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Developing models that relate stratigraphic position to time are important because they allow the rock record to be understood in terms of absolute time, allowing global comparisons. We developed a novel method for developing these models (called age–depth models) that uses two different types of chronologic information, dated rocks, and records of variations in the Earth's orbit (astrochronology). The resulting models are very precise, which can improve understanding of past climates.

Chemical abrasion (CA) is a technique that reduces or eliminates the effects of Pb loss in zircon U–Pb geochronology. However, CA has yet to be applied to large-n detrital zircon (DZ) analyses. We show that CA does not negatively impact or systematically bias U–Pb dates, improves the resolution of age populations defined by ²⁰⁶Pb/²³⁸U dates, and increases the percentage of concordant analyses in age populations defined by ²⁰⁷Pb/²⁰⁶Pb dates.

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.

Reliable chronologies lie at the base of paleoclimatological reconstructions. When working with marine sediment cores, the most common dating tool for recent sediments is radiocarbon, but this requires calibration to convert it to calendar ages. This calibration requires knowledge of the marine radiocarbon reservoir age, and this is known to vary in space and time. In this study we provide 92 new radiocarbon measurements to improve our knowledge of the reservoir age around Greenland.

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.

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 describe a new method of reconstructing the long-term, pre-observational frequency and/or intensity of wildfires in forested landscapes using trace concentrations of the noble gases helium and neon that are formed in soil mineral grains by cosmic-ray bombardment of the Earth's surface.

Radiometric dating methods, involving laser ablation as the sample introduction, require robust calibrations to reference materials with similar ablation properties to the analysed samples. In the case of the rubidium–strontium dating method, calibrations are often conducted to nano powder with different ablation characteristics than the crystalline minerals. We describe the limitations of this approach and recommend an alternative calibration method involving natural minerals.

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.

We present oxygen isotope data for a new sediment core from the South Pacific and assign ages to our record by aligning distinct patterns in observed oxygen isotope changes to independently dated target records with the same patterns. We examine the age uncertainties associated with this approach caused by human vs. automated alignment and the sensitivity of outcomes to the choice of alignment target. These efforts help us understand the timing of past climate changes.

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.

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.

The mineral zircon is widely used to determine the age of rocks based on the radioactive decay of U to Pb, but the measured U–Pb date can be too young if the zircon loses Pb. We present a method for estimating the distribution of apparent Pb loss by mathematical convolution. Applying this approach to 10 samples illustrates contrasting patterns of apparent Pb loss. This study highlights the importance of quantifying Pb loss to better understand its potential effects on zircon U–Pb dates.

Acid leaching is used to remove radiation-damaged portions of zircon crystals prior to U–Pb dating to improve the accuracy of datasets. We test how the temperature and duration of acid leaching affect geochronological and geochemical outcomes. We build a framework that relates radiation damage, zircon solubility, and Pb loss.

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.