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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 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.

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.

A novel technique for the uranium-lead dating of geologically young carbonates is described and tested. The technique expands our ability to date geological events such as fault movements and past climate records.

The timing and duration of fluid activity within a gold deposit enables a greater understanding of how the deposit evolved and thus help future mineral exploration. This research uses high resolution dating methods to unravel the overprinting fluid activity at the Martabe gold field in Sumatra. Methods outline in this report can be applied to deposits globally.

We carried out thermal annealing experiments between 500 and 1000 °C to determine the closure temperature of radiation-damage annealing in zircon (ZrSiO₄). Our results show that the different Raman bands of zircon respond differently to annealing. The repair is highest for the external rotation Raman band near 356.6 cm⁻¹. The closure temperature estimates range from 250 to 370 °C for different bands. The differences in closure temperatures offer the prospect of multi-T zircon Raman dating.

This paper shows that the current practice of filtering discordant U-Pb data based on the relative difference between the ²⁰⁶Pb / ²³⁸U and ²⁰⁷Pb / ²⁰⁶Pb ages is just one of several possible approaches to the problem, and demonstrably not the best one. An alternative approach is to define discordance in terms of isotopic composition, as a logratio distance between the measurement and the concordia line. Application to real data indicates that this reduces the positive bias of filtered age spectra.

This paper demonstrates how to model OSL and radiocarbon ages in a Bayesian framework, using a dedicated software tool called BayLum. We show the effect of stratigraphic constraints, of modelling the covariance of ages when the same equipment is used for a series of OSL samples, and of including independent ages on a chronological inference. The improvement in chronological resolution is significant.

Luminescence dating requires irradiating the sample in the laboratory. Some concerns have been published recently about the reliability of the calibration procedure. Here we have addressed these concerns. We found that the interplay between geometrical parameters such as grain size and aliquot size impact on the calibration more than previously thought. The results allow us recommending improved calibration procedure to enhance the reliability of the calibration value.

To explore the U-Pb geochronometer in fluorite, the spatial distribution of uranium and other substituted elements in natural crystals is investigated using induced fission-track and synchrotron radiation X-ray fluorescence mapping. LA-ICP-MS U-Pb dating on four crystals, that preserved micrometer-scale variations in U concentrations, yield identical ages within analytical uncertainty. Our results show that fluorite U-Pb geochronology has potential for dating distinct crystal growth stages.