Thirteen contiguous exploration licences located along the western margin of the Tertiary Murray Basin were taken up by CRA to search for economic buried brown coal / lignite deposits of the type already known from small discoveries that had been made earlier by other parties at Sedan, Anna and Moorlands. In the second year of tenure, the company's search objectives were widened to include possible buried occurrences of diamonds, base metals and gold. Initially, an assessment was made of available past drillhole and geophysical survey data to define coal-prospective areas, before CRA began acquiring >24,000 line km of new airborne magnetic and radiometric surveys to provide structural and lithological information about the pre-Tertiary basement. Detailed ground gravity surveys were conducted in 1980 and 1981 to map basement topography and evaluate the contribution of fault structural controls towards initiating and maintaining local environments suitable for lignite deposition. Follow-up exploratory drilling entailed completing 104 vertical rotary mud holes for a total penetration of 16,270 m, including coring a total of 57 m as tails to three holes, and subsequently performing geochemical analyses of >1400 drill samples. 75 of the holes for 12,694 m were drilled to explore for lignite, while the remainder targeted inferred kimberlite and metallic mineral prospects. Drilling for coal along the downthrown [eastern] side of the Morgan Fault intersected thin (<2 m) lignite beds within the Eocene Renmark Beds in 10 holes, including a 7 m thick lignite seam from 195 m depth in RD84WA1. However, based on its drilling results obtained in 19 holes that recorded coal horizons, it appeared to CRA that significant lignite is unlikely to be found within the favoured upper Renmark Beds facies in the subject tenements region at <120 m depth, downgradind the chance of finding a mineable coal resource. A poorly outlined potential deposit of 580 Mt of kerogen-rich lignite was estimated to exist in the Quondong Vale - Peake area, based mainly on coal analysis data obtained from a 4.4 m thick lignite seam intersected in hole 81MBR36, as confirmed from later cored intercepts, with a shale oil yield of 108.7 l/t reported from retorting of sapropelic coal containing up to 89.4% kerogen. After the reading of ground magnetic surveys to delineate 107 selected anomalies that were interpreted as arising from buried intrusive igneous plugs, exploratory drilling which was done at 24 of these chosen as being characterised by potentially kimberlitic, short strike length aeromagnetic responses encountered a variety of magnetic basement rocks. They included two kimberlitic basalt breccias disclosed at depths of 114 m and 214 m in holes 82FS3RM1 and 83FS66RM1 / RD84WA1 that are sited respectively 8 and 10 km north-northwest of Blanchetown. Chrome diopside, chromite, picroilmenite and pyrope garnet grains were observed in heavy mineral samples recovered by panning bottomhole drill cuttings from both holes. However, following a consultant's optical mineralogical investigation of the breccia samples, their potential to contain diamonds was considered to be low. The conduct of an EM-37 ground geophysical survey plus two Sirotem surveys and a CSAMT survey over the shallower breccia flow which was hit at anomaly FS3 all produced results which failed to delineate that body. Anomalous concentrations of copper, gold and manganese were returned from assayed drill cuttings samples of interlayered andesitic volcanic rocks and chlorite - magnetite schist encountered in hole 82FN3RM1, located north of Kia Ora Homestead. Three traverses of ground EM surveying were run across this prospect, but did not reveal any conductors. Vertical rotary percussion drilling of one of 5 discrete and intense aeromagnetic anomalies recognised in the Florieton area encountered a magnetic gabbro in hole 82MP1, but no significant base metal mineralisation was recorded. Planned further work to investigate the other anomalies was cancelled by CRA due to the likely excessive thickness there of Tertiary cover.