The post-Caledonian tectonic history and landscape evolution of southwestern Norway are poorly understood, primarily owing to the lack of onshore post-Devonian sediments. To bridge this knowledge gap, low-temperature thermochronological techniques were applied to investigate vertical movements in the upper crust. New apatite fission track and apatite and zircon (U–Th)/He analyses on samples from southwestern Norway yielded Permian to Jurassic, Triassic to Cretaceous and Carboniferous to Triassic ages, respectively. Thermal history modelling indicates relatively high cooling rates (2–3 °C Ma−1) throughout Permian to early Jurassic times. Since the Jurassic, samples from coastal areas have remained close to the surface and were reheated to 30–50 °C during sedimentary burial in the Cretaceous. Inland samples experienced lesser amounts of Permo-Triassic exhumation, continued to cool slowly (<1 °C Ma−1) throughout the Jurassic–Cretaceous and did not reach the surface until the Cenozoic. Both fission track and (U–Th)/He ages are offset across faults, highlighting the importance of fault activity throughout the Mesozoic. In combination with previously published results, the new data suggest that the geomorphological evolution of southwestern Norway is closely connected to rift- and post-rift tectonics related to North Sea and North Atlantic rifting. The topographic relief was most likely repeatedly rejuvenated during periods of tectonic activity.

Determining the timing of post-Caledonian brittle faulting in northern Norway is important for the understanding of the extensional tectonic evolution of the north

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We assess the proposal of Hendriks & Redfield (Earth and Planetary Science Letters, 236, 443-458, 2005) that cross-over of the predicted apatite fission track (AFT) . (U-Th-Sm)/ He (AHe) age relationship in the southeastern Fennoscandian shield in southern Finland reflects a-radiation-enhanced annealing (REA) of fission tracks at low temperatures and that more robust estimates of the denudation history are recorded through reproducible AHe data. New AHe results from southern Finland showing variable dispersion of single-grain ages may be biased by different factors operating within grains, which tend to give a greater weighting towards older age outliers. AHe ages from mafic rocks show the least dispersion and tend to be consistently lower than their coexisting AFT ages. In general, it is at the younger end of the single-grain variation range from such lithologies where most meaningful AHe ages can be found. AHe data from multigrain aliquots are, therefore, of limited value for evaluating thermal histories in southern Finland, especially when compared against coexisting AFT data as supporting evidence for REA.New, large datasets from the southern Canadian and Western Australian shields show the relationship between AFT age, single-grain age or mean track length as a function of U content (determined by the external detector method). These do not display the moderately strong inverse correlations previously reported from southern Finland in support of REA. Rather, the trends are inconsistent and generally exhibit weak positive or negative correlations. This is also the case for plots from both shields, as well as those from southern Finland, where AFT parameters are plotted against effective U concentration [eU] [based on U and Th content determined by inductively coupled plasma-mass spectroscopy (ICP-MS)], which weights decay of the parents more accurately in terms of their a-productivity. Further, samples from southern Finland yield values of chi-square x 2 .5%, indicating that there is no significant effect of the range of uranium content between grains within samples on the AFT ages, and that they are all consistent with a single population.The oldest AFT ages in southern Finland apatites (amongst the oldest recorded from anywhere) are found in gabbros, which also have the highest Cl content of all samples studied. We suggest, that it is Cl content rather than REA that has influenced the annealing history of the apatites, which have experienced a history including reburial into the partial annealing zone by Caledonian Foreland basin sedimentation. The study of apatite from low U and Th rocks, with relatively low levels of a-radiation damage may provide the most practical approach for producing reliable results for AFT and AHe thermochronometry studies in cratonic environments.

To promote a more efficient and transparent geochemistry data ecosystem, a consortium of Australian university research laboratories called the AuScope Geochemistry Network assembled to build a collaborative platform for the express purpose of preserving, disseminating and collating geochronology and isotopic data. In partnership with geoscience‐data‐solutions company Lithodat Pty Ltd, the open, cloud‐based AusGeochem platform (https://ausgeochem.auscope.org.au) was developed to simultaneously serve as a geosample registry, a geochemical data repository and a data analysis tool. Informed by method‐specific groups of geochemistry experts and established international data reporting practices, community‐agreed database schemas were developed for rock and mineral geosample metadata and secondary ion mass spectrometry U‐Pb analysis, with additional models for laser ablation‐inductively coupled‐mass spectrometry U‐Pb and Lu‐Hf, Ar‐Ar, fission‐track and (U‐Th‐Sm)/He under development. Collectively, the AusGeochem platform provides the geochemistry community with a new, dynamic resource to help facilitate FAIR (Findable, Accessible, Interoperable, Reusable) data management, streamline data dissemination and advanced quantitative investigations of Earth system processes. By systematically archiving detailed geochemical (meta‐)data in structured schemas, intractably large datasets comprising thousands of analyses produced by numerous laboratories can be readily interrogated in novel and powerful ways. These include rapid derivation of inter‐data relationships, facilitating on‐the‐fly data compilation, analysis and visualisation.