A solid geology interpretation of the Tallaringa and Ooldea magnetic surveys

Abstract

The Gawler Province in South Australia, is a Mesoarchaean to early Mesoproterozoic crystalline basement block underlying nearly half of South Australia. However, large portions do not outcrop, particularly in the west, where specific basement information below Phanerozoic cover is derived mainly from drill hole material. In such environments, geophysical data is of paramount importance in understanding basement geology for the purposes of mineral exploration. Two magnetic surveys in the Tallaringa-Ooldea area of the western Gawler Province were flown for Primary Industries and Resources South Australia (PIRSA) and Geoscience Australia (GA) during 2005-2006. A solid geology and structural interpretation of the areas was undertaken, incorporating the new data with existing data and additional geological and geophysical datasets. This new interpretation illustrates an underlying geology comprising Proterozoic and Archaean lithologies, consistent with the regional setting. Areas of interest in this area include parts of the Tallaringa Trough, the southernmost extent of the Nawa Ridge, and the One Tree Anomaly.