An area surrounding the historically worked Ediacara lead-zinc Mineral Field, overlying the inferred far eastern margin of the Gawler Craton, was explored for possible economic hydrothermal/stratabound base metals within the Adelaidean and Cambrian cover rocks, and for IOCG style copper-gold mineralisation within the underlying older ?Mesoproterozoic basement. Because the existing regional gravity data coverage for the licence area was sparse over its central and southern sections, Minotaur Exporation chose initially to undertake a new gravity survey covering the entire tenement, with readings acquired at a 1 km x 1 km spacing in general, infilled to 500 m x 500 m apart across the licence's southern part. 1129 stations were read during October and November 2007, including some closely spaced stations laid out along two east-west traverses that cross the northern and southern ends of the Ediacara Range. The new gravity data clearly defined a 30 km long, curvilinear positive anomaly which has an amplitude of 7-8 mGal. However, a very strong correlation between the gravity data and topography was apparent, as illustrated by overlaying it on the satellite digital elevation image for the region between Mount James and Nilpena Homestead. The arcuate nature of the residual positive gravity anomaly was interpreted as a high-angle reverse thrust (dipping eastwards) formed during the Cambrian-Ordovician Delamerian Orogeny, probably from re-activation of a pre-existing Neoproterozoic extensional fault that originally controlled the distribution of sediments and facies within the margin of the Adelaide Geosyncline. This thrust was optimistically regarded as responsible for (i) uplifting dense lithologies to a higher structural level and (ii) focussing fluids. At this stage it was understood that no past drillhole information existed with which to check the subsurface geology associated with the gravity anomaly. Consequently, two-dimensional block modelling of the gravity data obtained along profile 6594000mN was performed in order to ascertain the various possible depths, orientations and the geological nature of the physical body causing the regional positive gravity high. This exercise yielded several differing but plausible geophysical scenarios for causative bodies, but the best fits between observed and computed gravity data profiles came from the shallower block models, especially for their western portions. The most favoured interpretation was that some dense (~3.0 g/cc), largely non-magnetic lithologies are likely to occur there at depths of only 100-200 m below ground level, as an easterly dipping series of blocks and/or surfaces. Before Minotaur had committed itself to drilling a test hole on the Mount James structure, the company's ongoing reviews of available past exploration data disclosed that there actually was a pre-existing drillhole which had penetrated into the gravity feature. This particular drillhole had encountered a thick sequence of Adelaidean strata, thereby indicating that the gravity feature was probably entirely due to a shallow, thick wedge of Adelaidean rocks. This revelation overturned Minotaur's earlier interpretation that the gravity feature was due to a shallowing of Gawler Craton basement unit rocks beneath only a thin layer of Adelaidean rocks. Subsequent gravity modelling proved that the entire gravity response could be caused by the thick wedge of Adelaidean rocks. Minotaur decided that the gravity feature was no longer of interest to it, since there did not appear to be any shallow IOCG - prospective basement present there, and because the shallow Adelaidean sequence would not be sufficiently prospective to warrant further exploration activity. Attention then turned to assessing the economic potential of some known barite mineral occurrences within EL 3921, based on information available in PIRSA's GIS database. Approximately 20 occurrences lie in a curvilinear array coincident with the Mount James gravity anomaly. Metal zonation is apparent along the structure: a central Cu-Pb-Ag-(Ba) zone is surrounded by a Pb-Ag-(barite) zone and a peripheral barite-only zone. The barite occurrences had previously been interpreted to relate to a 'sedimentary exhalative' mineralisation model, i.e. a syn-sedimentary fault zone reactivated during the Delamerian Orogeny served as a fluid conduit, with a metal-rich zone occurring proximal to the fault whilst a barite halo extends further beyond the conduit. The halo of barite-only deposits recorded around the Ediacara Mineral Field predominantly occur as discordant veins of various strike orientations, however, NE-striking veins are the most commonly documented. It was decided not to conduct a field inspection of the barite occurrences on the licence area, as their size and commercial viability appeared to be limited.