| Summary: | Life on Earth during the Mesoproterozoic was challenging with an aggressive low oxygen atmosphere, acidic hydrosphere, intense weathering of the lithosphere, and simple bacteria-plankton biosphere. The research within the following thesis investigates the interaction between the atmosphere, hydrosphere, lithosphere, and biosphere through an assessment of provenance, sedimentology, and characterisation of mineral systems of the Pandurra Formation in southern Australia during the Mesoproterozoic. The Pandurra Formation preserves evidence of the gradual erosion of the Gawler Range Volcanics and subsequent climate variation of the region. This study characterises the mechanisms for sedimentation of the Pandurra Formation from the rapid lateral and vertical variation that resembles a multi-thread anabranching braided distributive fluvial system. This research identifies seven lithological associations that are not consistent with the existing four-member model. This investigation reveals that the Pandurra Formation commenced sedimentation soon after 1562 ± 32 Ma. The zircon geochronology of the Pandurra Formation is similar that of the underlying pre-Mesoproterozoic basement geology, and matches with the observed regional geology of the Archean (2560 to 2500 Ma) and late Palaeoproterozoic to early Mesoproterozoic (1900 to 1450 Ma) Gawler Craton. Sm-Nd isotopic geochemistry reveals that the source age of the Pandurra Formation sediments varied with time from Archean dominated to Palaeoproterozoic back to an Archean signature. This research indicates a connection with the Pandurra Formation to the coeval Belt-Purcell Supergroup in North America, but not to the Rocky Cape Group in Tasmania or the East Antarctic Shield during the Mesoproterozoic. The Pandurra Formation represents a series of elevated terrestrial distributive fluvial systems that supplied sediment to the deep water Pritchard Formation from 1470 to 1454 Ma. Evidence of two fluid flow events at 1211 ± 24 Ma (Vanguard-1) within the Pandurra Formation and at ...
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