The area of the Tiparra-Moonta Military sheet (scale ½ mile to the inch) has been mapped by the writer during 1954-55. Aerial photographs on the same scale have been used as a topographic base for the plotting of the geological data in the field. Unlike many other mapping terrains in which outcrops provide a reasonable basis for the identification of the rock formation and their structural features, the area surveyed is a plain mantled by Recent-Pleistocene deposits which conceal the rock formation. For this reason the numerous excavations (dams, underground tanks, road metal quarries, prospecting pits, shafts and so on) were the chief sources of geological information. The primary purpose of the present survey was to establish criteria for the geological classification of the area with special reference to the search for copper. From this view point the soil and subsoil were formations of special interest. A series of maps covering the subject has been compiled.