Despite having been a target for volcanic-hosted massive sulfide (VHMS) deposits since the 1960s, few resources have been defined in the Archean Yilgarn Craton of Western Australia. Exploration challenges associated with regolith and deep cover exacerbate the already difficult task of exploring for small, deformed deposits in stratigraphically complex, metamorphosed volcanic terranes. We present results of drillcore logging, petrography, whole rock geochemistry and pXRF data from the King Zn deposit, to help refine mineralogical and geochemical halos associated with VHMS mineralization in amphibolite facies greenstone sequences of the Yilgarn Craton. The King Zn deposit (2.15 Mt at 3.47% Zn) occurs as a 2-5m thick stratiform lens dominated by iron sulfides, in an overturned, metamorphosed volcanic rock-dominated sequence located ~140km east of Kalgoorlie. The local stratigraphy is characterized by garnet amphibolite and strongly banded intermediate to felsic schists, with rare horizons of graphitic schist. Massive sulfide mineralization is characterized by stratiform pyrite-pyrrhotitesphalerite at the contact between quartz-muscovite schists ('the footwall dacite') and banded quartz-biotite/amphibole±garnet schists of the stratigraphic hanging-wall. A zone of pyrite-(sphalerite) and pyrrhotite-pyrite-(chalcopyrite) veining extends throughout the stratigraphic footwall. Footwall garnet-amphibolites are of sub-alkaline basaltic affinity, with a central zone dominated by chlorite±magnetite interpreted to represent the Cu-bearing feeder zone. SiO2, CaO, Fe2O3T, MgO and Cu concentrations are highly variable, reflecting quartz-epidote±chlorite±magnetite±sulfide alteration. Hydrothermal alteration in stratigraphically overlying intermediate to felsic rocks is characterized by a mineral assemblage of quartz-muscovite±chlorite±albite±carbonate. Cordierite and anthophyllite are locally significant and indicative of zones of Mg-metasomatism prior to metamorphism. Increases of SiO2, Fe2O3T, pathfinder elements (e.g. As, Sb, Tl), and depletions of Na2O, CaO, Sr, and MgO occur in footwall quartz-muscovite schists approaching massive sulfide mineralization. Within all strata (including the immediate hanging-wall), the following pathfinder

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the source for the world-class placer gold deposits made famous in the Klondike Gold Rush. However, the recent discovery of gold within a unit of felsic schist led to a new model for mineralisation that included an understanding of host rock rheology and composition. The mapping project aimed to provide a refined structural framework and subdivide the complex schist units that were previously classified as 'undifferentiated'.The increasing capability of portable mapping devices has led to paperless mapping and workflows that allow capture, integration and interpretation of data in the field. SRK ES used ESRI's ArcGIS mapping and analytic software to share base maps, collect data, and generate map interpretations. The workflow involved ArcOnline ™ and Collector ™ to collect data which was then inspected by teams based on site and in the head office.The integrated approach to lithological and structural mapping worked efficiently and effectively for the Klondike Gold District. Additional technologies are being actively developed at SRK ES to improve the efficiency of planning and completing field mapping. The increasing application of machine learning is also providing opportunities to generate preliminary map-based prospectivity interpretations from remote sensing and geological data.The fundamental skills involved in lithological and structural mapping remain broadly the same, but technological advancements and improvements to data quality make the process much more effective and efficient.