"Ore" is rock that can be profitably mined for its metal content. Ores containing gold and platinum are well known to be valuable, but in fact all the metals in the periodic table have market value owing to their wide range of commercial, scientific and medical applications. Therefore, despite the contribution of recycling, vast tonnages of ores need to be mined each year to keep our industrialized societies rolling. It is one of the great tasks of geologists, and of the geological sciences in general, to find new ore deposits at a rate that meets the global demand.
A sobering truth is that most ore deposits that outcrop at the Earth's surface have already been discovered and exploited. The challenge for geologists of today and in the future is to find buried deposits – a far more difficult undertaking than traditional gold-rush-style prospecting. Modern exploration requires a high degree of scientific insight into how Nature has formed the ore deposits in the first place.
We are therefore carrying out research to understand the genesis of ore deposits, such that exploration companies may use the resulting genetic models to guide their field campaigns. We focus on the class of ore deposits in which hot, high pressure aqueous solutions (hydrothermal fluids) have transported metals in the dissolved state through the Earth's crust. Rock–water interaction along the flow paths has led to precipitation of the metals in locally high concentrations.
These valuable sources of copper and zinc form in zones of submarine extensional tectonics where magma rises to the seafloor, erupting huge quantities of pillow lavas.
Much of the gold that is mined around the world every year is extracted from quartz-pyrite-carbonate veins that sit within faults and shear zones in metamorphic belts. Ore-grade occurrences are termed "orogenic gold deposits" because they are typically found in tectonic collision zones marked by mountain belts (or their eroded remnants). The genesis of this important type of gold deposit is still poorly understood and this poses a hindrance to exploration. We are conducting research into how orogenic gold deposits form, based on field and laboratory studies, mostly using geochemical methods.