Scale-integrated architecture of a world-class gold mineral system: The Archaean eastern Yilgarn Craton, Western Australia

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World-class mineral systems, such as those found in the Archaean eastern Yilgarn Craton, are the product of enormous energy and mass-flux systems driven by lithospheric-scale processes. These processes can create big footprints or signatures in the lithosphere, which can be observed at a range of scales and via a variety of methods: including geophysics, isotopes, tectonostratigraphy and geochemistry. We use these datasets to describe both the architecture (structure) of world-class gold systems of the Yilgarn Craton and the signatures of their formation. By applying an understanding of the most critical elements of the process, and their signatures, new areas, especially undercover, may be targeted more predictably than before. Knowledge of the major architectural elements of the Yilgarn Craton has increased greatly over the last decade, through the collection of a wide range of geophysical, geochemical and isotopic data. These data range in scale from (1) lithospheric-scale, which provide information on the entire craton and their underlying volumes down to depths in excess of 350 km, through; (2) regional-scale, which provide information at the province scale and to depths of 30–40 km, to; (3) mine- and camp-scale, which provide information on the top few kilometres of the crust. The architecture (structure) in the upper mantle and lower crust can be inferred from broadband seismic tomography and analysis of long-wavelength gravity data. Geophysical data, such as magnetotellurics and deep-crustal reflection seismic, also provide evidence for the signatures of the flow of fluids through this architecture (the pathways) and they illustrate that the scale of the system is many orders of magnitude larger than the immediate deposit itself. Of particular importance is the role of deep-crustal-penetrating shear zones or faults which link the mantle with domes in the upper crust. Together, these data provide first-order insights into the physical and chemical properties of the Yilgarn Craton. These insights provide geodynamic clues and constraints as to why the Yilgarn is so well endowed in metals such as gold ( Groves et al., 1989). The intersection of favourable architectural features provides connections between the mantle and the upper crust in the Kalgoorlie region, possibly explaining why this area is so well endowed in comparison to others.