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ItemThermochronological insights into the morphotectonic evolution of Zimbabwe, southern Africa( 2017)The Zimbabwe Craton and surrounding mobile belts that make up Zimbabwe form the north-eastern part of the Southern African Plateau, which is of great scientific interest due to its anomalous elevation. The Phanerozoic history of Zimbabwe is largely unresolved and is difficult to unravel using conventional field methods due to the fragmentary nature of the preserved geological record and lack of structural controls in the dominantly granitic lithologies. Low-temperature thermochronology systems provide an invaluable toolkit for understanding upper crustal processes and in turn deciphering cryptic morphotectonic histories. Despite their value, thermochronology studies within Zimbabwe are considerably lacking, especially within the cratonic interior. In this work, a multiple low-temperature thermochronology approach— including the first apatite and zircon (U-Th)/He data and a more spatially extensive apatite fission track dataset—is employed together with inverse thermal history modelling to unravel the Phanerozoic histories of the different tectonic provinces of Zimbabwe. The data reveal that structural reactivation, largely caused by stress transmission and associated with uplift and denudation of different crustal blocks, has played a major role in the morphotectonic evolution of Zimbabwe, albeit spatially and temporally variable. The new dataset allows for a more clearly defined spatial and temporal structural reactivation pattern and suggests that the cratonic interior experienced reactivation in the Paleozoic but has since remained tectonically stable. Cratonic Zimbabwe preserves a Pan-African signature associated with Gondwana amalgamation, whereas the eastern cratonic margin and neighbouring mobile belts are dominated by Jurassic Gondwana breakup signals. The spatial extent and trend of the Pan-African rejuvenation signature suggest that the anomalous topography of Zimbabwe may have an ancient component. The regional dataset suggests unroofing of a previously more extensive sedimentary cover over the craton that began in the Paleogene. The zircon (U-Th)/He dataset in this work provides significant methodological insight. The unexpectedly recurrent ‘inversion’ of low-temperature thermochronology ages suggests that moderately-extremely radiation-damaged zircons can, in certain geological settings, act as ultra-low-temperature thermochronometers and provide insight into the more recent morphotectonic history. However, at present, the current zircon α-radiation damage accumulation and annealing model (ZRDAAM) does not adequately capture the He diffusion behaviour of the majority of the dated zircons. The exact source of this issue in the zircon (U-Th)/He system is uncertain, but could be associated with a ZRDAAM calibration issue, an unaccounted source of error and/or a currently unrecognised factor affecting He diffusion and retentivity within zircon.