A data review undertaken by MESA to assess the prospectivity of the northern Flinders Ranges intramontane basins for concealed Triassic coal, highlighted four main areas as having the best potential for a discovery. Of these, the alluvium-covered plains in the Leigh Creek/Lyndhurst area were considered the most prospective, and in early 1993 ETSA and MESA agreed to jointly explore the area for coal. Drilling targets were defined through a combination of re-interpretation of existing gravity data and, in areas close to Leigh Creek Coalfield, infill drilling at approximately 2 km spacings between previous exploration drillholes. Infill drilling was chosen to test the area for basins of a potentially economic size (minimum 2 km x 2 km) which may not show up in existing gravity survey information. A program of 112 reverse circulation drillholes totalling 4817m was completed within ELA 382/92, with two holes (CP1 and CP2) intersecting coal-bearing sediments of Triassic age in an area south of Copley. These holes identified the presence of a previously unknown coal basin which warranted further investigation (Shaw, 1996a (in prep.)). A total of 86 samples were submitted for bedrock assay, 32 for palynology, and 5 for petrographic/mineralogical examination. Some bedrock samples showed elevated zinc values, however, no analytical results warranted any follow-up work. Thirteen water samples were collected from drillholes, with samples from 4 holes identifying a supply of water within Tertiary sands south of Lyndhurst (salinities between 5,000 and 10,000 mg/L, and flow estimates between 0.7 and 1.0 L/s), which may have potential for future industrial use. Three water samples were submitted for full chemical analysis. Gravity lows tested which did not intersect coal bearing sediments were thought to be due to Quaternary-Tertiary sediments within bedrock depressions, deeply weathered bedrock or variations in bedrock lithology.