Age–depth models assign ages to sampling locations (e.g., in drill cores), making them crucial to the determined timing and pace of past changes. We present two methods to estimate age–depth models from sedimentological and stratigraphic information, resulting in richer and more empirically realistic age–depth models. As a use case, we (1)  determine the timing of the Frasnian–Famennian extinction and (2) examine the duration of the Paleocene–Eocene Thermal Maximum (PETM), a potential deep-time analog for anthropogenic climate change.

We studied changes in Earth's magnetic field between 170 000 and 270 000 years ago using beryllium data from Antarctic ice. Our results reveal three periods when the magnetic field weakened, including one major event with a rapid fall and gradual recovery. These findings help explain how Earth's magnetic field behaves during short-term disturbances and improve the timing of past climate and geological records.

StratoBayes is a novel Bayesian method for aligning stratigraphic data from multiple sites. It integrates diverse information, such as geochemical signals and radiometric dates, and provides robust age estimates with quantified uncertainty for all sites. We use StratoBayes to correlate lower Cambrian δ¹³C records from Morocco with an undated record from Siberia, and estimate the age of the world’s oldest trilobites.

U–Pb dating of cave sediments has provided important new time constraints on the evolution of cave-dwelling organisms (including early humans) and of Earth's climate during the past 5 Myr. This paper shows that the most common type of U–Pb dating, which uses ²³⁸U and ²⁰⁶Pb, can be inaccurate beyond ca. 2 Myr ago. It proposes an alternative type of U–Pb dating, using ²³⁵U and ²⁰⁷Pb, as a more accurate alternative.

Paired moderate- and high-precision U–Pb geochronology is used to explore sources of young bias in laser-ablation-based detrital zircon maximum depositional ages (MDAs). We redefine the reference value for MDA accuracy as the age of the youngest analyzed population and reframe MDA algorithm assessments around validity. This study highlights opportunities to refine MDA research and anticipates continued community efforts to further improve accuracy of laser ablation zircon geochronology.

Marine sediments contain valuable information about past climate changes. However, dating Pleistocene marine sediments can be difficult, and the accuracy of the age model depends on the quality of the stratigraphic alignment target. We introduce three targets – Atlantic, Pacific, and global – with three distinct chronologies for the global target that incorporate astronomical forcing constraints to various degrees. This suite of targets offers flexibility in age model construction.

To improve U-Th zircon dating, we optimized a U-Th-Pb double-dating strategy for young zircon (150–300 ka). We found that the overall U-Th age spectrum is consistent whether assuming a constant melt composition or constant U/Th fractionation between zircon and melt, but testing the representability of the measured glass with the youngest isochron intercept proved essential. A Bayesian model with a uniform prior distribution gave the most accurate estimates of eruption timing for U-Th datasets.

To investigate the Laurentide Ice Sheet’s erosivity before and during the Last Glacial Maximum, we sampled sand deposited by ice in eastern Canada before final deglaciation. We also sampled modern river sand. The ²⁶Al and ¹⁰Be measured in glacial deposited sediments suggests that ice remained during some Pleistocene warm periods and was an inefficient eroder. Similar concentrations of ²⁶Al and ¹⁰Be in modern sand suggests that most modern river sediment is sourced from glacial deposits. 

The Llanos de Moxos (Bolivian Amazon) host thousands of anthropogenic forest islands from the Holocene. These sites contain shell middens primarily composed of freshwater snails (Pomacea spp.), often used for ¹⁴C dating. To evaluate potential radiocarbon reservoir effects (RRE), modern Pomacea shells and coeval tree leaves were analysed. Results reveal no significant RRE, supporting their reliability for dating archaeological and paleoecological records in the region.

We evaluate different methods for the potassium (K) concentration determination in feldspars and the impact of the K concentrations on dose rate calculations for feldspar luminescence dating. Our results show discrepancies between published K concentrations and our measured K concentrations. Therefore, we emphasize measuring K concentrations via bulk measurements and single-grain techniques to obtain more accurate results.

This study examines the feasibility of dating beach ridges associated with pluvial lake highstands in the Great Basin, USA, using rock surface luminescence dating techniques. Limestone and volcanic rock lithologies prominent in this region pose challenges, but preliminary measurements show promise. We show that ages derived from beach ridge gravel rocks record the timing of lake highstands as well as climatically driven soil formation processes.

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.

We present an open-access Python package (GDTchron) designed to forward model apatite (U-Th)/He, apatite fission track, and zircon (U-Th)/He ages using temperatures output by geodynamic numerical models. The software can be used in a parallelized workflow to calculate large numbers of ages. We present two examples of potential applications of GDTchron: a simple model of exhumation and a complex model of continental rifting followed by mountain building.

Chemical abrasion (CA) is a two-step method for reducing Pb loss where zircon is annealed then partially dissolved. We use secondary ion mass spectrometry (SIMS) to find closed- and open-system zircon domains in zircon that has been chemically abraded, annealed only, or untreated. Raman mapping identifies lattice damage in SIMS spots. Atom probe tomography (APT) results from both the discordant spots and the concordant ones are all homogeneous and identical. Thus, APT cannot distinguish discordant and concordant zircon.

We show that portable X-ray fluorescence can be used to rapidly (ca. 90 s) estimate the rate of background radioactivity in sediment used to calculate burial ages in trapped charge dating studies. This procedure involves inputting a measurement of potassium concentration into a set of simple regression equations, defined by a large radionuclide dataset. Results show good agreement with high-precision methods. Our rapid method will help to quickly generate burial age estimates.

In this study, Optically Stimulated Luminescence (OSL), Electron Spin Resonance (ESR) and Laser Ablation-Induced Coupled Plasma-Mass Spectroscopy (La-ICPMS) trace element (TE) analyses shows that TE composition may influence OSL and ESR-Ti sensitivities in quartz, which vary with bedrock type. Pressure may take a part in OSL/ESR-Ti sensitivities variability while ESR-Al intensities could be linked to initial fluid composition and crystallization conditions

The Christiana Islands represents the oldest subaerial volcanism in the Christiana-Santorini-Kolombo volcanic field, but the exact age of this volcano has been unknown. This study reports new ⁴⁰Ar/³⁹Ar ages of ten volcanic samples from Christiana Island that cluster between 2.5–2.7 Ma with small uncertainties (0.02–0.14 Ma). One sample dated much younger: 133 ka; this is most likely derived from the Middle Pumice Plinian eruption of Santorini.

Helium gas accumulates over time in minerals, but loss can occur depending on temperature. If partially retained, its loss can potentially be used for determining past surface temperatures. This study uses a model that accounts for complex gas loss to analyze helium retention in two minerals commonly found on the surface of Antarctica. We find one of the minerals retains helium, while the other loses nearly all of the gas within 100 years, making it unsuitable as a climate reconstruction.

Bayesian modelling is often used to refine numerically dated chronological sequences, e.g., by making use of stratigraphic constraints. First, a high-resolution dataset based on luminescence dating is modelled with the dedicated R package BayLum. Then, three Bayesian modelling tools – namely BayLum, Chronomodel and OxCal – are compared using a high-resolution, radiocarbon dataset. Modelling artefacts are identified; the strengths and weaknesses of the models are discussed.

This study investigates Rb–Sr system behavior in hydrothermally altered muscovite using in-situ LA-ICP-MS/MS (Laser Ablation-Inductively Coupled Plasma-Tandem Mass Spectrometry) analyses from the Athabasca Basin. Unaltered muscovite records Paleoproterozoic crystallization ages, whereas muscovite altered to illite and sudoite yields a consistent age of ~1640 Ma, corresponding to alteration halos related to unconformity-type uranium deposits. These results highlight the potential of Rb–Sr dating to constrain hydrothermal processes and fluid–rock interactions.

We developed a faster and simpler method to measure helium gas in targeted minerals within whole rocks to determine how long they have been exposed at Earth's surface. Instead of manually separating minerals, our method uses heat to release gas from the specific minerals of interest. This reduces time, cost, and physical effort, making it easier to collect large amounts of data when studying landscape change or when only small rock samples are available.

(U-Th-Sm)/He dating is a tool to investigate when and how rocks cooled through the upper Earth’s crust. We explore strategies to reconstruct thermal histories of individual apatite crystals by direct measurement of their helium concentration profile and radionuclide distribution. This approach allows for the inclusion of inhomogeneous grains in thermal modelling, which is often problematic in traditional (U-Th-Sm)/He methods.

We evaluate luminescence signal resetting in single-grain K-feldspar from modern fluvial analogues in Chile. Our results show a uniform sample-average bleaching trend but strong grain-scale variability. Residual doses are independent of feldspar geochemistry and catchment lithology but scale with natural dose. Taken together, these findings refine palaeodose correction strategies and support defining sample‑specific bleaching thresholds for luminescence‑based sediment tracing.

The ability to reconstruct thermal histories from thermochronometric data is determined by kinetic parameters. The Great Unconformity represents an enormous amount of time lost from the sedimentary record and has been explored with zircon (U–Th)/He ages. 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.

The mineral biotite is a common rock-forming mineral and notable for its ability to incorporate Rb into its structure. Microanalytical tools such a laser ablation and tandem mass spectrometry, allows Rb-Sr biotite dating with context preserved. This study reveals Sr mobility that is controlled by location in a rock. Reconstructing the timing of geological events using biotite Rb-Sr geochronology is, therefore, contingent on grain-scale evaluation of biotite textures.

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.

This study dated chrysocolla, a supergene copper mineral, from copper deposits hosted in the Coastal Cordillera of northern Chile, with ages between 8.0 and 0.045 million years. Results show that from the Late Miocene to the Pleistocene, short periods of moisture triggered mineral formation despite the hyperarid climate. These wetter periods were likely caused by occasional rainfall or stronger coastal fog, causing repeated pulses of supergene activity in the Coastal Cordillera.

geochron@home is a free and open-source platform that makes fission track dating more transparent and reliable. It combines a virtual microscope with an online database to share images and data openly, following FAIR principles. Researchers can analyse tracks privately, archive data for peer review, teach students, or involve citizen scientists. By improving data access and reproducibility, geochron@home helps build trust and supports future advances in Earth science.

(U-Th)/He chronology requires measuring the absolute amount of radiogenic He in a sample. While high-quality commercial He lines are available, these machines are not always ideal for researchers interested in developing new or emerging techniques like laser ablation (U-Th)/He chronology. This manuscript describes the design, construction, automation, and calibration of a new He analysis line in the University of Colorado Thermochronology Research and Instrumentation Lab (CU TRaIL) facility that is optimized for measuring small amounts of He.

Ice sheet mass loss is adding to sea-level rise, and is expected to increase, but by how much and how fast remains uncertain. Isotopes produced in rock at the Earth’s surface provide records of past ice sheet thinning which help predict future change but are more effective if they are precise enough to determine past changes to the nearest thousand years. Carbon-14 is a unique isotope that provides an accurate record of past change since the last ice age, however, its precision can be improved.

Conventional (U-Th)/He thermochronology requires accurate calculation of mineral grain volume, often based on approximations to idealized geometries. However, there are many instances where knowingly altering the geometry by polishing grains for additional in situ data collection is desirable. This contribution provides a new method to calculate volume and other data for polished grains used in zircon (U-Th)/He thermochronology analysis using no-added-cost modifications of existing workflows.

Natural fission of Uranium U-238 in minerals produce tracks in the crystal lattice. The density of tracks crossing the mineral surface is traditionally used together with the uranium concentration and the decay constant to calculate the age of fast-cooling minerals. A new equation is developed which includes the track length distribution of the tracks. It is then possible to age date the tracks as a function of their length. A detailed tectonic history of the minerals can then be derived.

Cosmogenic surface-exposure dating relies on accurate constraint of nuclide production rates. To improve dating resolution, we compare ¹⁰Be concentrations in deglacial surfaces in Scotland to local ¹⁴C targets to test the performance of 8 production rates. Of these, the Rannoch Moor rate from central Scotland gives the best fit with the ¹⁴C; others under-predict exposure age by up to 7 %. Our ¹⁰Be record also shows retreat of the last ice sheet was disrupted by a brief pause ~16 200 years ago.

To accurately understand past climate change, exact chronologies are fundamental. We dated multiple stalagmites from the Yucatán Peninsula covering the last 2700 years. Because these cave deposits contain high and variable amounts of contaminating elements that distort age models, we developed a multi-method approach to correct the timelines. Our corrected records now provide a reliable foundation for future studies to track ancient droughts, floods, and their links to Maya cultural evolution.

We present a new strategy for extracting information on the thermal history of sedimentary samples that lost part of their radiogenic helium during sediment burial. It uses combined U/Pb and (U-Th)/He dating of zircon to find grains that formed just before deposition and use them to model the basin thermal history. The model also estimates the time when the source rock of each grain cooled. We discuss the advantages and limitations of our approach and its application to other methods.

We present a high-sensitivity laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) method for in-situ U–Pb dating of garnet with under 1 ng g⁻¹ U. Using ion counters, geologically meaningful ages are obtained from garnets with up to three orders of magnitude less uranium than standard in-situ U–Pb dating. This expands garnet petrochronology to low-U metamorphic rocks.