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New exposure ages of glacial erratics on moraines on Isle Royale – the largest island in North America's Lake Superior – show that the Laurentide Ice Sheet did not retreat from the island nor the south shores of Lake Superior until the early Holocene, which is later than previously thought. These new ages unify regional ice retreat histories from the mainland, the Lake Superior lake-bottom stratigraphy, underwater moraines, and meltwater drainage pathways through the Laurentian Great Lakes.

Acid leaching is commonly used to remove damaged portions of zircon crystals prior to U–Pb dating. However, a basic understanding of the microstructural processes that occur during leaching is lacking. We present the first 3D view of zircon dissolution based on X-ray computed tomography data acquired before and after acid leaching. These data are paired with images of etched grain surfaces and Raman spectral data. We also reveal exciting opportunities for imaging radiation damage zoning in 3D.

The island of Patmos is situated in the southern Aegean Sea (Greece), just north of the present locus of active volcanism. The island is almost entirely built up of volcanic rocks that are 6.6 to 5.2 million years old. We obtain these ages with ⁴⁰Ar / ³⁹Ar dating technique on sanidine and biotite minerals. Our new age data indicate a geologically brief volcanic period (lasting less than 1.5 million years) that can be divided into three volcanic intervals and correlated to tectonics.

Sediment cores from the volcanic lake Holzmaar provide a very precise chronology based on tree-ring-like annual laminations or varves. We statistically combine this varve chronology with radiometric dating and tested three different methods to upgrade the age–depth model. However, only one of the three methods tested improved the dating accuracy considerably. With this work, an overview of different age integration methods is discussed and made available for increased future demands.

The marine reservoir age (MRA) is the difference between the ¹⁴C age of the ocean and that of the atmosphere at a given time. In geochronology, knowing the local MRA is important to derive accurate calibrated ages for ¹⁴C-dated marine material. However, MRA values for coastal West Africa are scarce. From the ¹⁴C dating of known-age bivalves from museum collections, we calculated MRA values and populated the MRA dataset for coastal West Africa over a latitudinal transect from 33°N to 15°S.

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.

We propose using the Wasserstein-2 distance (W₂) as an alternative to the widely used Kolmogorov–Smirnov (KS) statistic for analysing distributional data in geochronology. W₂ measures the horizontal distance between observations, while KS measures vertical differences in cumulative distributions. Using case studies, we find that W₂ is preferable in scenarios where the absolute age differences in observations provide important geological information. W₂ has been added to the R package IsoplotR.

We report aspartic and glutamic acid racemization analyses on Neogloboquadrina pachyderma and Cibicidoides wuellerstorfi from the Arctic Ocean (AO). The rates of racemization in the species are compared. Calibrating the rate of racemization in C. wuellerstorfi for the past 400 ka allows the estimation of sample ages from the central AO. Estimated ages are older than existing age assignments (as previously observed for N. pachyderma), confirming that differences are not due to taxonomic effects.

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.

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.

Chronological information on the evolution of the Namib Desert is scarce. We used U–Pb dating of silcretes formed by pressure solution during calcrete formation to track paleoclimate variability since the Late Miocene. Calcrete formation took place during the Pliocene with an abrupt cessation at 2.9 Ma. The end took place due to deep canyon incision which we dated using TCN exposure dating. With our data we correct and contribute to the Neogene history of the Namib Desert and its evolution.

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.

We describe a new, fully automated extraction system for in situ ¹⁴C at PRIME Lab that incorporates more reliable components and designs than our original systems. We use a LiBO₂ flux to dissolve a quartz sample in oxygen after removing contaminant ¹⁴C with a lower-temperature combustion step. Experiments with new Pt/Rh sample boats demonstrated reduced procedural blanks, and analyses of well-characterized intercomparison materials tested the effects of process variables on ¹⁴C yields.

Radiocarbon dating is a widely used tool to establish chronologies for sediment records. We show that modern aquatic plants in the Laguna del Peinado lake system (Altiplano–Puna Plateau) give overestimated ages due to reservoir effects from the input of old groundwater and volcanic CO₂. Our results reveal a spatial variability in the modern reservoir effect within the lake basin, which has implications for radiocarbon-based chronologies in paleoclimate studies in this (and similar) regions.

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.

Cosmogenic nuclides like ¹⁰Be are rare isotopes created in rocks exposed at the Earth’s surface and can be used to understand glacier histories and landscape evolution. ¹⁰Be is usually measured in the mineral quartz. Here, we show that ¹⁰Be can be reliably measured in the mineral pyroxene. We use the measurements to determine exposure ages and understand landscape processes in rocks from Antarctica that do not have quartz, expanding the use of this method to new rock types.

We present our model ChronoLorica. We coupled the original Lorica model, which simulates soil and landscape evolution, with a geochronological module that traces cosmogenic nuclide inventories and particle ages through simulations. These properties are often measured in the field to determine rates of landscape change. The coupling enables calibration of the model and the study of how soil, landscapes and geochronometers change under complex boundary conditions such as intensive land management.

Accurately dating ocean cores is challenging because the radiocarbon age of water masses varies substantially. We identify ash fragments from eruptions more than 4000 km from their source and use these time markers to develop a new age–depth model for an ocean core in Placentia Bay, North Atlantic. Our results show that the radiocarbon age of waters masses in the bay varied considerably during the last 10 000 years and highlight the potential of using ultra-distal ash deposits in this region.

(U–Th) / He dating relies on proper characterization of apatite crystal dimensions so that eU concentrations and dates can be calculated accurately and precisely, but there is systematic error and uncertainty in geometric measurements. By comparing 2D microscopy to true 3D measurements, we present a simple solution to correcting the error and quantifying the geometric uncertainty in eU and dates. Including this geometric correction and uncertainty matters for data evaluation and interpretation.

When using the uranium–lead (U–Pb) radiometric dating method on very young materials (e.g. Quaternary age zircon and carbonate minerals), it is important to accurately account for the production and decay of intermediate daughter isotopes in the uranium-series decay chain. DQPB is open-source software that allows users to easily perform such calculations for a variety of sample types and produce publication-ready graphical outputs of the resulting age information.

About 2 million years ago, rich gold deposits formed at Martabe, on the island of Sumatra in Indonesia. Fluids may have moved as the result of fault dilation caused by changes in stress orientation during the earthquake cycle, so to work out exactly when and how long between cycles, we dated a potassium-bearing mineral, alunite, using argon geochronology in association with diffusion experiments during temperature-controlled furnace step-heating, showing two episodes 250 thousand years apart.

We developed code to automatically and semi-automatically measure dimensions of detrital mineral grains in reflected-light images saved at laser ablation–inductively coupled plasma–mass spectrometry facilities that use Chromium targeting software. Our code uses trained deep learning models to segment grain images with greater accuracy than is achievable using other segmentation techniques. We implement our code in Jupyter notebooks which can also be run online via Google Colab.

There is currently no standardized method of performing uncertainty propagation in the (U–Th) / He system, causing data interpretation difficulties. We present two methods of uncertainty propagation and describe free, open-source software (HeCalc) to apply them. Compilation of real data using only analytical uncertainty as well as 2 % and 5 % uncertainties in FT yields respective median relative date uncertainties of 2.9 %, 3.3 %, and 5.0 % for apatites and 1.7 %, 3.3 %, and 5.0 % for zircons.

Thermochronometric data can provide unique insights into the patterns of rock exhumation and the driving mechanisms of landscape evolution. Several well-established thermal models allow for a detailed exploration of how cooling rates evolved in a limited area or along a transect, but more regional analyses have been challenging. We present age2exhume, a thermal model that can be used to rapidly provide a synoptic overview of exhumation rates from large regional thermochronologic datasets.

In situ ¹⁴C’s short half-life (5.7 kyr) is unique among cosmogenic nuclides, making it sensitive to complex exposure and burial histories since 25 ka. Current extraction methods focus on quartz, but the ability to extract it from other minerals would expand applications. We developed MATLAB® scripts to calculate in situ ¹⁴C production rates from a broad range of mineral compositions. Results confirm O, Si, Al, and Mg as key targets but also find significant production from Na for the first time.

SHRIMP (Sensitive High Resolution Ion MicroProbe) is an instrument that for decades has used the radioactive decay of uranium into lead to measure geologic time. The accuracy and precision of this instrument has not been seriously reviewed in almost 20 years. This paper compares several dozen SHRIMP ages in our database with more accurate and precise methods to assess SHRIMP accuracy and precision. Analytical and geological complications are addressed to try to improve the method.

Deposits left behind by past glacial activity provide insight into the previous size and behavior of glaciers and act as another line of evidence for past climate. Here we present new age control for glacial deposits in the mountains of Montana and Wyoming, United States. While some deposits indicate glacial activity within the last 2000 years, others are shown to be older than previously thought, thus redefining the extent of regional Holocene glaciation.

We constrained deposition phases of fluvial sediments (NE Belgium) over the last 1 Myr with analysis and modelling of rare isotopes accumulation within sediments, occurring as a function of time and inverse function of depth. They allowed the determination of three superposed deposition phases and intercalated non-deposition periods of ~ 40 kyr each. These phases correspond to 20 % of the sediment age, which highlights the importance of considering deposition phase when dating fluvial sediments.

If topographical obstructions are present in the surroundings of sampling sites, exposure ages of rock surfaces need to be corrected. A toolbox for the ESRI ArcGIS software allows for quantifying topographic shielding with a digital elevation model, but it has only been validated with few field data. In this study, the output of the toolbox is evaluated with a more extensive dataset. If suitable elevation data are chosen, the toolbox provides a sound approach to determine topographic shielding.