As a part of searching for economic deposits of sediment-hosted copper (SHC) mineralisation that might have formed within rocks of the Adelaide Rift Complex Neoproterozoic sedimentation sequence occupying an area located due east of Lyndhurst in the central northern Flinders Ranges, the project proponent First Quantum Minerals (FQM) sought to acquire first-pass high quality regional surface geochemical data there to assist in exploration targeting. Previously, such broadly focussed data had not been obtained by earlier explorers due to numerous logistical and technical obstacles pertaining to performing historic ground-based work in this area. But FQM intended to overcome these well described impediments by implementing a dedicated and well-coordinated program with clear aims, access to large prospective areas, strong logistical support, and appropriate funding. To help it achieve the second requirement, the company arranged exploration access agreements covering four tenements lying adjacent to its 100% held ELs 5899/5900 parcel, which are owned by Leigh Creek Copper Resources and R&J Resources, namely, ELs 6080, 6273, 6433 and 6577. In undertaking this research project, FQM believed that there would be hitherto untried promise for it to realise both immediate exploration targeting utility plus longer-term learnings for the industry, if it was to apply high quality multi-element geochemistry and spectroscopy (ASD – analytical spectral device) over an area of the Adelaide Rift that was identified as highly prospective for large SHC mineral systems. The work program was phased, with the methodology, sample spacing, and final coverage of regional geochemistry (Part B) determined by the effectiveness of the methods trialled in the orientation study (Part A) as well as budgets, and level of co-funding. The principal aim of the survey was to geochemically detect proxies of the larger-scale SHC mineral system beyond the Cu anomaly footprint. The detection of a copper deposit based on just copper as a pathfinder requires that the deposit must be exposed exactly at the present-day erosional level, while useful samples need to be densely spaced (at ~ 50 m to 200 m) in order not to ‘miss’ the copper deposit. Typically for SHC systems, the higher grade the deposit, the smaller the copper footprint. Most other important pathfinder elements dispersed within these SHC systems operate at a much larger scale and should in theory be detectable at a sample spacing of 500 m to 1000 m. This may also open the door to discovering deposits not perfectly exposed at surface, or having a very weak surface expression due to strong weathering or acid leaching from oxidising sulphides. The collection of a regional geochemical dataset with many data points over a large area ensures that background is well established, and provides a more consistent context. The mineral system elements of particular interest are zones of regional copper depletion, regional alteration, and regional to local metal precipitation on or below reductants. A total of 4205 surface sedimentary material samples were collected during the winter months of 2021 by a team of up to six technicians and two geologists, working on foot for the orientation phase sampling and moving to employ small, lightweight quad bikes for optimising time taken to conduct the main regional sampling phase. Part A, the geochemical orientation study, involved the collection of rock, soil and stream sediment samples along traverses over four copper-mineralised prospects to determine how the alteration and mineralisation signatures of the SHC system evolved from rock outcrop to residual soil to transported stream sediments in these particular environments, and which methods delivered the most effective footprints for regional detection. By looking at the different sub-samples and spacing, the company was then able to confirm that studying the geochemistry of regional soils form the most cost-effective approach needed to identify constituents of a SHC mineral system. Part B consisted of systematically collecting soil samples tenement-wide at 500 m to 1 km regular grid spacings, over an area covering approximately 1200 square km. Sample collection was completed by field technicians from Euro Exploration Services, under FQM supervision, to minimise collection time. The priority tenements were FQM’s ELs 5899 and 5900; the degree of further expansion of the survey into the adjacent ELs 6577, 6273, 6080 and 6433 was conditional on the timing of agreed access to those tenements. If access to them tenements had been revoked due to unforeseen circumstances, it was intended that working on ELs 6431 and 6432 in the Witchelina district could provide a viable alternative study area. Having this option proved to be unnecessary. The 1 km spaced soil samples were analysed both spectrally (ASD) and geochemically (laboratory high quality multi-element assay suite and pXRF), and the data obtained for 48 elements of interest were later integrated spatially with mineral system signatures discerned in existing other regional datasets including ASTER, radiometric, and airborne electromagnetic data. The 500 m spaced soil samples were collected over salt diapirs and in high priority areas such as those with shale bedrock subcrop, and were analysed spectrally (ASD) and geochemically (pXRF) for a limited range of 28 elements. Areas that stood out from a targeting perspective were later laboratory re-analysed for the full multi-element assay suite. The results of this work indicated that a combination of pXRF and ASD are able to map most mineral system elements, while potentially being a cheaper alternative to laboratory multi-element data. This procedure will not replace laboratory data, but merely narrows down where to focus a full multi-element analysis. Such an initial cost saving potentially also provides explorers with the opportunity to afford additional add-ons such as rare earths, gold, PGE’s or ultra-low detection limits if applicable to the target concept. These may reveal aspects of the mineral system that were previously unknown. The geochemical results so obtained were subsequently analysed with machine learning algorithms by FQM for generating many data element relational visualisation plots, to determine if such means could provide more success in differentiating concealed bedrock stratigraphic units and with identifying potential mineral system vectors, compared to following a more classic litho-geochemical approach like that exemplified in the published work of Zambian Copperbelt explorers. The machine learning approach was also used by FQM to notionally re-attribute the identities of mainly concealed strata, and thereby identify areas having possibly inconsistent past mapping. The results of the regional survey allowed for the identification of a number of elements of the mineral system, such as rock alteration caused by the passage of saline fluids, zones of copper depletion and enrichment, as well as distal dispersive pathfinder metal zonation. FQM now recognises that several reasonable copper and other base metal anomalies have been revealed by this survey which will require follow-up, especially those that are part of the mineral system, are not associated with historical workings, and are those associated with current targets. The follow-up may include on-ground anomaly validation, geological mapping and infill soil geochemical sampling. Any anomalies which are repeatable when infill sampled, have a coherent spatial extent and hence may represent a sizable target, will lead to drill testing, with the potential to transform geochemical indications into a discovery. FQM hopes that the datasets produced during this project can be utilised by other explorers as training data and to illustrate a viable workflow, as well as acting as a reference on how the regolith behaves in the remote desert of South Australia.