These rocks were long thought to have formed on the ancient seafloor in close proximity to ‘black smokers’ hydrothermal vents. On the modern seafloor, a rusty brown, metal-rich mud is commonly found around these hydrothermal vents, assumed to be an analogue of ancient BIF. This connection makes BIF a valuable indicator of ore-forming processes since similar ancient hydrothermal systems produced mineral deposits that are now preserved on land and mined for copper, zinc, lead, and gold.
David Diekrup, a recent PhD graduate in the Department of Earth and Environmental Sciences, examined thin sections of BIF under optical and electron microscopes to reconstruct and understand how the minerals in the rock formed. He related these observations to their chemical and isotopic composition and proved that these iron-rich rocks did not form close to hydrothermal vents after all. With guidance from his supervisor Professor Mark Hannington, David developed a model of BIF deposition in the open ocean, away from hydrothermal venting and suggested that these deposits were likely a result of early bacterial activity. Microbes are intimately associated with the biogeochemical cycling of metals. Their activity can result either in metal mobilization or immobilization depending on the mechanism involved and the microenvironment where the organisms are located. These findings have important implications for understanding the ancient oceans and development of BIF on earth.
David attributes his success to the Ottawa-Carleton Geoscience community and the support that he received from fellow students, professors, technicians, and administrators. Some of the most rewarding experiences during his time as a graduate student were involvement in extracurricular activities, including serving as co-president of the Society of Economic Geologists Student Chapter, which organizes student conferences and field trips.
Currently as a research associate with Prof. Hannington, David is the program coordinator of the NSERC-funded Collaborative Research and Training Experience program in Marine Geodynamics and Georesources (iMAGE), an initiative aiming to bring together Earth science students from across Canada and connecting them with prospective industry partners.
