Primary Industries and Resources SA submitted 50 thin sections of cuttings to PGPC for brief petrological description. Samples were selected by the late Dr David Gravestock from the Cooper and Warburton Basins. Four samples from Tarragon-1 included chips of igneous origin and therefore have been described by Dr Doug Mason of Mason Geoscience Pty Ltd. The study was designed to further characterise the nature and distribution of an altered zone recognised at the top of the Warburton Basin and to discriminate between sediments of the Cooper and Warburton Basins.