4. Game Changers – Olympic Dam and IOCG Deposit Models, Geometallurgy and Big Data

The discovery of Olympic Dam in Australia captured the imaginations of exploration geologists around the world – over 40 years later we are just beginning to appreciate the nature and extent of what a ‘game changer’ Olympic Dam was for the mining industry. In this episode we talk to one of the most knowledgeable geoscientists about the deposit, Kathy Ehrig (BHP) about its discovery, mineralogy, structural control and massive size. That is all captivating in itself, but the discovery also prompted recognition of an entirely new class of ore deposits, Iron-Oxide-Copper-Gold, or IOCG and research around the world into the processes which may be at work to produce these enigmatic deposits. Tim Baker (Eldorado Gold), with extensive experience in IOCG deposit research, takes us through the various models.The sheer complexity of Olympic Dam also created significant metallurgical problems. Kathy Ehrig led the team that developed new approaches and data analysis to identify the problems, effectively doing ‘geometallurgy’ before the term was widely applied, and setting standards for others to follow. Betsy Friedlander (Teck Resources), an exploration geologist now working on geometallurgy at the Trail Facility in British Columbia, sheds light on the how important the whole area of geometallurgy has become and why we should be thinking about it from the earliest stages of exploration.So you might have guessed already, but where does this lead us back to? Big data, and Kathy comes full circle in this episode, helping to place the role of big data into the whole complex picture of a giant among ore deposits.The Ore Deposits Hub is sponsored by SEG-SGA-IAGODoredepositshub.comFor more insights and stories with Kathy Ehrig, listen to Exploration Radio episode #34 sponsored by SEGexplorationradio.comTheme music is Confluence by Eastwindseastwindsmusic.comCome join us in Salt Lake City, Utah for SEG 2026, September 30th to October 3rd. You can expect world-class technical content, including iconic ore deposits and the geological processes of North American Cordillera. The program balances applied case studies, framework geology, and technological innovation. The conference offers a unique opportunity to connect, learn, and help shape the future of economic geology. See you there.