Chemical abrasion (CA) is a two step method for reducing Pb loss where zircon is annealed then partially dissolved. We use SIMS to find closed and open system zircon domains in zircon that has been CA, annealed only, or untreated. Raman mapping shows to identify lattice damage in SIMS spots. Atom Probe (APT) results from both the discordant spots and concordant ones are all homogenous and identical. Thus APT cannot distinguish discordant and concordant zircon.

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.

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.

We report 31 new ¹⁰Be and 26 recalculated ³⁶Cl dates from the Sierra Nevada Mountains (USA) and conclude that deglaciation’s final and rapid phase began at 16.4 ± 0.8 ka. In comparing this timing with high-resolution regional paleoclimate proxies, we interpret that rapid deglaciation most likely began at 16.20 ± 0.13 ka, which is indistinguishable in timing from Heinrich Event 1. We interpret that the range’s deglaciation was likely driven by a reunification of the polar jet stream at this time.

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 hundred years, making it unsuitable as a climate reconstruction.

We present the first community evaluation of the reproducibility of U–Pb zircon geochronology by ID-TIMS. Eleven labs in the experiment analysed aliquots of the same, homogenised, pre-spiked solution of natural zircon. This removed geological bias inherent to using natural zircon grain populations and allowed focussing the study on final lab preparation and mass spectrometry. We discuss remaining sources of inter-lab bias and propose areas of improvement of analytical methods.

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 technical note develops and demonstrates an improvement in how to calculate the temperatures experienced by rocks as they come to the Earth surface due to erosion in mountainous regions. 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 geochronologic data to help discern the history of mountain ranges.

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 and our measured K-concentrations. Therefore, we emphasise to measure K-concentrations via bulk measurements and single-grain techniques to obtain more accurate results.

Paired low- and high-precision U–Pb geochronology data are evaluated to better understand young bias in laser ablation dates and detrital zircon maximum depositional ages (MDAs). We redefine the reference for MDA accuracy as the true 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.