Two researchers from Queensland University of Technology (QUT), Carl Walsh and Professor Balz Kamber, utilized a laptop and a rock from a diamond mine’s waste pile to address a long-standing geological puzzle regarding diamond formation in ancient continents. Their study, published in Nature, reveals that diamonds’ rarity is due to their specific geological origins rather than erosion over time, prompting a reevaluation of diamond exploration strategies. Walsh’s research involved computer modeling of a garnet harzburgite sample, 3.3 billion years old, from a kimberlite pipe in South Africa’s Kimberley mine. This modeling explored how the material from deep mantle roots forms under varying temperatures, allowing the scientists to compare predictions with actual mineral compositions. They challenged the prevailing view that ancient continental roots were once rich in diamonds that have since been lost to erosion. Instead, their findings suggest diamonds have always been rare, offering insights into the mantle processes that create them. The research highlights the significance of ancient mantle plumes in distribution of heat and temperature within the Earth, influencing the conditions under which diamonds form. Walsh has since continued to investigate similar rocks at the Australian National University, furthering understanding of diamond origins.
