This report deals with the stratigraphy and economic geology of an area on the eastern margin of the Eucla Basin and the western margin of the Gawler Block. The area is centred upon the FOWLER 1:250 000 map area. The stratigraphic section of the report, which provides a framework for the more detailed geological investigations connected with the search for economic mineral deposits, deals with Precambrian basement rocks, basin sediments and surficial deposits mainly of Cainozoic age. The oldest rocks in the area are gneisses and schists which are tentatively correlated with the Cleve Metamorphics. Recent age dating suggests that younger granites were probably emplaced a little more than 1500 m.y. ago, that is, at the time of the Wartakan Phase of folding and acid volcanism which ended the Carpentarian orogenic cycle in the Gawler Block. Basin sediments of Palaeozoic and Mesozoic age occur in adjoining basins. The portion of the Eucla Basin lying within the map area contains up to 60 m thickness of Cainozoic sediments overlying basement rocks. Cainozoic Pidinga Formation and Nullarbor Limestone crop out, and surficial deposits blanket the area. Exploration for mineral deposits is recorded as long ago as 1885. Base metals, lignite, alunite, uranium, oil in adjoining basins, and brines have all been sought since that time. Current exploration is for uranium and thorium, which it is thought may be associated with lignites within the Pidinga Formation. Despite much geological exploration, radiometric work and drilling, the source of the area's high radioactivity remains unknown, and no economically important deposits of uranium have been discovered.