Understanding how gold forms is crucial for knowing where to find it and how to extract it sustainably.
Understanding how gold forms is crucial for knowing where to find it and how to extract it sustainably. McGill researchers have answered a long-standing question in geology that could lead to new ore discoveries.
Researchers traveled to the remote Brucejack gold deposit in northwestern British Columbia to study and collect ancient ore-bearing rocks. The deposit, now on land due to plate tectonic processes, originally formed in a submarine oceanic island arc about 183 million years ago. After analyzing the samples at McGill and the University of Alberta, they found seawater had mixed with ore fluids in the Earth's crust to form gold.
“These rocks, dating back to the Early Jurassic period, are hosted in volcanic and sedimentary formations,” said co-author Anthony Williams-Jones, Logan Professor of Geology and Geochemistry in McGill’s Department of Earth and Planetary Sciences. “Using high-resolution mass spectrometry, we decoded their unique chemical signatures. The finding of seawater-triggered gold deposition is novel and surprising.”
Read more at: McGill University
McGill Postdoctoral Research Fellow Duncan McLeish in his field area at the Brucejack Mine in August, 2022. (Photo Credit: Kevin Ng)
