The mineralogical and lithogeochemical footprint of the George Fisher Zn-Pb-Ag massive sulphide deposit in the Proterozoic Urquhart Shale Formation, Queensland, Australia

The Proterozoic Carpentaria Province (McArthur basin and Mount Isa Inlier) in northern Australia comprises a number of world class clastic dominated (CD-type) Zn-Pb massive sulphide deposits, formally known as SEDEX deposits. In order to identify the geochemical footprint any mineralizing system it is necessary characterize compositional variability host rock mineralization. southern Carpentaria, establishing baseline composition complicated by varying degrees tectonic overprint, lack metamorphic indicator minerals, overall size ore forming systems. this study, samples from drill-holes intersecting main bodies at George Fisher CD-type deposit have been compared drill-hole barren, correlative lithologies Urquhart Shale Formation (ca. 1654 Ma). Bulk lithogeochemical (X-ray fluorescence, inductively coupled plasma mass spectrometry LECO) mineralogical diffraction) analyses combined with petrographic observations (1) establish (2) determine Fisher. absence preservation illite un-mineralized Shale, suggests that part area, rocks did not reach greenschist facies conditions (>300 °C). Chlorite very fine grained (≤ 10 μm) within interstitial pore spaces other phyllosilicates (e.g., illite), interpreted be diagenetic origin. Relative first stage mineralization (Zn-dominated, stratabound) associated decreased abundances albite, chlorite, calcite, higher dolomite (muscovite phlogopite). These transformations are strong minor trace element depletion (Sr Na) enrichment (Tl Mn). An index based on suite elements (GF = 10400Tl+Mn10Sr+Na) highly effective differentiating between background alteration may provide an additional tool for exploration programmes area. This study affirms benefit combining lithogeochemical, mineralogical, data understand