Controls on fluid flow and metal deposition in sediment-hosted hydrothermal ore deposits

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Sediment-hosted hydrothermal ore deposits represent globally significant sources for many metals including copper, cobalt, lead, zinc, uranium, arsenic and germanium. Sediment-hosted deposits are difficult to discover because they have "cryptic" mineral alteration (i.e. alteration invisible to the eye). In addition, processes responsible for forming high-grade ore deposits are uncertain. This means that new geochemical tools are required that will enable recognition and mapping of the key processes and alteration footprints for these deposits. During the flow of hydrothermal fluid through rock, a series of reaction fronts will be established. These reaction fronts will manifest as changes in ore metal abundances, mineralogical alteration, stable isotope ratios and temperature. Accurate mapping of temperature variations is difficult, with index alteration minerals (e.g. illite, biotite) providing insufficient temperature precision, and fluid inclusions often not well preserved in sediment-hosted hydrothermal deposits. This research program will develop new methods for providing precise temperature measurements from carbonate minerals formed at up to 350 oC  utilizing clumped carbon and oxygen isotopes. The program will develop new methods and datasets for quantifying alteration mineralogy and variations in primary and secondary textures across scales (from the thin section to deposit scale) within sediment-hosted ore deposits in order to create new ore deposit models. Finally, we will seek to test and develop new exploration tools for sediment-hosted copper deposits focussing on recognizing unique textures and chemistry of resistate indicator minerals such as apatite, rutile and monazite. Collectively, this research program will both develop fundamental new knowledge on the genesis and alteration of sediment-hosted ore deposits, develop new exploration tools and methods suitable for discovering new deposits, and train the highly qualified personnel who will be needed to deliver the mineral resources required for the low-carbon energy transition.