- © 2007 Society of Economic Geologists, Inc.
The Gawler craton in South Australia hosts the Olympic Dam Cu-U-Au deposit, the world’s preeminent iron oxide copper-gold (IOCG) deposit and largest uranium resource. With a total resource now standing at 7.7 billion tonnes, Olympic Dam is also one of the world’s largest copper and gold deposits (BHP Billiton, 2007 Annual Report).
The emergence of IOCG deposits as a recognized mineral deposit class (Hitzman et al., 1992) has been followed by increasing interest in these deposits from explorers and researchers. IOCG deposits are attractive exploration targets because of their favorable grade-tonnage characteristics, credits of gold and other metals (e.g., U, Ag), and physical characteristics that are particularly amenable to geophysical exploration techniques. Despite this growing interest and an increasing number of published descriptions of the major deposits, there have been few multidisciplinary integrated studies of the regional geologic settings and metallogeny of major IOCG provinces globally.
As one of the world’s key IOCG provinces, the Gawler craton has experienced rapid growth in exploration expenditure this decade, resulting in discoveries of the Prominent Hill IOCG deposit in 2001 and the Carrapateena deposit in 2005 (Fig. 1⇓). Over the period of these discoveries in the eastern Gawler craton, explorers in the central Gawler craton were defining a number of new gold prospects. Earlier this decade, detailed descriptive data for this mineralization were not available, and the metallogenic setting of the gold-dominated, as well as IOCG, mineral systems was poorly understood. This partly reflected the early stage of exploration and also the difficulties in undertaking geologic and metallogenic …