This paper examines fault complexity in epithermal environments with an attempt at simplification that may lead to improved incorporation of structural techniques in exploration for this deposit style. Thanks in part to major mining, exploration and research in the Yilgarn and Abitibi gold provinces (and elsewhere), structural controls on mineralization in mesothermal environments are moderately well understood. The architecture and kinematics of fault arrays can be used, relatively successfully, for analysing mineralised fault potential, including the more recent use of sophisticated analogies involving active earthquake dynamics (Mickelthwaite & Cox, 2004). By gathering data on features such as fault bends, branches, related tension- and shear-veins, and breccia geometries, two- and three-dimensional models can be built. These constructions are usually intended to be predictive for explorationists, in the sense that the incremental strain field that can be inferred from meso-scale structures can be applied elsewhere at meso- to macro-scales, on the same or similar structures, and these may ultimately relate to paleo-plate movement vectors, or at least recognisable compartmentalisation of broad scale displacement vectors (Fig. 1a). In the epithermal mineralization environment, structural controls may be more complex. In some locations, the behaviour appears to be systematic (Fig. 1a, c), but in others, the degree of complexity can be high, such that individual kinematic determinations at local scales may have little apparent relationship to the far-field stress conditions that reflect the tectonic environment (Fig. 1b, d).
CITATION: Oliver, N H S, Rowland, J, McLellan, J G and Holcombe, R J, 2019. The (dis)organisation of structural controls on epithermal mineralization, in Proceedings PACRIM 2019, pp 3639 (The Australasian Institute of Mining and Metallurgy: Melbourne).