Three study areas were chosen to investigate a number of stratigraphic horizons, the Waterhouse Range, Glen Helen and Ross River areas. constraining magnetisation direction using geological data. In this study, we investigate the relationships between dip and magnetisation using an approach that would generally be considered a little backward, i.e. Normally it would be optimal to measure the magnetisation, but this is not always possible or feasible. However, because of the mathematical trade-off between the dip and magnetisation of bodies, the dips of the bodies cannot be known unless the magnetisation is also known. Magnetic modelling techniques can be utilised on these stratiform anomalies to extrapolate the near-surface structure of the basin. The Amadeus Basin displays subtle magnetic anomalies that trace strata for considerable distance, highlighting complex folding patterns. However, the mechanism of evaporation-driven fractionation of δ¹☼ is different from the commonly proposed inorganic-organic carbon fractionation, and challenges the views on interpreting global chemostratigraphic anomalies or excursion and their cause. The Bitter Springs Group chemostratigraphy has been correlated globally and the negative excursion was named previously after this unit (Bitter Springs Stage anomaly). The salinity and high evaporation is reflected in positive δ¹☼ in carbonates (+4 to +6 ‰ VPDB) of the evaporitic units, while the shallow marine incursion of the Loves Creek Formation (-2 ‰ δ¹☼) show typical marine carbonate isotopic values. The overall regression was interrupted by a transgressive phase lasting at least 20 Ma and leading to deposition of basin-wide stromatolitic dolostone (Loves Creek Formation). The deposition of halite occurred in shallow marine, lagoon (salina) environment (Gillen Formation), and developed into sulphate-dominated supratidal sabkha during sea level regression (Johnnys Creek Formation). The Tonian Bitter Springs Group (∼830-750 Ma), within the Amadeus Basin in central Australia consists of thick halite and sulphate evaporite accumulations.
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