally conform to a global compilation of racemization rates at deep-sea sites. These results highlight the need for further studies to test and explain the origin of the purportedly high rate of racemization indicated by previous analyses of central Arctic sediments.

(U–Th) / He chronometry relies on accurate grain-specific size and shape measurements. Using > 100 apatite grains to compare assumed 2-D versus true 3-D grain shapes measured by a microscope and X-ray computed tomography, respectively, we find that volume and surface area both differ by ~ 25 % between the two techniques and directly affect mass and concentration measurements. But we found a very small effect on the FT correction (2 %) and no discernible impact on mean sample age or dispersion.